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When VAD Things Happen to Good People [Editorial]

2017-08-27T23:24:12-07:00

In his book, When Bad Things Happen to Good People, Harold Kushner explores explanations for human pain and suffering. He notes that while many of the afflictions of the human condition are beyond our understanding, none of us are exempt from the common experience. Despite the original publication of this thesis more than 35 years ago, Kushner's musings draw parallels to the patient experience with mechanically assisted circulation. The underlying mechanism and management of several morbid and mortal left ventricular assist device (LVAD) complications are beyond contemporary understanding but are sufficiently frequent to be considered common. The paper by Soliman in this issue of Circulation adds clarity to the question about why VAD things happen to good people by defining pre-operative risk factors that predispose patients to the development of right heart failure following implantation of a left-sided mechanical blood pump.



Genetic Predisposition, Clinical Risk Factor Burden, and Lifetime Risk of Atrial Fibrillation [Original Research Article]

2017-11-12T14:50:23-08:00

Background—The long-term probability of developing atrial fibrillation (AF) considering genetic predisposition and clinical risk factor burden is unknown.Methods—We estimated lifetime risk of AF in individuals from the community-based Framingham Heart Study. Polygenic risk for AF was derived using a score of approximately 1,000 AF-associated single nucleotide polymorphisms. Clinical risk factor burden was calculated for each individual using a validated risk score for incident AF comprised of height, weight, systolic and diastolic blood pressure, current smoking status, antihypertensive medication use, diabetes, history of myocardial infarction, and history of heart failure. We estimated the lifetime risk of AF within tertiles of polygenic and clinical risk.Results—Among 4,606 participants without AF at age 55 years, 580 developed incident AF (median follow-up, 9.4 years; 25th-75th percentile, 4.4-14.3 years). The lifetime risk of AF after age 55 years was 37.1%, and was substantially influenced by both polygenic and clinical risk factor burden. Among individuals free of AF at age 55 years, those in low polygenic and clinical risk tertiles had a lifetime risk of AF of 22.3% (95% confidence interval [CI], 15.4%-29.1%), whereas those in high risk tertiles had a risk of 48.2% (95% CI, 41.3%-55.1%). A lower clinical risk factor burden was associated with later AF onset after adjusting for genetic predisposition (P value <0.001).Conclusions—In our community-based cohort, the lifetime risk of AF was 37%. Estimation of polygenic AF risk is feasible, and together with clinical risk factor burden explains a substantial gradient in long-term AF risk.












Availability and Use of Shared Data From Cardiometabolic Clinical Trials [Original Research Article]

2017-11-13T14:50:21-08:00

BACKGROUND: Sharing of patient-level clinical trial data has been widely endorsed. Little is known about how extensively these data have been used for cardiometabolic diseases. We sought to evaluate the availability and use of shared data from cardiometabolic clinical trials.METHODS: We extracted data from ClinicalStudyDataRequest.com, a large, multisponsor data-sharing platform hosting individual patient-level data from completed studies sponsored by 13 pharmaceutical companies.RESULTS: From January 2013 to May 2017, the platform had data from 3374 clinical trials, of which 537 (16%) evaluated cardiometabolic therapeutics (phase 1, 36%; phase 2, 17%; phase 2/3, 1%; phase 3, 42%; phase 4, 4%). They covered 74 therapies and 398 925 patients. Diabetes mellitus (60%) and hypertension (15%) were the most common study topics. Median time from study completion to data availability was 79 months. As of May 2017, ClinicalStudyDataRequest.com had received 318 submitted proposals, of which 163 had signed data-sharing agreements. Thirty of these proposals were related to cardiometabolic therapies and requested data from 79 unique studies (15% of all trials, 29% of phase 3/4 trials). Most (96%) data requesters of cardiometabolic clinical trial data were from academic centers in North America and Western Europe, and half the proposals were unfunded. Most proposals were for secondary hypothesis-generating questions, with only 1 proposed reanalysis of the original study primary hypothesis. To date, 3 peer-reviewed articles have been published after a median of 19 months (9-32 months) from the data-sharing agreement.CONCLUSIONS: Despite availability of data from >500 cardiometabolic trials in a multisponsor data-sharing platform, only 15% of these trials and 29% of phase 3/4 trials have been accessed by investigators thus far, and a negligible minority of analyses have reached publication.



Cardiovascular Outcomes and Risks After Initiation of a Sodium Glucose Co-Transporter 2 Inhibitor: Results From the EASEL Population-Based Cohort Study [Original Research Article]

2017-11-13T06:37:45-08:00

Background: Clinical trials have shown cardiovascular benefits and potential risks from sodium glucose co-transporter 2 inhibitors (SGLT2i). Trials may have limited ability to address individual endpoints or safety concerns.Methods: We performed a population-based cohort study among type 2 diabetes patients with established cardiovascular disease newly initiated on antihyperglycemic agents (AHAs) within the US Department of Defense Military Health System between 4/1/2013 and 12/31/2016. Incidence rates, hazard ratios (HRs), and 95% confidence intervals (CIs) for time to first composite endpoint of all-cause mortality (ACM) and hospitalization for heart failure (HHF) event, major adverse cardiovascular events (MACE; defined as ACM, nonfatal myocardial infarction, and nonfatal stroke), and individual endpoints were evaluated using conditional Cox models comparing new SGLT2i users with other AHAs. Exploratory safety endpoint was below-knee lower extremity amputation (BKA). Intent-to-treat and on-treatment analyses were performed.Results: After propensity matching, 25,258 patients were followed for a median of 1.6 years. Compared with non-SGLT2i, initiation of SGLT2i was associated with a lower rate of ACM and HHF (1.73 vs. 3.01 events per 100 person-years; HR 0.57; 95% CI: 0.50-0.65) and MACE (2.31 vs. 3.45 events per 100 person-years; HR 0.67, 95% CI: 0.60-0.75). SGLT2i initiation was also associated with a ≈two-fold higher risk of BKA (0.17 vs. 0.09 events per 100 person-years; HR 1.99, 95% CI: 1.12-3.51). Due to the disproportionate canagliflozin exposure in the database, the majority of amputations were observed on canagliflozin. Results were consistent in the on-treatment analysis.Conclusions: In this high-risk cohort, initiation of SGLT2i was associated with lower ACM, HHF, and MACE and higher BKA risk. Findings underscore the potential benefit and risks to be aware of when initiating SGLT2i. It remains unclear whether the BKA risk extends across the class of medication as the study was not powered to make comparisons among individual treatments.



PCSK9 Variants, LDL-Cholesterol, and Neurocognitive Impairment: The REasons for Geographic and Racial Differences in Stroke (REGARDS) Study [Original Research Article]

2017-11-16T02:00:25-08:00

Background—Despite concerns about adverse neurocognitive events raised by prior trials, pharmacologic PCSK9 inhibition was not associated with neurocognitive effects in a recent phase 3 randomized trial. PCSK9 loss-of-function (LOF) variants that result in life-long exposure to low LDL-C can provide information on the potential long-term effects of low LDL-C on neurocognitive impairment and decline.Methods—We investigated the association between PCSK9 LOF variants and neurocognitive impairment and decline among African-American REasons for Geographic and Racial Differences in Stroke (REGARDS) study participants with (n=241) and without (n=10,454) C697X or Y142X LOF variants. Neurocognitive tests included Consortium to Establish a Registry for Alzheimer's Disease (CERAD) battery (Word List Learning, Delayed Recall, Animal Fluency) and Six Item Screener (SIS) assessments, administered longitudinally during follow-up. Neurocognitive impairment was defined as a score ≥ 1.5 standard deviations (SD) below age, sex, and education-based stratum-specific means on 2 or 3 CERAD assessments, or, separately, a score <5 on any SIS assessment at baseline or during follow-up. Neurocognitive decline was assessed using standardized continuous scores on individual neurocognitive tests.Results—The mean sample age was 64 years (SD 9), 62% were women, and the prevalence of neurocognitive impairment at any assessment was 6.3% by CERAD and 15.4% by SIS definitions. Adjusted odds ratios (ORs) for neurocognitive impairment for participants with versus without PCSK9 LOF variants were 1.11 (95% CI 0.58, 2.13) using the CERAD battery and 0.89 (95% CI 0.61, 1.30) using the SIS assessment. Standardized average differences in individual neurocognitive assessment scores over the 5.6 year (range 0.1, 9.1) study period ranged between 0.07 (95% CI -0.06, 0.20) and -0.07 (95% CI -0.18, 0.05) among participants with versus without PCSK9 LOF variants. Patterns of neurocognitive decline were similar between participants with and without PCSK9 LOF variants (all p > 0.10). ORs for neurocognitive impairment per 20 mg/dL LDL-C decrements were 1.02 (95% CI 0.96, 1.08) and 0.99 (95% CI 0.95, 1.02) for the CERAD and SIS definitions of impairment, respectively. Conclusions—These results suggest life-long exposure to low PCSK9 levels and cumulative exposure to lower LDL-C are not associated with neurocognitive effects in African Americans.



Long Term Outcomes in Patients with Type 2 Myocardial Infarction and Myocardial Injury [Original Research Article]

2017-11-20T08:30:19-08:00

Background—Type 2 myocardial infarction and myocardial injury are common in clinical practice, but long-term consequences are uncertain. We aimed to define long-term outcomes and explore risk stratification in patients with type 2 myocardial infarction and myocardial injury. Methods—We identified consecutive patients (n=2,122) with elevated cardiac troponin I concentrations (≥0.05 μg/L) at a tertiary cardiac center. All diagnoses were adjudicated as per the Universal Definition of Myocardial Infarction. The primary outcome was all-cause death. Secondary outcomes included major adverse cardiovascular events (MACE; non-fatal myocardial infarction or cardiovascular death) and non-cardiovascular death. To explore competing risks, cause-specific hazard ratios were obtained using Cox regression models.Results—The adjudicated index diagnosis was type 1 or type 2 myocardial infarction or myocardial injury in 1,171 (55.2%), 429 (20.2%) and 522 (24.6%) patients, respectively. At five years, all-cause death rates were higher in those with type 2 myocardial infarction (62.5%) or myocardial injury (72.4%) compared with type 1 myocardial infarction (36.7%). The majority of excess deaths in those with type 2 myocardial infarction or myocardial injury were due to non-cardiovascular causes (HR 2.32, 95%CI 1.92-2.81, versus type 1 myocardial infarction). Despite this, the observed crude MACE rates were similar between groups (30.6% versus 32.6%), with differences apparent after adjustment for co-variates (HR 0.82, 95%CI 0.69-0.96). Coronary heart disease was an independent predictor of MACE in those with type 2 myocardial infarction or myocardial injury (HR 1.71, 95%CI 1.31-2.24).Conclusions—Despite an excess in non-cardiovascular death, patients with type 2 myocardial infarction or myocardial injury have a similar crude rate of major adverse cardiovascular events to those with type 1 myocardial infarction. Identifying underlying coronary heart disease in this vulnerable population may help target therapies that could modify future risk.



Angiography versus Hemodynamics to Predict the Natural History of Coronary Stenoses: A FAME 2-Substudy [Original Research Article]

2017-11-21T02:00:20-08:00

Background—Among patients with documented stable coronary artery disease (CAD) and in whom no revascularization was performed, we compared the respective values of angiographic diameter stenosis (DS) and of fractional flow reserve (FFR) in predicting natural history. Methods—The present analysis included the 607 patients from the Fractional flow reserve versus angiography in multivessel evaluation 2 (FAME 2) trial in whom no revascularization was performed. FFR varied from 0.20 to 1.00 (average 0.74 ± 0.16) and DS (by QCA) varied from 8% to 98% (average 53 ± 15). The primary end point, defined as VOCE (Vessel oriented clinical endpoint) at 2 years, was a composite of prospectively adjudicated cardiac death, vessel-related myocardial infarction, vessel-related urgent and not urgent revascularization. The stenoses were divided into 4 groups according to FFR and %DS values: Positive Concordance (PC: FFR≤0.80; DS≥50%); Negative Concordance (NC: FFR>0.80; DS<50%); Positive Mismatch (PM: FFR≤0.80; DS<50%); Negative Mismatch (NM: FFR>0.80; DS≥50%). Results—The rate of VOCE was highest in the PC group (Log Rank: X2=80.96; p=0.001), and lowest in the NC group. The rate of VOCE was higher in the PM group than in the NM group (H.R. 0.38, 95% C.I. 0.21 - 0.67; p=0.001). There was no significant difference in VOCE between the PC and the PM (both groups with FFR≤0.80, H.R. 0.77, 95% C.I. 0.57 - 1.09; p=0.149) and no significant difference in rate of VOCE between the NM and NC (both groups with FFR>0.80, H.R. 1.89, 95% C.I. 0.96 - 3.74; p=0.067). Conclusions—In patients with stable coronary disease, physiology (FFR) is a more important determinant of the natural history of coronary stenoses than anatomy (DS). Clinical Trial Registration—URL: https://clinicaltrials.gov Unique Identifier: NCT01132495.



HDL Subspecies Defined by Presence of Apolipoprotein C-III and Incident Coronary Heart Disease in Four Cohorts [Original Research Article]

2017-11-21T02:00:23-08:00

Background—The causal role of high density lipoprotein (HDL) cholesterol in cardioprotection has been questioned by genetic and randomized studies. Novel measures that relate to HDL function may contribute new information to prediction of cardiovascular risk. Apolipoprotein C-III (apoC-III) is a key regulator of lipoprotein metabolism. We investigated whether subspecies of HDL defined by apoC-III are associated with coronary heart disease (CHD). Methods—We used immuno-affinity chromatography to measure the apoA-I concentrations of HDL that contains and lacks apoC-III in two prospective studies of adults free of CHD. In the Multi-Ethnic Study of Atherosclerosis (MESA), 5,657 participants (52% women; age 52-72 y) were followed for risk of CHD from 2000-2002 through 2013. In a case-cohort study nested within the Danish Diet, Cancer and Health (DCH) study, 3,642 participants (47% women; age 51-64 y) were followed from 1994-1997 through 2010. Subsequently, we conducted a meta-analysis that combined these results with the previously published findings from two cohort studies that used similar laboratory methodology to measure lipoproteins, totaling 2,997 incident cases. Results—ApoC-III was found on 6-8% of apoA-I. The two HDL subspecies showed opposing associations with risk of CHD in each of the individual cohorts and in the meta-analysis (p-heterogeneity between the two subspecies <0.01). HDL that contains apoC-III was associated with higher risk of CHD (pooled relative risk [RR] per SD = 1.09, 95% confidence interval [95% CI] = 1.01 to 1.18), whereas HDL that lacks apoC-III was associated with lower risk (RR= 0.76; 95% CI = 0.70 to 0.83). The relative risk for HDL lacking apoC-III was even more negative than the relative risk for total HDL (RR= 0.80; 95% CI = 0.74 to 0.87). Conclusions—Our findings from four prospective studies support the hypothesis that apoC-III may mark a subfraction of HDL that is associated with higher risk of CHD. New measures reflecting HDL structure and function may provide novel insights for cardiovascular risk that extend beyond traditional plasma HDL cholesterol concentrations.



Surgical Enlargement of the Aortic Root Does Not Increase the Operative Risk of Aortic Valve Replacement [Original Research Article]

2017-11-22T02:00:22-08:00

Background—Surgical aortic root enlargement (ARE) during aortic valve replacement (AVR) allows for larger prosthesis implantation and may be an important adjunct to surgical AVR in the transcatheter valve-in-valve era. The incremental operative risk of adding ARE to AVR has not been established. We sought to evaluate the early outcomes of patients undergoing AVR with or without ARE.Methods—From January 1990 to August 2014, 7039 patients underwent AVR (AVR + ARE, n=1854; AVR, n=5185) at a single institution. Patients with aortic dissection and active endocarditis were excluded. Mean age was 65±14 years and 63% were male. Logistic regression and propensity score matching were used to adjust for unbalanced variables in group comparisons.Results—Patients undergoing AVR + ARE were more likely to be female (46% vs. 34%, p<0.001) and had higher rates of previous cardiac surgery (18% vs 12%, p<0.001), COPD (5% vs. 3%, p=0.004), urgent/emergent status (6% vs 4%, p=0.01), and worse NYHA status (p<0.001). Most patients received bioprosthetic valves (AVR + ARE: 73.4% vs. AVR: 73.3%, p=0.98) and also underwent concomitant cardiac procedures (AVR+ARE: 68% vs. AVR: 67%, p=0.31). Mean prosthesis size implanted was slightly smaller in patients requiring AVR + ARE vs. AVR (23.4±2.1 vs. 24.1±2.3, p<0.001). In-hospital mortality was higher following AVR + ARE (4.3% vs. 3.0%, p=0.008), although when the cohort was restricted to patients undergoing isolated aortic valve replacement with or without root enlargement, mortality was not statistically different (AVR + ARE: 1.7% vs. AVR: 1.1%, p=0.29). Following adjustment for baseline characteristics, AVR + ARE was not associated with an increased risk of in-hospital mortality when compared with AVR (Odds Ratio 1.03, 95% CI (0.75-1.41), p=0.85). Furthermore, AVR + ARE was not associated with an increased risk of post-operative adverse events. Results were similar if propensity matching was used instead of multivariable adjustments for baseline characteristics.Conclusions—In the largest analysis to date, ARE was not associated with increased risk of mortality or adverse events. Surgical ARE is a safe adjunct to AVR in the modern era.



Impact of Lipid Measurements in Youth in Addition to Conventional Clinic-Based Risk Factors on Predicting Preclinical Atherosclerosis in Adulthood: The International Childhood Cardiovascular Cohort (i3C) Consortium [Original Research Article]

2017-11-23T02:00:24-08:00

Background—Data suggest that the prediction of adult cardiovascular disease using a model comprised entirely of adult non-laboratory based risk factors is equivalent to an approach that additionally incorporates adult lipid measures. We assessed and compared the utility of a risk model based solely on non-laboratory risk factors in adolescence vs. a lipid model based on non-laboratory risk factors + lipids for predicting high-risk carotid intima-media thickness (cIMT) in adulthood.Methods—The study comprised 2,893 participants aged 12-18 years from four longitudinal cohort studies from the United States (Bogalusa Heart Study and the Insulin Study), Australia (Childhood Determinants of Adult Health Study) and Finland (The Cardiovascular Risk in Young Finns Study) and followed into adulthood when cIMT was measured (mean follow-up 23.4 years). Overweight status was defined according to the Cole classification. Hypertension was defined according to the Fourth Report on High Blood Pressure in Children and Adolescents from the National High Blood Pressure Education Program. High-risk plasma lipid levels were defined according to the National Cholesterol Education Program (NCEP) Expert Panel on Cholesterol Levels in Children. High cIMT was defined as a study-specific value ≥90th percentile. Age-and sex were included in each model.Results—In univariate models all risk factors except for borderline high-and high triglycerides in adolescence were associated with high cIMT in adulthood. In multivariable models (RR [95% CI]), male sex (2.7 [2.0-2.6]), pre-hypertension (1.4 [1.0-1.9]), hypertension (1.9 [1.3-2.9]), overweight (2.0 [1.4-2.9]), obesity (3.7 [2.0-7.0]), borderline high LDL-cholesterol (1.6 [1.2-2.2]), high LDL-cholesterol (1.6 [1.1-2.1]) and borderline low HDL-cholesterol (1.4 [1.0-1.8]) remained significant predictors of high cIMT (P always < 0.05). The addition of lipids into the non-laboratory risk model slightly, but significantly, improved discrimination in predicting high cIMT compared with non-laboratory-based risk factors only (c-statistics for laboratory-based model 0.717 [95%CI 0.685-0.748] and for non-laboratory 0.698 [95%CI 0.667-0.731], P=0.02).Conclusions—Non-laboratory-based risk factors and lipids measured in adolescence independently predicted preclinical atherosclerosis in young adulthood. The addition of lipid measurements to traditional clinic based risk factor assessment provided a statistically significant but clinically modest improvement on adolescent prediction of high cIMT in adulthood.



The Novel Desmin Mutation p.Glu401Asp Impairs Filament Formation, Disrupts Cell Membrane Integrity and Causes Severe Arrhythmogenic Left Ventricular Cardiomyopathy/Dysplasia [Original Research Article]

2017-12-06T01:55:20-08:00

Background—Desmin (DES) mutations cause severe skeletal and cardiac muscle disease with heterogeneous phenotypes. Recently, DES mutations were described in patients with inherited arrhythmogenic right ventricular cardiomyopathy/dysplasia (iARVC/D), although their cellular and molecular pathomechanisms are not precisely known. Our aim is to describe clinically and functionally the novel DES-p.Glu401Asp mutation as a cause of inherited left ventricular arrhythmogenic cardiomyopathy/dysplasia (iLVAC/D).Methods—We identified the novel DES mutation p.Glu401Asp in a large Spanish family with iLVAC/D and a high incidence of adverse cardiac events. A full clinical evaluation was performed on all mutation carriers and non-carriers to establish clinical and genetic co-segregation. In addition, desmin and intercalar disc-related proteins expression were histologically analyzed in explanted cardiac tissue affected by the DES mutation. Furthermore, mesenchymal stem cells were isolated and cultured from two family members with the DES mutation (one with mild and one with severe symptomatology) and a member without the mutation (control) and differentiated ex vivo to cardiomyocytes. Then, important genes related to cardiac differentiation and function were analyzed by qRT-PCR. Finally, the p.Glu401Asp mutated DES gene was transfected into cells lines and analyzed by confocal microscopy.Results—66 family members were screened for the DES-p.Glu401Asp mutation, 23 of them were positive, 6 were obligate carriers and 2 were likely carriers. 100 % of genotype positive patients presented data consistent with inherited arrhythmogenic cardiomyopathy/dysplasia (iAC/D) phenotype with variable disease severity expression, high incidence sudden cardiac death and absence of skeletal myopathy or conduction system disorders. Immunohistochemistry was compatible with iAC/D, and the functional study showed an abnormal growth pattern and cellular adhesion, reduced desmin RNA expression, as well as some other membrane proteins, and desmin aggregates in transfected cells expressing the mutant desmin.Conclusions—The DES-p.Glu401Asp mutation causes predominant iLVAC/D with a high incidence of adverse clinical events in the absence of skeletal myopathy or conduction system disorders. The pathogenic mechanism probably corresponds to an alteration in desmin dimer and oligomer assembly and its connection with membrane proteins within the intercalated disc.



Effect of Losartan on RV Dysfunction: Results from the Double-Blind, Randomized REDEFINE Trial in Adults with Repaired Tetralogy of Fallot [Original Research Article]

2017-12-08T01:55:20-08:00

Background—The effect of angiotensin II receptor blockers (ARBs) on right ventricular (RV) function is still unknown. ARBs are beneficial in patients with acquired left ventricular (LV) dysfunction and recent findings suggested a favorable effect in symptomatic patients with systemic RV dysfunction. The current study aimed to determine the effect of losartan, an ARB, on subpulmonary RV dysfunction in adults after repair of tetralogy of Fallot (rTOF).Methods—REDEFINE is an investigator-initiated, multicenter, prospective, 1:1 randomized, double-blind, placebo-controlled study. Adults with rTOF and RV dysfunction (RV ejection fraction (EF) <50%) but without severe valvular dysfunction were eligible. Patients were randomized between losartan (150mg daily) and placebo with target treatment duration between 18-24 months. The primary outcome was RV EF change, determined by cardiovascular magnetic resonance imaging in intention-to-treat analysis. Results—Of 95 included patients, 47 patients received 150mg losartan daily (age: 38.0±12.4 years, 74% male), and 48 patients received placebo (age: 40.6±11.4, 63% male). Overall, RV EF did not change in patients allocated to losartan (n=42) (44.4±5.1% to 45.2±5.0%) and placebo (n=46) (43.2±6.3% to 43.6±6.9%). Losartan did not significantly improve RV EF compared to placebo (+0.51%, 95% CI:-1.0, +2.0, p=0.50). No significant treatment effects were found on secondary outcomes: left ventricular EF, peak aerobic exercise capacity, and N-terminal pro brain natriuretic peptide (p>0.30 for all). In predefined subgroup analyses, losartan did not have a statistically significant impact on RV EF in subgroups with: symptoms, restrictive RV, RV EF<40%, PVR, or QRS fragmentation. However, in a post hoc analysis, losartan was associated with improved RV EF in a subgroup (n=30) with non-restrictive RV and incomplete remodeling (QRS fragmentation and previous pulmonary valve replacement) (+2.7%, 95 CI:+0.1,+5.4, p=0.045).Conclusions—Losartan had no significant effect on RV dysfunction or secondary outcome parameters in rTOF. Future larger studies may determine whether there might be a role for losartan in specific vulnerable subgroups. Clinical Trial Registration—URL: https://clinicaltrials.gov Unique Identifier: NCT02010905



Targeting TMBIM1 Alleviates Pathological Cardiac Hypertrophy [Original Research Article]

2017-12-11T02:00:22-08:00

Background—Cardiac hypertrophy and its resultant heart failure are among the most common causes of mortality worldwide. Abnormal protein degradation, especially the impaired lysosomal degradation of large organelles and membrane proteins, is involved in the progression of cardiac hypertrophy. However, the underlying mechanisms have not been fully elucidated.Methods—We investigated cardiac TMBIM1 mRNA and protein expression levels in samples from patients with heart failure and mice with aortic banding (AB)-induced cardiac hypertrophy. We generated cardiac-specific Tmbim1 knockout mice and cardiac-specific Tmbim1-overexpressing transgenic mice and then challenged them with AB surgery. We used microarray, confocal image, co-immunoprecipitation analyses to identify the downstream targets of TMBIM1 in cardiac hypertrophy. Tmbim1/Tlr4 double knockout (DKO) mice were generated to investigate whether the effects of TMBIM1 on cardiac hypertrophy were TLR4 dependent. Finally, lentivirus-mediated TMBIM1 overexpression in monkey AB model was performed to evaluate the therapeutic potential of TMBIM1.Results—TMBIM1 expression was significantly downregulated upon hypertrophic stimuli in both human and mice heart samples. Silencing cardiac Tmbim1 aggravated AB-induced cardiac hypertrophy. This effect was blunted by Tmbim1 overexpression. Transcriptome profiling revealed that the TLR4 signaling pathway was disrupted dramatically by manipulating Tmbim1. The effects of TMBIM1 on cardiac hypertrophy were shown to be dependent on TLR4 in DKO mice. Fluorescent staining indicated that TMBIM1 promoted the lysosome-mediated degradation of activated TLR4. Co-immunoprecipitation assays confirmed that TMBIM1 directly interacted with TSG101 via a PTAP motif and accelerated the formation of multivesicular bodies (MVBs) that delivered TLR4 to the lysosomes. Finally, lentivirus-mediated TMBIM1 overexpression reversed AB-induced cardiac hypertrophy in monkeys.Conclusions—TMBIM1 protects against pathological cardiac hypertrophy through promoting the lysosomal degradation of activated TLR4. Our findings reveal the central role of TMBIM1 as a MVB regulator in the progression of pathological cardiac hypertrophy, as well as the role of vesicle trafficking in signaling regulation during cardiac hypertrophy. Moreover, targeting TMBIM1 could be a novel therapeutic strategy for treating cardiac hypertrophy and heart failure.



Large Cardiac-Muscle Patches Engineered from Human Induced-Pluripotent Stem-Cell-Derived Cardiac Cells Improve Recovery from Myocardial Infarction in Swine [Original Research Article]

2017-12-12T02:00:21-08:00

Background—Here, we generated human cardiac muscle patches (hCMPs) of clinically relevant dimensions (4 cm × 2 cm × 1.25 mm) by suspending cardiomyocytes, smooth-muscle cells, and endothelial cells that had been differentiated from human induced-pluripotent stem cells (hiPSCs) in a fibrin scaffold and then culturing the construct on a dynamic (rocking) platform.Methods—In vitro assessments of hCMPs suggest maturation in response to dynamic culture stimulation. In vivo assessments were conducted in a porcine model of myocardial infarction (MI). Animal groups included: MI hearts treated with two hCMPs (MI+hCMP, N=13), treated with two cell-free open fibrin patches (MI+OP, n=14), or with neither experimental patches (MI, n=15); a fourth group of animals underwent sham surgery (SHAM, n=8). Cardiac function and infarct size were evaluated by magnetic resonance imaging, arrhythmia incidence by implanted loop recorders, and the engraftment rate by calculation of quantitative PCR measurements of expression of the human Y chromosome. Additional studies examined the myocardial protein expression profile changes and potential mechanisms of action that related with exosomes from the cell patch.Results—The hCMPs began to beat synchronously within 1 day of fabrication, and after 7 days of dynamic culture stimulation, in vitro assessments indicated the mechanisms related to the improvements in electronic mechanical coupling, calcium-handling, and force-generation suggesting a maturation process during the dynamic culture. The engraftment rate was 10.9±1.8% at 4 weeks after the transplantation. The hCMP transplantation was associated with significant improvements in left ventricular (LV) function, infarct size, myocardial wall stress, myocardial hypertrophy, and reduced apoptosis in the peri-scar boarder zone myocardium. hCMP transplantation also reversed some MI-associated changes in sarcomeric regulatory protein phosphorylation. The exosomes released from the hCMP appeared to have cytoprotective properties that improved cardiomyocyte survival.Conclusions—We have fabricated a clinically relevant size of hCMP with trilineage cardiac cells derived from hiPSCs. The hCMP matures in vitro during 7 days of dynamic culture. Transplantation of this type of hCMP results in significantly reduced infarct size and improvements in cardiac function that are associated with reduction in LV wall stress. The hCMP treatment is not associated with significant changes in arrhythmogenicity.



Particulate Matter Air Pollution Exposure and Heart Disease Mortality Risks by Race and Ethnicity in the United States: 1997-2009 NHIS with Mortality Followup Through 2011 [Original Research Article]

2017-12-13T02:00:26-08:00

Background—Most U.S. studies of mortality and air pollution have been conducted on largely non-Hispanic white study populations. However, many health and mortality outcomes differ by race and ethnicity, and non-Hispanic white persons experience lower air pollution exposures than those who are non-Hispanic black or Hispanic. This study examines whether associations between air pollution and heart disease mortality differ by race/ethnicity. Methods—We used data from the 1997-2009 National Health Interview Survey linked to mortality records through December 2011 and annual estimates of fine particulate matter (PM2.5) by Census tract. Proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) between PM2.5 (per 10 μg/m3) and heart disease mortality using the full sample and the sample adults, which have information on additional health variables. Interaction terms were used to examine differences in the PM2.5-mortality association by race/ethnicity.Results—Overall, 65,936 of the full sample died during follow-up and 22,152 died from heart disease. After adjustment for several factors, we found a significant positive association between PM2.5 and heart disease mortality (HR 1.16 95% CI 1.08-1.25). This association was similar in sample adults with adjustment for smoking and body mass index (HR 1.18 95% CI 1.06-1.31). Interaction terms for non-Hispanic black and Hispanic groups compared to the non-Hispanic white group were not statistically significant. Conclusions—Using a nationally representative sample, the association between PM2.5 and heart disease mortality was elevated and similar to previous estimates. Associations for non-Hispanic black and Hispanic adults were not statistically significantly different from that for non-Hispanic white adults.



NT-proBNP-Guided Therapy in Acute Decompensated Heart Failure: The PRIMA II Randomized Controlled Trial [Original Research Article]

2017-12-14T02:00:21-08:00

Background—The concept of natriuretic peptide guidance has been extensively studied in chronic heart failure (HF) patients, with only limited success. The effect of NT-proBNP-guided therapy in acute decompensated HF (ADHF) patients using a relative NT-proBNP target has not been investigated. The aim of this study was to assess whether NT-proBNP-guided therapy of ADHF patients using a relative NT-proBNP target would lead to improved outcome compared with conventional therapy.Methods—We conducted a prospective randomized, controlled trial to study the impact of in-hospital guidance for ADHF treatment by a predefined NT-proBNP target (>30% reduction from admission to discharge) versus conventional treatment. ADHF patients with NT-proBNP levels of > 1700 ng/L were eligible. After achieving clinical stability, 405 patients were randomized to either NT-proBNP-guided or conventional treatment (1:1). The primary endpoint was dual, i.e. a composite of all-cause mortality and HF readmissions in 180 days, and the number of days alive out of the hospital in 180 days. Secondary endpoints were all-cause mortality within 180 days, HF readmissions within 180 days, and a composite of all-cause mortality and HF readmissions within 90 days. Results—Significantly more patients in the NT-proBNP-guided therapy group were discharged with an NT-proBNP reduction of >30% (80% versus 64%, P=0.001). Nonetheless, NT-proBNP-guided therapy did not significantly improve the combined event rate for all-cause mortality and HF readmissions (HR for NT-proBNP-guided therapy, 0.96; 95% CI, 0.72 to 1.37; P=0.99), or the median number of days alive outside of the hospital (178 vs. 179 days for NT-proBNP vs. conventional patients, P=0.39). Guided therapy also did not significantly improve any of the secondary endpoints. Conclusions—The PRIMA II demonstrates that that guidance of HF therapy to reach an NT-proBNP reduction of >30% after clinical stabilization did not improve 6-months outcome. Clinical Trial Registration—URL: http://www.trialregister.nl Unique Identifier: NTR3279



Second Arterial versus Venous Conduits for Multi-Vessel Coronary Artery Bypass Surgery in California [Original Research Article]

2017-12-14T02:00:25-08:00

Background—Whether a second arterial conduit improves outcomes after multi-vessel coronary artery bypass grafting remains unclear. Consequently, arterial conduits other than the left internal thoracic artery are seldom used in the United States.Methods—Using a state-maintained clinical registry including all 126 non-federal hospitals in California, we compared all-cause mortality and rates of stroke, myocardial infarction, repeat revascularization, and sternal wound infection between propensity score-matched cohorts who underwent primary, isolated multi-vessel coronary artery bypass grafting with the left internal thoracic artery, and who received a second arterial conduit (right internal thoracic artery or radial artery, N=5,866) or a venous conduit (N=53,566) between 2006 and 2011. Propensity score matching using 34 preoperative characteristics yielded 5,813 matched sets. A sub-group analysis compared outcomes between propensity score-matched recipients of a right internal thoracic artery (N=1,576) or a radial artery (N=4,290).Results—Second arterial conduit use decreased from 10.7% in 2006 to 9.1% in 2011 (p<0.0001). However, receipt of a second arterial conduit was associated with significantly lower mortality (13.1% vs. 10.6% at 7 years; HR 0.79, 95% CI 0.72-0.87), and lower risks of myocardial infarction (HR 0.78, 95% CI 0.70-0.87) and repeat revascularization (HR 0.82, 95% CI 0.76-0.88). Compared with radial artery grafts, right internal thoracic artery grafts were associated with similar mortality rates (right internal thoracic artery 10.3% vs. radial artery 10.7% at 7 years; HR 1.10, 95% CI 0.89-1.37) and individual risks of cardiovascular events, but the risk of sternal wound infection was increased (risk difference 1.07%, 95% CI 0.15%-2.07%).Conclusions—Second arterial conduit use in California is low and declining, but arterial grafts were associated with significantly lower mortality and fewer cardiovascular events. A right internal thoracic artery graft offered no benefit over that of a radial artery, but did increase risk of sternal wound infection. These findings suggest surgeons should consider lowering their threshold for using arterial grafts, and the radial artery may be the preferred second conduit.



Global Pulmonary Vascular Remodeling in Pulmonary Hypertension Associated with Heart Failure and Preserved or Reduced Ejection Fraction [Original Research Article]

2017-12-15T02:00:20-08:00

Background—We hypothesized that pulmonary venous hypertension in heart failure (HF) leads to predominate remodeling of pulmonary veins and that the severity of venous remodeling is associated with the severity of pulmonary hypertension (PH) in HF.Methods—Patients with HF (n=108; 53 preserved and 55 reduced ejection fraction) with PH (HF-PH; pulmonary artery systolic pressure (PASP) ≥ 40 mmHg) were compared to normal Controls (n=12) and patients with primary pulmonary veno-occlusive disease (PVOD; n=17). In lung specimens from autopsy (Control, HF-PH and 7 PVOD) or surgery (10 PVOD), quantitative histomorphometry was performed in all analyzable arteries (n=4,949), veins (n=7,630) and small indeterminate vessels (IV, n=2,168) to define % medial thickness (%MT) [arteries] and % intimal thickness (%IT) [arteries, veins and IV] relative to external diameter. Results—The average arterial %MT (Control 6.9; HF-PH 11.0; PVOD 15.0); arterial %IT (Control 4.9; HF-PH 14.9; PVOD 31.1); venous %IT (Control 14.0; HF-PH 24.9; PVOD 43.9) and IV %IT (Control 10.6; HF-PH 25.8; PVOD 50.0) in HF-PH were higher than Controls (p<0.0001 for all) but lower than PVOD (p≤0.005 for all). PASP (mmHg) was lower in HF-PH (median 59 [IQR 50-70]) than PVOD (91 [82-103]). PASP correlated with arterial %MT (r=0.41) and arterial %IT (r=0.35) but more strongly with venous %IT (r=0.49) and IV %IT (r=0.55) (p<0.0001 for all). Associations between PASP and venous or IV %IT remained significant after adjusting for arterial %MT and %IT and did not vary by HF type. In patients with right heart catheterization (30 HF-PH; 14 PVOD) similar associations between the transpulmonary gradient and pulmonary vascular remodeling existed, with numerically stronger associations for venous and IV %IT. While the PASP was slightly higher in HF-PH patients with right ventricular dysfunction, pulmonary vascular remodeling was not more severe. Pulmonary vascular remodeling severity was associated with reductions in the diffusing capacity of the lungs. Conclusions—In HF, PH is associated with global pulmonary vascular remodeling but the severity of PH correlates most strongly with venous and small IV intimal thickening, similar to the pattern observed in PVOD. These findings expand our understanding of the pathobiology of PH in HF.



miRNA-22 is a Novel Mediator of Vascular Smooth Muscle Cell Phenotypic Modulation and Neointima Formation [Original Research Article]

2017-12-15T02:00:23-08:00

Background—MicroRNA-22 (miR-22) has recently been reported to play a regulatory role during vascular smooth muscle cell (VSMC) differentiation from stem cells, but little is known about its target genes and related pathways in mature VSMC phenotypic modulation or its clinical implication in neointima formation following vascular injury. Methods—We applied wire-injury mouse model as well as local delivery of AgomiR-22 or miR-22 inhibitor to explore the therapeutic potential of miR-22 in vascular diseases. Furthermore, normal and diseased human femoral arteries were harvested and various in vivo, ex vivo, and in vitro models of VSMC phenotype switching were conducted to examine miR-22 expression during VSMC phenotype switching. Results—Expression of miR-22 was closely regulated during VSMC phenotypic modulation. miR-22 over-expression significantly increased expression of VSMC marker genes and inhibited VSMC proliferation and migration, whilst the opposite effect was observed when endogenous miR-22 was knocked down. As expected, two previously reported miR-22 target genes, methyl-CpG binding protein 2 (MECP2) and histone deacetylase 4 (HDAC4), exhibited a regulatory role in VSMC phenotypic modulation. A transcriptional regulator and oncoprotein, Ecotropic Virus Integration Site 1 Protein Homolog (EVI1), has been identified as a novel miR-22 target gene in VSMC phenotypic modulation. Of note, overexpression of miR-22 in the injured vessels significantly reduced the expression of its target genes; decreased VSMC proliferation, and inhibited neointima formation in wire-injured femoral arteries, whilst the opposite effect was observed with local application of a miR-22 inhibitor to injured arteries. We next examined the clinical relevance of miR-22 expression and its target genes in human femoral arteries. We found that miR-22 expression was significantly reduced, while MECP2 and EVI1 expression levels were dramatically increased, in diseased compared to healthy femoral human arteries. This inverse relationship between miR-22 and MECP2 and/or EVI1 was evident in both healthy and diseased human femoral arteries. Conclusions—Our data demonstrates that miR-22 and EVI1 are novel regulators of VSMC function specifically during neointima hyperplasia, offering a novel therapeutic opportunity for treating vascular diseases.



The Genetic Architecture of the Cardiovascular Risk Proteome [Original Research Article]

2017-12-19T02:00:22-08:00

Background—We recently identified 156 proteins in human plasma that were each associated with the net Framingham Cardiovascular Disease (CVD) Risk Score (FRS) using an aptamer-based proteomic platform in Framingham Heart Study (FHS) Offspring participants. Here, we hypothesized that performing genome-wide association studies and exome array analyses on the levels of each these 156 proteins might identify genetic determinants of risk-associated circulating factors and provide insights into early cardiovascular pathophysiology.Methods—We studied the association of genetic variants with the plasma levels of each of the 156 FRS-associated proteins using linear mixed effects models in two population-based cohorts. We performed discovery analyses in 759 participants of the FHS Offspring cohort, an observational study of the adult children of the original FHS participants, and validated these findings in 1421 participants of the Malmö Diet and Cancer Study. To evaluate the utility of this strategy in identifying new biological pathways relevant to CVD pathophysiology, we performed studies in a cell-model system to experimentally validate the functional significance of an especially novel genetic association with circulating apolipoprotein E (ApoE) levels. Results—We identified 120 locus-protein associations in genome-wide analyses and 41 associations in exome array analyses, the majority of which have not been described previously. These loci explained up to 66% of inter-individual plasma protein level variation and, on average, accounted for three times the amount of variation explained by common clinical factors, such as age, sex, and diabetes status. We described overlap between many of these loci and CVD genetic risk variants. Finally, we experimentally validated a novel association between circulating ApoE levels and the transcription factor phosphatase 1G (PPM1G). Knockdown of PPM1G in a human liver cell model resulted in decreased ApoE transcription and ApoE protein levels in cultured supernatants.Conclusions—We identified dozens of novel genetic determinants of proteins associated with the FRS and experimentally validated a new role for PPM1G in lipoprotein biology. Further, genome-wide and exome array data for each protein has been made publicly available as a resource for CVD research.



Risk Factors of Sudden Cardiac Death in the Young: A Multiple-Year Community-Wide Assessment [Original Research Article]

2017-12-21T02:00:19-08:00

Background—Prevention of sudden cardiac arrest (SCA) in the young remains a largely unsolved public health problem and sports activity is an established trigger. While the presence of standard cardiovascular risk factors in the young can link to future morbidity and mortality in adulthood, the potential contribution of these risk factors to SCA in the young has not been evaluated. Methods—We prospectively ascertained subjects who suffered SCA between the ages of 5-34 years in the Portland, Oregon, USA metropolitan area (2002-2015, catchment population approximately 1 million). We assessed the circumstances, resuscitation outcomes and clinical profile of subjects that suffered SCA by a detailed evaluation of emergency response records, lifetime clinical records and autopsy examination. We specifically evaluated the association of standard cardiovascular risk factors and SCA, and sports as a trigger for SCA in the young.Results—Out of 3775 SCAs in all age groups, 186 (5%) occurred in the young (Mean age 25.9 ± 6.8, 67% male). In young SCA, overall prevalence of warning signs before SCA was low (29%); and 26 (14%) were associated with sports as a trigger. The remainder (n=160) occurred in other settings categorized as non-sports. Sports-related SCAs accounted for 39% of SCAs aged ≤18, 13% of SCAs aged 19-25, and 7% of SCAs aged 25-34. Sports-related SCA cases were more likely to present with shockable rhythms, and survival from cardiac arrest was 2.5-fold higher in sports-related vs. non-sports SCA (28% vs. 11%; p=0.05). Overall, the most common SCA-related conditions were sudden arrhythmic death syndrome (31%), coronary artery disease (22%) and hypertrophic cardiomyopathy (14%). There was an unexpectedly high overall prevalence of established cardiovascular risk factors (obesity, diabetes, hypertension, hyperlipidemia, smoking) with ≥1 risk factor in 58% of SCA cases. Conclusions—Sports was a trigger of SCA in a minority of cases, and in most patients SCA occurred without warning symptoms. Standard cardiovascular risk factors were found in over half of patients, suggesting the potential role of public health approaches that screen for cardiovascular risk factors at earlier ages.



Exposure to Low-Dose Ionizing Radiation from Cardiac Procedures and Malignancy Risk in Adults with Congenital Heart Disease [Original Research Article]

2017-12-21T02:00:20-08:00

Background—Adults with congenital heart disease (ACHD) are exposed to increasing amounts of low-dose ionizing radiation (LDIR) from cardiac procedures. Cancer prevalence in this population is higher compared to the general population. This study estimates the association between LDIR exposure from cardiac procedures and incident cancer in ACHD patients.Methods—The study population derived from the Quebec CHD Database. We measured cumulative numbers of LDIR-related cardiac procedures for each patient until one year before time of cancer diagnosis or administrative censoring. To assess the association between LDIR exposure and cancer risk, we conducted a nested case-control study and matched cancer cases with controls on sex, CHD severity, birth year and age.Results—The study included 24,833 ACHD patients aged 18-64 years from 1995-2009. In over 250,791 person-years of follow-up, 602 cancer cases were observed (median age: 55.4 years). The cumulative incidence of cancer estimated up to age 64 was 15.3% (95% CI, 14.2-16.5). Cases had more LDIR-related cardiac procedures than controls (1,410 versus 921 per 1,000 ACHD patients, p<0.0001). Cumulative LDIR exposure was independently associated with cancer (OR: 1.08 per procedure; 95% CI, 1.04-1.13). Similar results were obtained using dose estimates for LDIR exposure (OR: 1.10 per 10 milliSieverts; 95% CI, 1.05-1.15) with a possible dose related response. The effect measure was in the same direction and the association was persistent for exposure≥6 procedures in all sensitivity analyses: after excluding most smoking-related cancer cases (OR: 1.10 per procedure; 95% CI, 1.05-1.16 and OR when exposure≥6 procedures: 3.08; 95% CI, 1.77-5.37), and after applying a three-year lag period (OR: 1.09 per procedure; 95% CI, 1.03-1.14 and OR when exposure≥6 procedures: 2.58; 95% CI, 1.43-4.69).Conclusions—To our knowledge, this is the first large population-based study to analyze and document the association between LDIR-related cardiac procedures and incident cancer in ACHD population. Confirmations of these findings by prospective studies are needed to reinforce policy recommendations for radiation surveillance in CHD patients where no regulation currently exists. Physicians ordering and performing cardiac imaging should ensure that exposure is "as low as reasonably achievable" without sacrificing quality of care.



Association Between Prompt Defibrillation and Epinephrine Treatment With Long Term Survival After In-Hospital Cardiac Arrest [Original Research Article]

2017-12-26T02:00:21-08:00

Background—Prior studies have reported higher in-hospital survival with prompt defibrillation and epinephrine treatment in patients suffering in-hospital cardiac arrest (IHCA). Whether this survival benefit persists after discharge is unknown.Methods—We linked data from a national IHCA registry with Medicare files and identified 36,961 patients aged ≥65 years with an IHCA at 517 hospitals between 2000 and 2011. Patients with IHCA due to pulseless ventricular tachycardia (VT) or ventricular fibrillation (VF) were stratified by prompt (≤2 min) vs. delayed (>2 min) defibrillation, whereas patients with IHCA due to asystole or pulseless electrical activity (PEA) were stratified by prompt (≤ 5 min) vs. delayed (>5 min) epinephrine treatment. The association between prompt treatment and long-term survival for each rhythm type was assessed using multivariable hierarchical modified Poisson regression models. Results—Of 8119 patients with an IHCA due to VT/VF, the rate of 1-year survival was higher in those treated with prompt defibrillation than with delayed defibrillation (25.7% [1466/5714] vs. 15.5% [373/2405]; adjusted RR, 1.49 [1.32, 1.69]; p<0.0001). This survival advantage persisted at 3 years (19.1% vs. 11.0%; adjusted RR of 1.45; 95% CI: 1.23, 1.69; p<0.0001) and at 5 years (14.7% vs. 7.9%; adjusted RR of 1.50, 95% CI: 1.22, 1.83; p<0.0001). Of 28,842 patients with an IHCA due to asystole/PEA, the rate of 1-year survival with prompt epinephrine treatment was higher than with delayed treatment (5.4% [1341/24,885] vs. 4.3% [168/3957]; adjusted RR, 1.20 [1.02, 1.41]; p=0.02), but this survival benefit was no longer present at 3 years (3.5% vs. 2.9%; adjusted RR, 1.17 [0.95, 1.45]; p=0.15) and at 5 years (2.3% vs. 1.9%; adjusted RR. 1.18 [0.88, 1.58]; p=0.27). Conclusions—Prompt defibrillation for IHCA due to VT/VF was associated with higher rates of long-term survival throughout 5 years of follow-up, whereas prompt epinephrine treatment for asystole/PEA was associated with greater survival at 1 year, but not at 3 or 5 years. By quantifying the greater survival associated with timely defibrillation and epinephrine administration, these findings provide important insights on the durability of survival benefits for two process-of-care measures in current resuscitation guidelines.



Association Between Diastolic Blood Pressure During Pediatric In-Hospital Cardiopulmonary Resuscitation and Survival [Original Research Article]

2017-12-26T02:00:24-08:00

Background—Based on laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data demonstrating that survival depends on attaining adequate arterial diastolic blood pressure (DBP) during CPR, American Heart Association recommends using BP to guide pediatric CPR. However, evidence-based BP targets during pediatric CPR remain an important knowledge gap for CPR guidelines. Methods—All children ≥37 weeks gestation and <19 years old in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 minute and invasive arterial blood pressure monitoring prior to and during CPR between July 1, 2013 and June 31, 2016 were included. Mean DBP during CPR and Utstein-style standardized cardiac arrest data were collected. The hypothesis was that DBP ≥25 mmHg during CPR in infants and ≥30 mmHg in children ≥1 year old would be associated with survival. Primary outcome was survival to hospital discharge. Secondary outcome was survival to hospital discharge with favorable neurologic outcome, defined as Pediatric Cerebral Performance Categories 1-3 or no worse than pre-arrest baseline. Multivariable Poisson regression models with robust error estimates were used to estimate the relative risk of outcomes.Results—Blinded investigators analyzed BP waveforms during CPR from 164 children, including 60% <1 year old, 60% with congenital heart disease, and 54% post-cardiac surgery. Immediate cause of arrest was hypotension in 67%, respiratory decompensation in 44%, and arrhythmia in 19%. Median duration of CPR was 8 minutes [quartiles: 3 minutes, 27 minutes]. Ninety percent survived the event, 68% with return of spontaneous circulation and 22% by extracorporeal life support. Forty-seven percent survived to hospital discharge and 43% survived to discharge with favorable neurologic outcome. Maintaining mean DBP ≥25 mmHg in infants and ≥30 mmHg in children ≥1 year old occurred in 101/164 children (62%) and was associated with survival (adjusted Relative Risk [aRR] 1.7; 95% CI, 1.2-2.6; P=0.007) and survival with favorable neurologic outcome (aRR 1.6; 95% CI, 1.1-2.5; P=0.02).Conclusions—These data demonstrate that mean DBP ≥25 mmHg during CPR in infants and ≥30 mmHg in children ≥1 year old was associated with greater likelihood of survival to hospital discharge and survival with favorable neurologic outcome.



Improving 1-year Outcomes of Infrainguinal Limb Revascularisation: A Population-Based Cohort Study of 104 000 Patients in England [Original Research Article]

2018-01-09T02:00:22-08:00

Background—The availability and diversity of lower limb revascularisation procedures have increased in England in the past decade. We investigated whether these developments in care have translated to improvements in patient pathways and outcomes.Methods—Individual-patient records from Hospital Episode Statistics (HES) were used to identify 103 934 patients who underwent endovascular (angioplasty) or surgical (endarterectomy, profundaplasty or bypass) lower limb revascularisation for infrainguinal peripheral artery disease (PAD) in England between January 2006 and December 2015. Major lower limb amputations and deaths within 1 year following revascularisation were ascertained from HES and Office for National Statistics mortality records. Competing risks regression was used to estimate the cumulative incidence of major amputation and death, adjusted for patient age, sex, comorbidity score and indication for the intervention (intermittent claudication; severe limb ischaemia without tissue loss; severe limb ischaemia with ulceration; severe limb ischaemia with gangrene/osteomyelitis) and comorbid diabetes.Results—The estimated 1-year risk of major amputation reduced from 5.7% (in 2006-07) to 3.9% (in 2014-15) following endovascular revascularisation, and from 11.2% (2006-07) to 6.6% (2014-5) following surgical procedures. The risk of death after both types of revascularisation also reduced. These trends were observed for all indications categories, with the largest reductions found in patients with severe limb ischaemia with ulceration or gangrene. Overall, morbidity increased over the study period, and a larger proportion of patients were treated for the severe end of the PAD spectrum using less invasive procedures.Conclusions—Our findings show that from 2006 to 2015, the overall survival increased and the risk of major lower limb amputation decreased following revascularisation. These observations suggest that patient outcomes after lower limb revascularisation have improved during a period of centralisation and specialisation of vascular services in the United Kingdom.



miR-195 Regulates Metabolism in Failing Myocardium via Alterations in SIRT3 Expression and Mitochondrial Protein Acetylation [Original Research Article]

2018-01-12T02:00:23-08:00

Background—Heart failure (HF) leads to mitochondrial dysfunction and metabolic abnormalities of the failing myocardium coupled with an energy-depleted state and cardiac remodeling. The mitochondrial deacetylase sirtuin 3 (SIRT3) plays a pivotal role in the maintenance of mitochondrial function through regulating the mitochondrial acetylome. Interestingly, unique cardiac and systemic miRNAs have been shown to play an important role in cardiac remodeling by modulating key signaling elements in the myocardium. Methods—Cellular signaling was analyzed in human cardiomyocyte-like AC16 cells and acetylation levels in rodent models of SIRT3-/- and transgenic miR-195 overexpression were compared to WT. Luciferase assays, western blotting, immunoprecipitation assays and echocardiographic analysis were performed. Enzymatic activities of pyruvate dehydrogenase (PDH) and ATP synthase were measured.Results—In failing human myocardium, we observed induction of miR-195 along with decreased expression of the mitochondrial deacetylase SIRT3 that was associated with increased global protein acetylation. We further investigated the role of miR-195 in SIRT3-mediated metabolic processes and its impact on regulating enzymes involved in deacetylation. Proteomic analysis of the total acetylome showed increased overall acetylation, as well as specific lysine acetylation of two central mitochondrial metabolic enzymes: PDH and ATP synthase. miR-195 downregulates SIRT3 expression through direct 3'UTR targeting. Treatments with either sirtuin inhibitor nicotinamide, siRNA-mediated SIRT3 knockdown or miR-195 overexpression enhanced acetylation of PDH complex and ATP synthase. This effect diminished PDH and ATP synthase activity and impaired mitochondrial respiration. Consistently, SIRT3-/- and miR-195 transgenic mice showed enhanced global protein acetylation, including PDH complex and ATP synthase, associated with decreased enzymatic activity. Conclusions—Altogether, these data suggest that increased levels of miR-195 in failing myocardium regulate a novel pathway that involves direct SIRT3 suppression and enzymatic inhibition via increased acetylation of PDH and ATP synthase that are essential for cardiac energy metabolism.



High-Target vs Low-Target Blood Pressure Management During Cardiopulmonary Bypass to Prevent Cerebral Injury in Cardiac Surgery Patients - A Randomized Controlled Trial [Original Research Article]

2018-01-16T02:00:22-08:00

Background—Cerebral injury is an important complication following cardiac surgery with the use of cardiopulmonary bypass (CPB). The rate of overt stroke after cardiac surgery is 1-2%, whereas silent strokes, detected by diffusion-weighed magnetic resonance imaging (DWI), are found in up to 50% of patients. It is unclear if a higher versus a lower blood pressure during cardiopulmonary bypass reduces cerebral infarction in these patients.Methods—In a patient- and assessor-blinded randomized trial, we allocated patients to a higher (70-80 mmHg) or lower (40-50 mmHg) target for mean arterial pressure by the titration of norepinephrine during cardiopulmonary bypass. Pump flow was fixed at 2.4 L/min/m2. The primary outcome was the total volume of new ischemic cerebral lesions (sum in mm3), expressed as the difference between DWI conducted preoperatively and again postoperatively between day 3 and 6. Secondary outcomes included DWI-evaluated total number of new ischemic lesions.Results—Among the 197 enrolled patients, mean (SD) age was 65.0 (10.7) years in the low-target group (n=99) and 69.4 (8.9) years in the high-target group (n=98). Procedural risk scores were comparable between groups. Overall, DWI revealed new cerebral lesions in 52.8% of patients in the low-target group versus 55.7% in the high-target group (p = 0.76). The primary outcome of volume of new cerebral lesions was comparable between groups, 25 mm3 (interquartile range [IQR], 0-118; range 0-25261) in the low-target group vs 29 mm3 (IQR 0-143; range 0-22116) in the high-target group (median difference estimate, 0 (95% confidence interval [95% CI] -25 - 0.028); P=0.99), as was the secondary outcome of number of new lesions (1 (IQR 0-2; range 0-24) vs 1 (IQR 0-2; range 0-29) respectively; median difference estimate, 0 (95% CI 0 - 0); P=0.71). No significant difference was observed in frequency of severe adverse events.Conclusions—Among patients undergoing on-pump cardiac surgery, targeting a higher versus a lower MAP during cardiopulmonary bypass did not seem to affect the volume or numbers of new cerebral infarcts. Clinical Trial Registration—URL: http://www.clinicaltrials.gov Unique identifier: NCT02185885



Phosphoinositide 3-Kinase Gamma Inhibition Protects from Anthracycline Cardiotoxicity and Reduces Tumor Growth [Original Research Article]

2018-01-18T02:00:24-08:00

Background—Anthracyclines, such as doxorubicin (DOX), are potent anti-cancer agents for the treatment of solid tumors and hematological malignancies. However, their clinical use is hampered by cardiotoxicity. This study sought to investigate the role of PI3Kγ in DOX-induced cardiotoxicity and the potential cardio-protective and anti-cancer effects of PI3Kγ inhibition.Methods—Mice expressing a kinase-inactive PI3Kγ or receiving PI3Kγ selective inhibitors were subjected to chronic DOX treatment. Cardiac function was analyzed by echocardiography and DOX-mediated signaling was assessed in whole hearts or in isolated cardiomyocytes. The dual cardio-protective and anti-tumor action of PI3Kγinhibition was assessed in mouse mammary tumor models.Results—PI3Kγ KD mice showed preserved cardiac function after chronic low-dose DOX treatment, and were protected against DOX-induced cardiotoxicity. The beneficial effects of PI3Kγ inhibition were causally linked to enhanced autophagic disposal of DOX-damaged mitochondria. Consistently, either pharmacological or genetic blockade of autophagy in vivo abrogated the resistance of PI3Kγ KD mice to DOX cardiotoxicity. Mechanistically, PI3Kγ was triggered in DOX-treated hearts, downstream of TLR9, by the mitochondrial DNA released by injured organelles, and contained in autolysosomes. This autolysosomal PI3Kγ/Akt/mTOR/Ulk1 signaling provided maladaptive feedback inhibition of autophagy. Finally, PI3Kγ blockade in models of mammary gland tumors prevented DOX-induced cardiac dysfunction, and concomitantly synergized with the anti-tumor action of DOX, by unleashing anticancer immunity. Conclusions—Blockade of PI3Kγ may provide a dual therapeutic advantage in cancer therapy, by simultaneously preventing anthracyclines cardiotoxicity and reducing tumor growth.



Right Ventricular Myofilament Functional Differences in Humans with Systemic Sclerosis-associated versus Idiopathic Pulmonary Arterial Hypertension [Original Research Article]

2018-01-19T02:00:20-08:00

Background—Patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) have a far worse prognosis than those with idiopathic PAH (IPAH). In the intact heart, SSc-PAH exhibits depressed rest and reserve right ventricular (RV) contractility as compared to IPAH. We tested whether this disparity involves underlying differences in myofilament function. Methods—Cardiac myocytes were isolated from RV septal endomyocardial biopsies from patients with SSc-PAH, IPAH, or SSc with exertional dyspnea but no resting PAH (SSc-d); control RV septal tissue was obtained from non-diseased donor hearts (6-7/group). Isolated myocyte passive length-tension and developed tension-calcium relationships were determined and correlated with in vivo RV function and reserve. RV septal fibrosis was also examined. Results—Myocyte passive stiffness from length-tension relations was similarly increased in IPAH and SSc-PAH over control, although SSc-PAH biopsies had more interstitial fibrosis. More striking disparities were found between active force-calcium relations. Compared to controls, maximal calcium-activated force (Fmax) was 28% higher in IPAH but 37% lower in SSc-PAH. Fmax in SSc-d was intermediate between control and SSc-PAH. The calcium concentration required for half-maximal force (EC50) was similar between control, IPAH, and SSc-d, but lower in SSc-PAH. This disparity disappeared in myocytes incubated with the active catalytic subunit of protein kinase A. Myocyte Fmax directly correlated with in vivo RV contractility assessed by end-systolic elastance (Ees, R2=0.46, P=0.002) and change in Ees with exercise (R2=0.49, P=0.008), and was inversely related with exercise-induced chamber dilation (R2=0.63, P<0.002), the latter also a marker of depressed contractile reserve. Conclusions—A primary defect in human SSc-PAH resides in depressed sarcomere function, whereas this is enhanced in IPAH. These disparities correlate with in vivo RV contractility and contractile reserve, and are consistent with worse clinical outcomes in SSc-PAH. The existence of sarcomere disease prior to developing resting PAH in SSc-d patients suggests that earlier identification and intervention may prove useful.



Inhibition of Endothelial Notch Signaling Impairs Fatty Acid Transport and Leads to Metabolic and Vascular Remodeling of the Adult Heart [Original Research Article]

2018-01-20T02:00:22-08:00

Background—Nutrients are transported through endothelial cells before being metabolized in muscle cells. However, little is known about the regulation of endothelial transport processes. Notch signaling is a critical regulator of metabolism and angiogenesis during development. Here, we studied how genetic and pharmacological manipulation of endothelial Notch signaling in adult mice affects endothelial fatty acid transport, cardiac angiogenesis, and heart function.Methods—Endothelial-specific Notch inhibition was achieved by conditional genetic inactivation of Rbp-jκ in adult mice to analyze fatty acid metabolism and heart function. Wild-type mice were treated with neutralizing antibodies against the Notch ligand Dll4. Fatty acid transport was studied in cultured endothelial cells and transgenic mice.Results—Treatment of wild-type mice with Dll4 neutralizing antibodies for eight weeks impaired fractional shortening and ejection fraction in the majority of mice. Inhibition of Notch signaling specifically in the endothelium of adult mice by genetic ablation of Rbp-jκ caused heart hypertrophy and failure. Impaired heart function was preceded by alterations in fatty acid metabolism and an increase in cardiac blood vessel density. Endothelial Notch signaling controlled the expression of endothelial lipase, Angptl4, CD36 and Fabp4, which are all needed for fatty acid transport across the vessel wall. In endothelial-specific Rbp-jκ-mutant mice lipase activity and transendothelial transport of long-chain fatty acids to muscle cells was impaired. In turn, there was accumulation of lipids in plasma and liver. The attenuated supply of cardiomyocytes with long-chain fatty acids was accompanied by higher glucose uptake, increased concentration of glycolysis intermediates and mTOR-S6K signaling. Treatment with the mTOR inhibitor rapamycin or displacing glucose as cardiac substrate by feeding a ketogenic diet prolonged survival of endothelial-specific Rbp-jκ-deficient mice.Conclusions—This study identifies Notch signaling as a novel regulator of fatty acid transport across the endothelium and as an essential repressor of angiogenesis in the adult heart. The data imply that the endothelium controls cardiomyocyte metabolism and function.



Targeting Chondroitin Sulfate Glycosaminoglycans to Treat Cardiac Fibrosis in Pathological Remodeling [Original Research Article]

2018-01-25T02:00:22-08:00

Background—Heart failure (HF) is a leading cause of mortality and morbidity, and the search for novel therapeutic approaches continues. In the monogenic disease mucopolysaccharidosis (MPS) VI, loss of function mutations in arylsulfatase B (ASB) leads to myocardial accumulation of chondroitin sulfate (CS) glycosaminoglycans (GAGs), manifesting as a myriad of cardiac symptoms. Here, we studied changes in myocardial CS in non-MPS failing hearts, and assessed its generic role in pathological cardiac remodeling. Methods—Healthy and diseased human and rat left ventricles were subjected to histological and immuno-staining methods to analyze for GAG distribution. GAGs were extracted and analyzed for quantitative and compositional changes using Alcian Blue assay and liquid chromatography mass spectrometry. Expression changes in 20 CS-related genes were studied in three primary human cardiac cell types and THP-1 derived macrophages under each of 9 in vitro stimulatory conditions. In two rat models of pathological remodeling induced by transverse aortic constriction (TAC) or isoprenaline infusion, recombinant human arylsulfatase B (rhASB), clinically used as enzyme replacement therapy (ERT) in MPS VI, was administered intravenously for 7 or 5 weeks respectively. Cardiac function, myocardial fibrosis and inflammation were assessed by echocardiography and histology. CS-interacting molecules were assessed using surface plasmon resonance and a mechanism of action was verified in vitro. Results—Failing human hearts displayed significant perivascular and interstitial CS accumulation, particularly in regions of intense fibrosis. Relative composition of CS disaccharides remained unchanged. Transforming growth factor β (TGFβ) induced CS upregulation in cardiac fibroblasts. CS accumulation was also observed in both the pressure-overload and the isoprenaline models of pathological remodeling in rats. Early treatment with rhASB in the TAC model, and delayed treatment in the isoprenaline model, proved rhASB to be effective at preventing cardiac deterioration and augmenting functional recovery. Functional improvement was accompanied by reduced myocardial inflammation and overall fibrosis. Tumor necrosis factor α (TNFα) was identified as a direct binding partner of CS GAG chains, and rhASB reduced TNFα-induced inflammatory gene activation in vitro in endothelial cells and macrophages. Conclusions—CS GAGs accumulate during cardiac pathological remodeling, and mediate myocardial inflammation and fibrosis. RhASB targets CS effectively as a novel therapeutic approach for the treatment of heart failure.



Bmal1 in Perivascular Adipose Tissue Regulates Resting Phase Blood Pressure Through Transcriptional Regulation of Angiotensinogen [Original Research Article]

2018-01-25T02:00:26-08:00

Background—The perivascular adipose tissue (PVAT), surrounding vessels, constitutes a distinct functional integral layer of the vasculature required to preserve vascular tone under physiological conditions. However, there is little information regarding the relationship between PVAT and blood pressure regulation, including its potential contributions to circadian blood pressure variation. Methods—Using unique brown adipocyte-specific aryl hydrocarbon receptor nuclear translocator-like protein 1 (Bmal1) and angiotensinogen (Agt) knock out mice we determined the vasoactivity of homogenized PVAT in aortic rings and how brown-adipocyte peripheral expression of Bmal1 and Agt in PVAT regulate the amplitude of diurnal change in blood pressure in mice. Results—We uncovered a peripheral clock in PVAT and demonstrated that loss of Bmal1 in PVAT reduces blood pressure in mice during the resting phase leading to a super-dipper phenotype. PVAT extracts from wild type mice significantly induced contractility of isolated aortic rings in vitro in an endothelium independent manner. This property was impaired in PVAT from brown adipocyte-selective Bmal1 deficient mice (BA-Bmal1-KO). The PVAT contractile properties are mediated by local angiotensin II (Ang II), operating through angiotensin II type 1 receptor-dependent signaling in the isolated vessels and is linked to PVAT circadian regulation of Agt. Indeed, Agt mRNA and Ang II levels in PVAT of BA-Bmal1-KO mice were significantly reduced. Systemic infusion of Ang II, in turn, reduced Bmal1 expression in PVAT while eliminating the hypotensive phenotype during the resting phase in BA-Bmal1-KOmice. Agt, highly expressed in PVAT, shows circadian expression in PVAT and selective deletion of Agt in brown adipocytes recapitulates the phenotype of selective deletion of Bmal1 in brown adipocytes. Furthermore, Agt is a transcriptional target of Bmal1 in PVAT. Conclusions—These data indicate that local Bmal1 in PVAT regulates Agt expression and the ensuing increase in Ang II, which acts on smooth muscle cells (SMCs) in the vessel walls to regulate vasoactivity and blood pressure on a circadian fashion during the resting phase. These findings will contribute to better understand cardiovascular complications of circadian disorders, alterations in the circadian dipping phenotype and the crosstalk between systemic and peripheral regulation of blood pressure.



CD301b/MGL2+ Mononuclear Phagocytes Orchestrate Autoimmune Cardiac Valve Inflammation and Fibrosis [Original Research Article]

2018-01-31T02:00:18-08:00

Background—Valvular heart disease (VHD) is common and affects the mitral valve (MV) most frequently. Despite the prevalence of mitral valve disease (MVD), the cellular and molecular pathways that initiate and perpetuate it are not well understood. Methods—K/B.g7 T cell receptor (TCR) transgenic mice spontaneously develop systemic autoantibody-associated autoimmunity, leading to fully-penetrant fibro-inflammatory MVD and arthritis. We used multiparameter flow cytometry, intracellular cytokine staining, and immunofluorescent staining to characterize the cells in inflamed K/B.g7 MVs. We used genetic approaches to study the contribution of mononuclear phagocytes (MNPs) to MVD in this model. Specifically, we generated K/B.g7 mice in which either CX3CR1 or CD301b/MGL2-expressing MNPs were ablated. Using K/B.g7 mice expressing Cx3Cr1-Cre, we conditionally deleted critical inflammatory molecules from MNPs, including the Fc receptor signal-transducing tyrosine kinase Syk and the cell adhesion molecule very late antigen-4 (VLA-4). We performed complementary studies using monoclonal antibodies to block key inflammatory molecules. We generated bone marrow chimeric mice to define the origin of the inflammatory cells present in the MV and to determine which valve cells respond to the pro-inflammatory cytokine TNF. Finally, we examined specimens from patients with rheumatic heart disease (RHD) to correlate our findings to human pathology.Results—MNPs comprised the vast majority of MV-infiltrating cells; these MNPs expressed CX3CR1 and CD301b/MGL2. Analogous cells were present in human RHD valves. K/B.g7 mice lacking CX3CR1 or in which CD301b/MGL2-expressing MNPs were ablated were protected from MVD. The valve-infiltrating CD301b/MGL2+ MNPs expressed tissue-reparative molecules including arginase-1 (Arg-1) and resistin-like molecule alpha (RELM-α). These MNPs also expressed the pro-inflammatory cytokines TNF and IL-6, and antibody-blockade of these cytokines prevented MVD. Deleting Syk from CX3CR1-expressing MNPs reduced their TNF and IL-6 production and also prevented MVD. TNF acted through TNFR1 expressed on valve-resident cells to increase expression of vascular cell adhesion molecule-1 (VCAM-1). Conditionally deleting the VCAM-1 ligand VLA-4 from CX3CR1-expressing MNPs prevented MVD.Conclusions—CD301b/MGL2+ MNPs are key drivers of autoimmune MVD in K/B.g7 mice and are also present in human RHD. We define key inflammatory molecules that drive MVD in this model, including Syk, TNF, IL-6, VLA-4, and VCAM-1.



Epigenetic Dysregulation of the Drp1 Binding Partners MiD49 and MiD51 Increases Mitotic Mitochondrial Fission and Promotes Pulmonary Arterial Hypertension: Mechanistic and Therapeutic Implications [Original Research Article]

2018-02-05T02:00:21-08:00

Background—Mitotic fission is increased in pulmonary arterial hypertension (PAH), a hyperproliferative, apoptosis-resistant disease. The fission mediator, dynamin related protein 1 (Drp1) must complex with adaptor proteins to cause fission. Drp1-induced fission has been therapeutically targeted in experimental PAH. Here we examine the role of two recently discovered, poorly understood, Drp1 adapter proteins, mitochondrial dynamics protein of 49 and 51 kDa (MiD49 and MiD51) in normal vascular cells and explore their dysregulation in PAH.Methods—Immunoblots of pulmonary artery smooth muscle cells (PASMC, control, n=6; PAH, n=8) and immunohistochemistry of lung sections (control, n=6; PAH, n=6) were used to assess the expression of MiD49 and MiD51. The effects of manipulating MiDs on cell proliferation, cell cycle, and apoptosis were assessed in human and rodent PAH PASMC using flow cytometry. Mitochondrial fission was studied by confocal imaging. A microRNA (miR) involved in the regulation of MiD expression was identified using microarray techniques and in silico analyses. The expression of circulatory miR was assessed using qRT-PCR in healthy volunteers (HV) vs PAH patients from Sheffield, UK (plasma, HV, n=29, PAH, n=27; whole blood, HV, n=11, PAH, n=14), and then confirmed in a cohort from Beijing, China (plasma, HV, n=19, PAH, n=36; whole blood, HV, n=20, PAH, n=39). This work was replicated in monocrotaline and SU5416-hypoxia, preclinical PAH models. siRNA targeting MiDs or a miR mimic were nebulized to rats with monocrotaline-induced PAH (n=4-10).Results—MiD expression is increased in PAH PASMC, which accelerates Drp1-mediated mitotic fission, increases cell proliferation and decreases apoptosis. Silencing MiDs (but not other Drp1 binding partners, Fis1 or MFF) promotes mitochondrial fusion and causes G1-phase cell cycle arrest, through ERK1/2 and CDK4-dependent mechanism. Augmenting MiDs in normal cells causes fission and recapitulates the PAH phenotype. MiD upregulation results from decreased miR-34a-3p expression. Circulatory miR-34a-3p expression is decreased in both PAH patients and in preclinical models of PAH. Silencing MiDs or augmenting miR-34a-3p regresses experimental PAH.Conclusions—In health, MiDs regulate Drp1-mediated fission whilst in disease, epigenetic upregulation of MiDs increases mitotic fission, which drives pathologic proliferation and apoptosis resistance. The miR-34a-3p-MiD pathway offers new therapeutic targets for PAH.



Induction of microRNA-199 by Nitric Oxide in Endothelial Cells is Required for Nitrovasodilator Resistance via Targeting of Prostaglandin I2 Synthase [Original Research Article]

2018-02-05T02:00:21-08:00

Background—Nitrates are widely used to treat coronary artery disease, but their therapeutic value is compromised by nitrate tolerance, owing to the dysfunction of prostaglandin I2 synthase (PTGIS). Micro RNAs (miRNAs) repress target gene expression and are recognized as important epigenetic regulators of endothelial function. The aim of this study was to determine whether nitrates induce nitrovasodilator resistance via microRNA-dependent repression of PTGIS gene expression.Methods—Nitrovasodilator resistance was induced by nitroglycerin (GTN; 100 mg/kg/day, 3 days) infusion in Apoe-/- mice. The responses of aortic arteries to nitric oxide (NO) donors were assessed in organ chamber. The expressional levels of miR-199a/b were assayed by RT-qPCR or FISH.Results—In cultured HUVECs, NO donors induced miR-199a/b endogenous expression of and downregulated PTGIS gene expression, both of which were reversed by carboxyl-PTIO or silence of serum response factor. Evidence from computational and luciferase reporter gene analyses indicates that the seed sequence of 976-982 in 3'-UTR of PTGIS mRNA is a target of miR-199a/b. Gain-functions of miR-199a/b resulting from chemical mimics or adenovirus-mediated overexpression increased PTGIS mRNA degradation in HEK293 cells and HUVECs. Furthermore, GTN-decreased PTGIS gene expression was prevented by miR-199a/b antagomirs or was mirrored by the enforced expression of miR-199a/b in HUVECs. In Apoe-/- mice, GTN induced the ectopic expression of miR-199a/b in the carotid arterial endothelium, decreased PTGIS gene expression, and instigated nitrovasodilator resistance, all of which were abrogated by miR-199a/b antagomirs or LNA-anti-miR-199. Importantly, the effects of miR-199a/b inhibitions were abolished by adenovirus-mediated PTGIS deficiency. Moreover, the enforced expression of miR-199a/b in vivo repressed PTGIS gene expression and impaired the responses of aortic arteries to GTN/sodium nitroprusside/acetylcholine/cinaciguat/riociguat, whereas the exogenous expression of PTGIS gene prevented nitrovasodilator resistance in Apoe-/- mice subjected to GTN infusion or miR-199a/b overexpression. Finally, indomethacin, iloprost, and SQ29548 improved vasorelaxation in GTN-infused Apoe-/- mice, while U51605 induced nitrovasodilator resistance. In humans, the increased expressions of miR-199a/b were closely associated with nitrate tolerance.Conclusions—NO-induced ectopic expression of miR-199a/b in endothelial cells is required for nitrovasodilator resistance via the repression of PTGIS gene expression. Clinically, miR-199a/b is a novel target for the treatment of nitrate tolerance.



The Cardioprotective Role of Myeloid-derived Suppressor Cells in Heart Failure [Original Research Article]

2018-02-01T02:00:20-08:00

Background—Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that expand in cancer, inflammation, and infection and negatively regulate inflammation and the immune response. Heart failure (HF) is a complex clinical syndrome, wherein inflammation induction and incomplete resolution can potentially contribute to HF development and progression. However, the role of MDSCs in HF remains unclear. Methods—The percentage of MDSCs in HF patients and in mice with pressure overload-induced HF using isoproterenol (ISO) infusion or transverse aortic constriction (TAC), was detected by flow cytometry. The effects of MDSCs on ISO- or TAC-induced HF were observed upon depleting MDSCs with 5-fluorouracil (50 mg/kg) or gemcitabine (120 mg/kg), transferring purified MDSCs, or enhancing endogenous MDSCs with rapamycin (2 mg/kg/day). Hypertrophic markers and inflammatory factors were detected by enzyme-linked immunosorbent assay, real-time polymerase chain reaction, or western blot. Cardiac functions were determined by echocardiography and hemodynamic analysis.Results—The percentage of human leukocyte antigen-D-related (HLA-DR)-CD33+CD11b+ MDSCs in the blood of HF patients was significantly increased and positively correlated with the disease severity and increased plasma levels of cytokines, including interleukin (IL)-6, IL-10, and transforming growth factor-β. Furthermore, HF patient-derived MDSCs inhibited T-cell proliferation and interferon-γ secretion. Similar results were observed in TAC- and ISO-induced HF in mice. Importantly, pharmaceutical depletion of MDSCs significantly exacerbated ISO- and TAC-induced pathological cardiac remodeling and inflammation, whereas adoptive transfer of MDSCs prominently rescued ISO- and TAC-induced HF. Consistently, administration of rapamycin significantly increased endogenous MDSCs by suppressing their differentiation and improved ISO- and TAC-induced HF, but MDSC depletion mostly blocked beneficial rapamycin-mediated effects. Mechanistically, MDSC-secreted molecules suppressed ISO-induced hypertrophy and proinflammatory genes expression in cardiomyocytes in a co-culture system. Neutralization of IL-10 blunted both monocytic MDSC (M-MDSC)- and granulocytic MDSC (G-MDSC)-mediated anti-inflammatory and antihypertrophic effects, but treatment with a nitric oxide (NO) inhibitor only partially blocked the antihypertrophic effect of M-MDSCs.Conclusions—Our findings revealed a cardioprotective role of MDSCs in HF by their antihypertrophic effects on cardiomyocytes and anti-inflammatory effects through IL-10 and NO. Pharmacological targeting of MDSCs by rapamycin constitutes a promising therapeutic strategy for HF.



Transplant-Free Survival and Interventions at 6 Years in the Single Ventricle Reconstruction Trial [Original Research Article]

2018-02-01T02:00:23-08:00

Background—In the Single Ventricle Reconstruction (SVR) trial, one-year transplant-free survival was better for the Norwood procedure with right ventricle-to-pulmonary artery shunt (RVPAS) compared with a modified Blalock-Taussig shunt (MBTS) in patients with hypoplastic left heart and related syndromes. At 6 years, we compared transplant-free survival and other outcomes between the groups. Methods—Medical history was collected annually using medical record review, telephone interviews, and the death index. The cohort included 549 patients randomized and treated in the SVR trial. Results—Transplant-free survival for the RVPAS vs. MBTS groups did not differ at 6 years (64% vs. 59%, P=0.25) or with all available follow-up of 7.1±1.6 years (log-rank P=0.13). The RVPAS vs. MBTS treatment effect had non-proportional hazards (P=0.009); the hazard ratio (HR) for death or transplant favored the RVPAS before Stage II surgery (HR=0.66; 95% CI 0.48-0.92). The effect of shunt type on death or transplant was not statistically significant between Stage II to Fontan surgery (HR 1.36, 95% CI 0.86-2.17, p=0.17) or after the Fontan procedure (HR 0.76, 95% CI 0.33-1.74, p=0.52). By 6 years, RVPAS patients had a higher incidence of catheter interventions (0.38 vs. 0.23/patient-year, P<0.001), primarily due to more interventions between the Stage II and Fontan procedures (HR=1.72, 95% CI 1.00-3.03). Complications did not differ by shunt type; by 6 years, one in five patients had had a thrombotic event and one in six, seizures.Conclusions—By 6 years, the hazards of death or transplant and catheter interventions were not different between the RVPAS vs. MBTS groups. Children assigned to the RVPAS group had 5% higher transplant-free survival but the difference did not reach statistical significance, and they required more catheter interventions. Both treatment groups have accrued important complications. Clinical Trial Registration—Unique Identifier: NCT00115934 URL: http://clinicaltrials.gov



NMDA-Type Glutamate Receptor Activation Promotes Vascular Remodeling and Pulmonary Arterial Hypertension [Original Research Article]

2018-02-14T02:00:28-08:00

Background—Excessive proliferation and apoptosis resistance in pulmonary vascular cells underlie vascular remodeling in pulmonary arterial hypertension (PAH). Specific treatments for PAH exist, mostly targeting endothelial dysfunction, but high pulmonary arterial pressure still causes heart failure and death. Pulmonary vascular remodeling may be driven by metabolic reprogramming of vascular cells to increase glutaminolysis and glutamate production. The N-methyl-D-aspartate receptor (NMDAR), a major neuronal glutamate receptor, is also expressed on vascular cells, but its role in PAH is unknown.Methods—We assessed the status of the glutamate-NMDAR axis in the pulmonary arteries of PAH patients and controls, through mass spectrometry imaging, western blotting and immunohistochemistry. We measured the glutamate release from cultured pulmonary vascular cells using enzymatic assays, and analyzed NMDAR regulation/phosphorylation through western blot experiments. The effect of NMDAR blockade on human pulmonary arterial smooth muscle cell (hPASMC) proliferation was determined using a BrdU incorporation assay. We assessed the role of NMDARs in vascular remodeling associated to pulmonary hypertension (PH), both in smooth muscle-specific NMDAR knockout mice exposed to chronic hypoxia and in the monocrotaline rat model of PH using NMDAR blockers.Results—We report glutamate accumulation, upregulation of the NMDAR, and NMDAR engagement reflected by increases in GluN1-subunit phosphorylation, in the pulmonary arteries of human PAH patients. Kv channel inhibition and ETAR activation amplified calcium-dependent glutamate release from hPASMCs, and ETAR and PDGFR activation led to NMDAR engagement, highlighting crosstalk between the glutamate-NMDAR axis and major PAH-associated pathways. The PDGF-BB-induced proliferation of hPASMCs involved NMDAR activation and phosphorylated GluN1 subunit localization to cell-cell contacts, consistent with glutamatergic communication between proliferating hPASMCs via NMDARs. Smooth-muscle NMDAR deficiency in mice attenuated the vascular remodeling triggered by chronic hypoxia, highlighting the role of vascular NMDARs in PH. Pharmacological NMDAR blockade in the monocrotaline rat model of PH had beneficial effects on cardiac and vascular remodeling, decreasing endothelial dysfunction, cell proliferation and apoptosis resistance, while disrupting the glutamate-NMDAR pathway in pulmonary arteries.Conclusions—These results reveal a dysregulation of the glutamate-NMDAR axis in the pulmonary arteries of PAH patients, and identify vascular NMDARs as targets for anti-remodeling treatments in PAH.






Randomized Comparisons of Double-Dose Clopidogrel or Adjunctive Cilostazol versus Standard Dual Anti-platelet in Patients with High Post-Treatment Platelet Reactivity: Results of the CREATIVE Trial (Clopidogrel Response Evaluation and AnTi-platelet InterVEntion in High Thrombotic Risk PCI Patients) [Original Research Article]

2018-02-02T02:00:24-08:00

Background—Patients undergoing percutaneous coronary intervention (PCI) react differently to antiplatelet drugs. Those with low responsiveness to clopidogrel have a higher risk of cardiac ischemic events. The goal of this study is to conduct a head-to-head comparison of the safety and effectiveness of intensified antiplatelet therapies (either double-dose clopidogrel [DOUBLE] or adjunctive cilostazol [TRIPLE]) and conventional strategy (STANDARD) in post-PCI patients.Methods—In this single-center, randomized, controlled trial, we used thromboelastography (TEG), a platelet function test, to select 1078 PCI patients at high thrombotic risk and compared the intensified antiplatelet therapies with standard antiplatelet therapy. The primary outcome was the incidence of major adverse cardiac and cerebrovascular events at 18 months post-PCI, defined as a composite of all-cause death, myocardial infarction, target vessel revascularization or stroke. Bleeding Academic Research Consortium (BARC) defined bleeding complications (types 1, 2, 3, or 5) were the safety endpoints.Results—The primary endpoint occurred in 52 patients (14.4%) in STANDARD group, 38 patients (10.6%) in DOUBLE group and 30 patients (8.5%) in TRIPLE group (HR: 0.720, 95%CI: 0.474-1.094, DOUBLE vs. STANDARD; HR: 0.550, 95%CI: 0.349-0.866, TRIPLE vs. STANDARD). No significant difference in the rates of major bleeding (BARC grade≥3) was found in DOUBLE group (3.34% vs. 1.93% in STANDARD, P=0.133) and TRIPLE group (2.53% vs 1.93% in STANDARD, P=0.240). The rate of BARC-defined minor bleeding increased in DOUBLE group (27.4% vs. 20.3% in STANDARD, P=0.031), but not in TRIPLE group (23.6% vs. 20.3% in STANDARD, P=0.146). Conclusions—In patients with low responsiveness to clopidogrel, as measured by thromboelastography, the intensified antiplatelet strategies with adjunctive use of cilostazol significantly improved the clinical outcomes without increasing the risk of major bleeding. Decreased trend of negative outcomes could be observed in patients with double dosage of clopidogrel, but the difference was not significant.Clinical Trial Registration—URL: http://www.clinicaltrials.gov Unique Identifier: NCT01779401.



Nicotinamide Riboside Preserves Cardiac Function in a Mouse Model of Dilated Cardiomyopathy [Original Research Article]

2017-12-07T01:55:18-08:00

Background—Myocardial metabolic impairment is a major feature in chronic heart failure (HF). As the major coenzyme in fuel oxidation and oxidative phosphorylation and a substrate for enzymes signaling energy stress and oxidative stress response, NAD+ is emerging as a metabolic target in a number of diseases including HF. Little is known on mechanisms regulating homeostasis of NAD+ in the failing heart.Methods—To explore possible alterations of NAD+ homeostasis in the failing heart, we quantified expression of NAD+ biosynthetic enzymes in human failing heart and in the heart of a mouse model of dilated cardiomyopathy (DCM) triggered by SRF transcription factor depletion in the heart (SRFHKO) or of cardiac hypertrophy triggered by transverse aorta constriction (TAC). We studied the impact of NAD+ precursor supplementation on cardiac function in both mouse models.Results—We observed a 30% loss in levels of NAD+ in the murine failing heart of both DCM and TAC mice that was accompanied by a decrease in expression of the NAMPT enzyme that recycles the nicotinamide (NAM) precursor whereas the nicotinamide riboside kinase 2 (NMRK2) that phosphorylates the nicotinamide riboside (NR) precursor is increased, to a higher level in the DCM (40 fold) than in TAC (4 fold). This shift was also observed in human failing heart biopsies compared to non-failing controls. We show that the Nmrk2 gene is an AMPK and PPARalpha responsive gene that is activated by energy stress and NAD+ depletion in isolated rat cardiomyocytes. NR efficiently rescues NAD+ synthesis in response to FK866-mediated inhibition of NAMPT and stimulates glycolysis in cardiomyocytes. Accordingly, we show that NR supplementation in food attenuates the development of HF in mice, more robustly in DCM, and partially after TAC, by stabilizing myocardial NAD+ levels in the failing heart. NR treatment also robustly increases the myocardial levels of three metabolites, nicotinic acid adenine dinucleotide, methyl-NAM and N1-Methyl-4-pyridone-5-carboxamide, which can be used as validation biomarkers for the treatment.Conclusions—The data show that nicotinamide riboside, the most energy-efficient among NAD precursors, could be useful for treatment of HF notably in the context of DCM, a disease with few therapeutic options.



Single-Cell Sequencing of the Healthy and Diseased Heart Reveals Ckap4 as a New Modulator of Fibroblasts Activation [Original Research Article]

2018-01-31T02:00:20-08:00

Background—Genome-wide transcriptome analysis has greatly advanced our understanding of the regulatory networks underlying basic cardiac biology and mechanisms driving disease. However, so far, the resolution of studying gene expression patterns in the adult heart has been limited to the level of extracts from whole tissues. The use of tissue homogenates inherently causes the loss of any information on cellular origin or cell type-specific changes in gene expression. Recent developments in RNA amplification strategies provide a unique opportunity to use small amounts of input RNA for genome-wide sequencing of single cells.Methods—Here, we present a method to obtain high quality RNA from digested cardiac tissue from adult mice for automated single-cell sequencing of both the healthy and diseased heart.Results—After optimization, we were able to perform single-cell sequencing on adult cardiac tissue under both homeostatic conditions and after ischemic injury. Clustering analysis based on differential gene expression unveiled known and novel markers of all main cardiac cell types. Based on differential gene expression we were also able to identify multiple subpopulations within a certain cell type. Furthermore, applying single-cell sequencing on both the healthy and the injured heart indicated the presence of disease-specific cell subpopulations. As such, we identified cytoskeleton associated protein 4 (Ckap4) as a novel marker for activated fibroblasts that positively correlates with known myofibroblast markers in both mouse and human cardiac tissue. Ckap4 inhibition in activated fibroblasts treated with TGFβ triggered a greater increase in the expression of genes related to activated fibroblasts compared to control, suggesting a role of Ckap4 in modulating fibroblast activation in the injured heart.Conclusions—Single-cell sequencing on both the healthy and diseased adult heart allows us to study transcriptomic differences between cardiac cells, as well as cell type-specific changes in gene expression during cardiac disease. This new approach provides a wealth of novel insights into molecular changes that underlie the cellular processes relevant for cardiac biology and pathophysiology. Applying this technology could lead to the discovery of new therapeutic targets relevant for heart disease.



Effect of Distinct Lifestyle Interventions on Mobilization of Fat Storage Pools: The CENTRAL MRI Randomized Controlled Trial [Original Research Article]

2017-11-15T02:00:23-08:00

Background—We aimed to assess whether distinct lifestyle strategies can differentially affect specific body adipose depots.Methods—We performed an eighteen-month randomized controlled trial among 278 sedentary adults with abdominal obesity (75%) or dyslipidemia in an isolated workplace with a monitored provided lunch. Participants were randomized to iso-caloric low-fat (LF) or Mediterranean/low-carbohydrate (MED/LC) diet+28g walnuts/day with/without added moderate physical activity (PA;80% aerobic; supervised/free gym membership). Overall primary outcome was body fat re-distribution, and the main specific endpoint was visceral adipose tissue (VAT). We further followed the dynamics of different fat depots [deep/superficial subcutaneous (D/SSAT), liver, pericardial, muscle, pancreas and renal-sinus] by magnetic-resonance-imaging.Results—Of 278 participants (age=48y; 89%men, body-mass-index=30.8kg/m2), 86% completed the trial, with good adherence. The LF group preferentially decreased reported fat intake (-21.0% vs. -11.5% for the MED/LC; P<0.001), and the MED/LC group decreased reported carbohydrates intake (-39.5%vs. -21.3% for the LF;P<0.001). The PA+ groups significantly increased the metabolic-equivalents (METs)/week vs. the PA- groups (19.0 vs. 2.1;P=0.009). Whereas final moderate weight loss was indifferent, exercise attenuated the waist circumference rebound with the greatest effect in MED/LCPA+ group (P<0.05). VAT (-22%), intra-hepatic (-29%), and Intra-pericardial (-11%) fats declines were higher than pancreatic and femur intermuscular fats (1-2%) loss. Independent of weight loss, PA+ with either diet had a significantly greater effect on decreasing VAT [mean-of-difference=-6.67cm2;95%CI:(-14.8 to -0.45) compared with PA-]. The MED/LC diet was superior to LF in decreasing intra-hepatic, intra-pericardial and pancreatic fats (P<0.05 for all). In contrast, renal-sinus and femoral-intermuscular fats were not differentially altered by lifestyle interventions, but by weight loss per-se. In multivariate models, further adjusted for weight loss, losing VAT or intra-hepatic fat were independently associated with improved lipid profile, losing deep-SAT with improved insulin sensitivity and losing superficial-SAT remained neutral except of association with decreased leptin.Conclusions—Moderate weight loss alone inadequately reflects the significant lifestyle effects on atherogenic and diabetogenic fat depots. The MED/LC diet mobilizes specific ectopic fat depots, and exercise has an independent contribution to VAT loss. Fat depots exhibit diverse responsiveness and are differentially related to cardiometabolic markers. Distinct lifestyle protocols may uniquely induce fat mobilization from specific anatomical sites.Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01530724.



Cardiovascular Risk Prediction Functions Underestimate Risk in HIV Infection [Original Research Article]

2018-02-14T02:00:25-08:00

Background—Cardiovascular disease (CVD) risk is elevated in HIV-infected individuals, with contributions from both traditional and non-traditional risk factors. The accuracy of established CVD risk prediction functions in HIV is uncertain. We sought to assess the performance of three established CVD risk prediction functions in a longitudinal cohort of HIV-infected men.Methods—Framingham Heart Study (Framingham) functions for hard coronary heart disease (Framingham CHD) and atherosclerotic CVD (Framingham ASCVD) and the American College of Cardiology/American Heart Association (ACC/AHA ASCVD) function were applied to the Partners HIV cohort. Risk scores were calculated between 1/1/2006 and 12/31/2008. Outcomes included CHD (myocardial infarction [MI] or coronary death) for the Framingham CHD function and ASCVD (MI, stroke or coronary death) for the Framingham ASCVD and ACC/AHA ASCVD functions. We investigated the accuracy of CVD risk prediction for each function when applied to the HIV cohort using comparison of Cox regression coefficients, discrimination, and calibration.Results—The HIV cohort was comprised of 1280 men followed for a median of 4.4 years. There were 80 (6.3%) ASCVD events; 5-year incidence rate was 16.7 per 1000 person years. Discrimination was moderate to poor as indicated by low c statistic (0.68 for Framingham CHD, 0.65 for ACC/AHA, and 0.67 for Framingham ASCVD). Observed CVD risk exceeded predicted risk for each of the functions in most deciles of predicted risk. Calibration, or goodness-of-fit of the models, was consistently poor, with significant chi-square p values for all functions. Recalibration did not significantly improve model fit.Conclusions—Cardiovascular risk prediction functions developed for use in the general population are inaccurate in HIV infection and systematically underestimate risk in a cohort of HIV-infected men. Development of tailored CVD risk prediction functions incorporating traditional CVD risk factors and HIV-specific factors is likely to result in more accurate risk estimation to guide preventative CVD care.



A Novel Adipokine, FAM19A5, Inhibits Postinjury Neointima Formation through Sphingosine-1-Phosphate Receptor 2 [Original Research Article]

2018-02-16T02:00:25-08:00

Background—Obesity plays crucial roles in the development of cardiovascular diseases (CVDs). However, the mechanisms that link obesity and CVDs remain elusive. Compelling evidence indicates that adipokines play an important role in obesity-related CVDs. Here, we found a new adipokine named family with sequence similarity 19, member A5 (FAM19A5), a protein with unknown function that was predicted to be distantly related to the CC-chemokine family. We aimed to test whether adipose-derived FAM19A5 regulates vascular pathology upon injury. Methods—DNA cloning, protein expression, purification, and N-terminal sequencing were applied to characterize FAM19A5. Adenovirus infection and siRNA transfection were performed to regulate FAM19A5 expression. Balloon and wire injury were performed in vivo on the rat carotid arteries and mouse femoral arteries, respectively. Bioinformatics analysis, radioactive ligand-receptor binding assays, receptor internalization, and calcium mobilization assays were used to identify the functional receptor for FAM19A5.Results—We firstly characterized FAM19A5 as a secreted protein, and the first 43 N-terminal amino acids were the signal peptides. Both FAM19A5 mRNA and protein were abundantly expressed in the adipose tissue, but were downregulated in obese mice. Overexpression of FAM19A5 markedly inhibited vascular smooth muscle cell (VSMC) proliferation and migration and neointima formation in the carotid arteries of balloon-injured rats. Accordingly, FAM19A5 silencing in adipocytes significantly promoted VSMC activation. Adipose-specific FAM19A5 transgenic mice showed greater attenuation of neointima formation compared to wild-type littermates fed with or without western-style diet. We further revealed that sphingosine-1-phosphate receptor 2 (S1PR2) was the functional receptor for FAM19A5, with a dissociation constant (Kd) of 0.634 nM. Inhibition of S1PR2 or its downstream G12/13-RhoA signaling circumvented the suppressive effects of FAM19A5 on VSMC proliferation and migration.Conclusions—We revealed that a novel adipokine, FAM19A5, was capable of inhibiting postinjury neointima formation via S1PR2-G12/13-RhoA signaling. Downregulation of FAM19A5 during obesity may trigger cardiometabolic diseases.



Cytosolic DNA Sensing Promotes Macrophage Transformation and Governs Myocardial Ischemic Injury [Original Research Article]

2018-02-01T02:00:24-08:00

Background—Myocardium irreversibly injured by ischemic stress must be efficiently repaired to maintain tissue integrity and contractile performance. Macrophages play critical roles in this process. These cells transform across a spectrum of phenotypes to accomplish diverse functions ranging from mediating the initial inflammatory responses that clear damaged tissue to subsequent reparative functions that help rebuild replacement tissue. Although macrophage transformation is crucial to myocardial repair, events governing this transformation are poorly understood. Methods—Here, we set out to determine whether innate immune responses triggered by cytoplasmic DNA play a role. Results—We report that ischemic myocardial injury, and the resulting release of nucleic acids, activates the recently described cGAS (GMP-AMP synthase)-STING (stimulator of interferon genes) pathway. Animals lacking cGAS display significantly improved early survival post-MI, diminished pathological remodeling including ventricular rupture, enhanced angiogenesis, and preserved ventricular contractile function. Furthermore, cGAS loss-of-function abolishes the induction of key inflammatory programs such as iNOS and promotes the transformation of macrophages to a reparative phenotype, which results in enhanced repair and improved hemodynamic performance.Conclusions—These results reveal, for the first time, that the cytosolic DNA receptor cGAS functions during cardiac ischemia as a pattern recognition receptor in the sterile immune response. Further, we report that this pathway governs macrophage transformation, thereby regulating post-injury cardiac repair. As modulators of this pathway are currently in clinical use, our findings raise the prospect of new treatment options to combat ischemic heart disease and its progression to heart failure.



Reversing the Cardiac Effects of Sedentary Aging in Middle Age—A Randomized Controlled Trial: Implications For Heart Failure Prevention [Original Research Article]

2018-01-08T01:55:20-08:00

Background— Poor fitness in middle age is a risk factor for heart failure, particularly heart failure with a preserved ejection fraction. The development of heart failure with a preserved ejection fraction is likely mediated through increased left ventricular (LV) stiffness, a consequence of sedentary aging. In a prospective, parallel group, randomized controlled trial, we examined the effect of 2 years of supervised highintensity exercise training on LV stiffness.Methods— Sixty-one (48% male) healthy, sedentary, middle-aged participants (53±5 years) were randomly assigned to either 2 years of exercise training (n=34) or attention control (control; n=27). Right heart catheterization and 3-dimensional echocardiography were performed with preload manipulations to define LV end-diastolic pressure-volume relationships and Frank-Starling curves. LV stiffness was calculated by curve fit of the diastolic pressure-volume curve. Maximal oxygen uptake (Vo2max) was measured to quantify changes in fitness.Results— Fifty-three participants completed the study. Adherence to prescribed exercise sessions was 88±11%. Vo2max increased by 18% (exercise training: pre 29.0±4.8 to post 34.4±6.4; control: pre 29.5±5.3 to post 28.7±5.4, group×time P<0.001) and LV stiffness was reduced (right/downward shift in the end-diastolic pressure-volume relationships; preexercise training stiffness constant 0.072±0.037 to postexercise training 0.051±0.0268, P=0.0018), whereas there was no change in controls (group×time P<0.001; pre stiffness constant 0.0635±0.026 to post 0.062±0.031, P=0.83). Exercise increased LV end-diastolic volume (group×time P<0.001), whereas pulmonary capillary wedge pressure was unchanged, providing greater stroke volume for any given filling pressure (loading×group×time P=0.007).Conclusions— In previously sedentary healthy middle-aged adults, 2 years of exercise training improved maximal oxygen uptake and decreased cardiac stiffness. Regular exercise training may provide protection against the future risk of heart failure with a preserved ejection fraction by preventing the increase in cardiac stiffness attributable to sedentary aging.Clinical Trial Registration— URL: https://clinicaltrials.gov. Unique identifier: NCT02039154.



Perioperative Myocardial Injury After Noncardiac Surgery: Incidence, Mortality, and Characterization [Original Research Article]

2017-12-04T01:55:19-08:00

Background—Perioperative myocardial injury (PMI) seems to be a contributor to mortality after noncardiac surgery. Because the vast majority of PMIs are asymptomatic, PMI usually is missed in the absence of systematic screening.Methods—We performed a prospective diagnostic study enrolling consecutive patients undergoing noncardiac surgery who had a planned postoperative stay of ≥24 hours and were considered at increased cardiovascular risk. All patients received a systematic screening using serial measurements of high-sensitivity cardiac troponin T in clinical routine. PMI was defined as an absolute high-sensitivity cardiac troponin T increase of ≥14 ng/L from preoperative to postoperative measurements. Furthermore, mortality was compared among patients with PMI not fulfilling additional criteria (ischemic symptoms, new ECG changes, or imaging evidence of loss of viable myocardium) required for the diagnosis of spontaneous acute myocardial infarction versus those that did.Results—From 2014 to 2015 we included 2018 consecutive patients undergoing 2546 surgeries. Patients had a median age of 74 years and 42% were women. PMI occurred after 397 of 2546 surgeries (16%; 95% confidence interval, 14%-17%) and was accompanied by typical chest pain in 24 of 397 patients (6%) and any ischemic symptoms in 72 of 397 (18%). Crude 30-day mortality was 8.9% (95% confidence interval [CI], 5.7-12.0) in patients with PMI versus 1.5% (95% CI, 0.9-2.0) in patients without PMI (P<0.001). Multivariable regression analysis showed an adjusted hazard ratio of 2.7 (95% CI, 1.5-4.8) for 30-day mortality. The difference was retained at 1 year with mortality rates of 22.5% (95% CI, 17.6-27.4) versus 9.3% (95% CI, 7.9-10.7). Thirty-day mortality was comparable among patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction (280/397, 71%) versus those with at least 1 additional criterion (10.4%; 95% CI, 6.7-15.7, versus 8.7%; 95% CI, 4.2-16.7; P=0.684).Conclusions—PMI is a common complication after noncardiac surgery and, despite early detection during routine clinical screening, is associated with substantial short- and long-term mortality. Mortality seems comparable in patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction versus those patients who do.Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT02573532.



Persistent Long-Term Structural, Functional, and Metabolic Changes After Stress-Induced (Takotsubo) Cardiomyopathy [Original Research Article]

2017-11-11T14:50:20-08:00

BACKGROUND: Takotsubo cardiomyopathy is an increasingly recognized acute heart failure syndrome precipitated by intense emotional stress. Although there is an apparent rapid and spontaneous recovery of left ventricular ejection fraction, the long-term clinical and functional consequences of takotsubo cardiomyopathy are ill-defined.METHODS: In an observational case-control study, we recruited 37 patients with prior (>12-month) takotsubo cardiomyopathy, and 37 age-, sex-, and comorbidity-matched control subjects. Patients completed the Minnesota Living with Heart Failure Questionnaire. All participants underwent detailed clinical phenotypic characterization, including serum biomarker analysis, cardiopulmonary exercise testing, echocardiography, and cardiac magnetic resonance including cardiac 31P-spectroscopy.RESULTS: Participants were predominantly middle-age (64±11 years) women (97%). Although takotsubo cardiomyopathy occurred 20 (range 13-39) months before the study, the majority (88%) of patients had persisting symptoms compatible with heart failure (median of 13 [range 0-76] in the Minnesota Living with Heart Failure Questionnaire) and cardiac limitation on exercise testing (reduced peak oxygen consumption, 24±1.3 versus 31±1.3 mL/kg/min, P<0.001; increased VE/VCO2 slope, 31±1 versus 26±1, P=0.002). Despite normal left ventricular ejection fraction and serum biomarkers, patients with prior takotsubo cardiomyopathy had impaired cardiac deformation indices (reduced apical circumferential strain, ‒16±1.0 versus ‒23±1.5%, P<0.001; global longitudinal strain, ‒17±1 versus ‒20±1%, P=0.006), increased native T1 mapping values (1264±10 versus 1184±10 ms, P<0.001), and impaired cardiac energetic status (phosphocreatine/γ-adenosine triphosphate ratio, 1.3±0.1 versus 1.9±0.1, P<0.001).CONCLUSIONS: In contrast to previous perceptions, takotsubo cardiomyopathy has long-lasting clinical consequences, including demonstrable symptomatic and functional impairment associated with persistent subclinical cardiac dysfunction. Taken together our findings demonstrate that after takotsubo cardiomyopathy, patients develop a persistent, long-term heart failure phenotype.CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT02989454.



Worsening Renal Function in Acute Heart Failure Patients Undergoing Aggressive Diuresis is Not Associated with Tubular Injury [Original Research Article]

2018-01-19T02:00:17-08:00

Background—Worsening renal function (WRF) in the setting of aggressive diuresis for acute heart failure (AHF) treatment may reflect renal tubular injury or simply indicate a hemodynamic or functional change in glomerular filtration. Well-validated tubular injury biomarkers—NAG, NGAL, and KIM-1— are now available that can quantify the degree of renal tubularinjury. The ROSE-AHF trial provides an experimental platform for the study of mechanisms of WRF during aggressive diuresis for AHF, as the ROSE-AHF protocol dictated high dose loop diuretic therapy in all patients. We sought to determine whether tubular injury biomarkers are associated with WRF in the setting of aggressive diuresis and its association with prognosis.Methods—Patients in the multicenter ROSE-AHF trial with baseline and 72-hour urine tubular injury biomarkers were analyzed (N=283). WRF was defined as a ≥20% decrease in glomerular filtration rate estimated using cystatin C.Results—Consistent with protocol driven aggressive dosing of loop diuretics, participants received a median 560 mg of IV furosemide equivalents (IQR 300-815 mg) which induced a urine output of 8425 mL (IQR 6341-10528 ml) over the 72-hour intervention period. Levels of NAG and KIM-1 did not change with aggressive diuresis (P>0.59, both), whereas levels of NGAL decreased slightly [-8.7 ng/mg (-169, 35 ng/mg), P<0.001]. WRF occurred in 21.2% of the population and was not associated with an increase in any marker of renal tubular injury: NGAL (P=0.21), NAG (P=0.46), or KIM-1 (P=0.22). Increases in NGAL, NAG, and KIM-1 were paradoxically associated with improved survival (adjusted HR: 0.80 per 10 percentile increase, 95% CI: 0.69-0.91; P=0.001). Conclusions—Kidney tubular injury does not appear to have an association with WRF in the context of aggressive diuresis of AHF patients. These findings reinforce the notion that the small to moderate deteriorations in renal function commonly encountered with aggressive diuresis are dissimilar from traditional causes of acute kidney injury.



Effects of Bariatric Surgery in Obese Patients With Hypertension: The GATEWAY Randomized Trial (Gastric Bypass to Treat Obese Patients With Steady Hypertension) [Original Research Article]

2017-11-13T10:35:19-08:00

BACKGROUND: Recent research efforts on bariatric surgery have focused on metabolic and diabetes mellitus resolution. Randomized trials designed to assess the impact of bariatric surgery in patients with obesity and hypertension are needed.METHODS: In this randomized, single-center, nonblinded trial, we included patients with hypertension (using ≥2 medications at maximum doses or >2 at moderate doses) and a body mass index between 30.0 and 39.9 kg/m2. Patients were randomized to Roux-en-Y gastric bypass plus medical therapy or medical therapy alone. The primary end point was reduction of ≥30% of the total number of antihypertensive medications while maintaining systolic and diastolic blood pressure <140 mm Hg and 90 mm Hg, respectively, at 12 months.RESULTS: We included 100 patients (70% female, mean age 43.8±9.2 years, mean body mass index 36.9±2.7 kg/m2), and 96% completed follow-up. Reduction of ≥30% of the total number of antihypertensive medications while maintaining controlled blood pressure occurred in 41 of 49 patients from the gastric bypass group (83.7%) compared with 6 of 47 patients (12.8%) from the control group with a rate ratio of 6.6 (95% confidence interval, 3.1-14.0; P<0.001). Remission of hypertension was present in 25 of 49 (51%) and 22 of 48 (45.8%) patients randomized to gastric bypass, considering office and 24-hour ambulatory blood pressure monitoring, respectively, whereas no patient submitted to medical therapy was free of antihypertensive drugs at 12 months. A post hoc analysis for the primary end point considering the SPRINT (Systolic Blood Pressure Intervention Trial) target reached consistent results, with a rate ratio of 3.8 (95% confidence interval, 1.4-10.6; P=0.005). Eleven patients (22.4%) from the gastric bypass group and none in the control group were able to achieve SPRINT levels without antihypertensives. Waist circumference, body mass index, fasting plasma glucose, glycohemoglobin, low-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein, and 10-year Framingham risk score were lower in the gastric bypass than in the control group.CONCLUSIONS: Bariatric surgery represents an effective strategy for blood pressure control in a broad population of patients with obesity and hypertension.CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT01784848.



Hospital Variation in Adherence Rates to Secondary Prevention Medications and the Implications on Quality [Original Research Article]

2018-01-31T02:00:23-08:00

Background—Medication adherence is important to improve long-term outcomes after acute myocardial infarction (MI). We hypothesized that there is significant variation among United States (U.S.) hospitals in terms of post-MI medication adherence, and that patients treated at hospitals with higher post-MI medication adherence will have better long-term cardiovascular outcomes. Methods—We identified 19,704 Medicare patients discharged after acute MI from 347 U.S. hospitals participating in the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With The Guidelines (ACTION Registry-GWTG) from 1/2/2007 to 10/1/2010. Using linked Medicare Part D prescription filling data, medication adherence was defined as proportion of days covered (PDC) >80% within 90 days post-discharge. Cox proportional hazards modeling was used to compare 2-year major adverse cardiovascular events (MACE) among hospitals with high, moderate, and low 90-day medication adherence. Results—By 90 days post-MI, overall rates of adherence to medications prescribed at discharge were 68% for beta-blockers, 63% for statins, 64% for angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs), and 72% for thienopyridines. Adherence to these medications up to 90 days varied significantly among hospitals: beta-blockers (PDC >80%; 59-75%), statins (55-69%), thienopyridines (64-77%), and ACEIs/ARBs (57-69%). Compared with hospitals in the lowest quartile of 90-day composite medication adherence, hospitals with the highest adherence had lower unadjusted and adjusted 2-year MACE risk (27.5% vs. 35.3%, adjusted hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.80-0.96). High adherence hospitals also had lower adjusted rates of death or readmission (HR 0.90, 95% CI 0.85-0.96), while there was no difference in mortality after adjustment.Conclusions—Post-discharge use of secondary prevention medications vary significantly among U.S. hospitals and are inversely associated with two-year outcomes. Hospitals may improve post-discharge medication adherence and patient outcomes through better coordination of care between inpatient and outpatient settings.



Mortality Differences Associated with Treatment Responses in CANTOS and FOURIER: Insights and Implications [Perspective]

2017-12-22T02:00:22-08:00

Similarities and differences in two contemporary post-randomization on-treatment analyses from the FOURIER and CANTOS trials may provide insight into what factors drive reductions in cardiovascular mortality and all-cause mortality among atherosclerosis patients already treated with high intensity statins. In the first paper, the FOURIER investigators elegantly demonstrate that lower is better for low-density lipoprotein cholesterol (LDLC) after adjunctive therapy with the PCSK9 inhibitor evolocumab1. For the FOURIER primary endpoint (a composite of myocardial infarction, stroke, coronary revascularization, unstable angina, or cardiovascular death), there was a highly significant monotonic relationship between sequentially lower achieved LDLC concentrations and lower cardiovascular risk, extending even to those with on-treatment LDLC below 20 mg/dL. This benefit was largely driven by statistically significant reductions in the trial composite endpoint among those with LDLC levels below the approximate on-treatment median of 50mg/dL (where hazard ratios ranged between 0.76 and 0.85). By contrast, marginal and non-significant reductions were observed among those in FOURIER with on-treatment LDLC levels above 50mg/dL (where hazard ratios ranged from 0.94 to 0.97). These PCSK9 data are important since evolocumab has powerful effects on LDLC, but no effect on high-sensitivity C-reactive protein (hsCRP).



Benefit of Adding Ezetimibe to Statin Therapy on Cardiovascular Outcomes and Safety in Patients With vs. Without Diabetes: Results from IMPROVE-IT [Original Research Article]

2017-12-20T02:00:22-08:00

Background—Ezetimibe, when added to simvastatin, reduces cardiovascular events following acute coronary syndrome (ACS); we explored outcomes stratified by diabetes mellitus (DM).Methods—In IMPROVE-IT, 18,144 patients post ACS with LDL-C 50-125 mg/dL were randomized to ezetimibe/simvastatin-40mg (E/S) or placebo/simvastatin-40mg (P/S). The primary composite endpoint was cardiovascular death, major coronary events, and stroke. DM was a prespecified subgroup.Results—The 4933 (27%) patients with DM were more often older, female, with prior MI and revascularization, and presented more frequently with non-ST segment elevation ACS compared to non-DM (each p<0.001). The median admission LDL-C was lower among patients with DM (89 vs. 97 mg/dL, p<0.001). E/S achieved a significantly lower median time-weighted average LDL-C compared to P/S, irrespective of DM (DM: 49 vs. 67 mg/dL; No DM: 55 vs. 71 mg/dL, both P<0.001). In DM patients, E/S reduced the 7-year Kaplan-Meier primary endpoint event rate by 5.5% absolute (HR 0.85; 95% CI, 0.78-0.94); in non-DM patients the absolute difference was 0.7% (HR 0.98; 95% CI, 0.91-1.04; Pinteraction=0.02). The largest relative reductions in DM patients were in MI (24%) and ischemic stroke (39%). No differences in safety outcomes by treatment were present regardless of DM. When stratified further by age, patients ≥75 years had a 20% relative reduction in the primary endpoint regardless of DM (Pinteraction=0.91), while patients <75 years with DM had greater benefit than those without (Pinteraction=0.011). When stratified by the TIMI risk score for Secondary Prevention, all patients with DM demonstrated benefit with E/S regardless of risk. In contrast, among non-diabetics, patients with a high risk score experienced a significant 18% relative reduction in the composite of cardiovascular death, MI, and ischemic stroke with E/S compared to P/S, whereas non-diabetics at low or moderate risk demonstrated no benefit with the addition of ezetimibe to simvastatin (Pinteraction 0.034).Conclusions—In IMPROVE-IT the benefit of adding ezetimibe to statin was enhanced in patients with DM and in high-risk non-diabetics. Clinical Trial Registration—URL: https://clinicaltrials.gov Unique Identifier: NCT00202878



Prognostic Implications of Magnetic Resonance - Derived Quantification in Asymptomatic Patients with Organic Mitral Regurgitation: Comparison with Doppler Echocardiography-Derived Integrative Approach [Original Research Article]

2017-12-21T02:00:23-08:00

Background—Magnetic resonance imaging (MRI) is an accurate method for the quantitative assessment of organic mitral regurgitation (OMR). The aim of the present study was to compare the discriminative power of MRI quantification and the recommended Doppler-echocardiography (ECHO)-derived integrative approach to identify asymptomatic patients with OMR and adverse outcome.Methods—The study population consisted of 258 asymptomatic patients (63±14 years, 60% males) with preserved left ventricular (LV) ejection fraction (>60%) and chronic moderate and severe OMR (flail 25%, prolapse 75%) defined using the ECHO-derived integrative approach. All patients underwent MRI to quantify regurgitant volume (RV) of OMR by subtracting the aortic forward flow volume from the total LV stroke volume. Severe OMR was defined as RV≥60ml.Results—Mean ECHO-derived RV was on average 17.1ml larger than the MRI-derived RV (p<0.05). Concordant grading of OMR severity with both techniques was observed in 197 (76%) individuals with 62 (31%) patients having severe (MRI SEV-ECHO SEV) and 135 (69%) moderate OMR (MRI MOD-ECHO MOD). The remaining 61 (24%) individuals had discordant findings (MRI SEV-ECHO MOD or MRI MOD-ECHO SEV) between the two techniques. The majority of these differences in OMR classification were observed in patients with late systolic or multiple jets (both kappa<0.2). Patients with eccentric jets showed moderate agreement (kappa=0.53, 95%CI 0.41-0.64). In contrast, a very good agreement (kappa=0.90, 95%CI 0.82-0.98) was observed in combination of holosystolic, central and single jet. During a median follow-up of 5.0 years (IQR 3.5-6.0 years), 38 (15%) patients died and 106 (41%) either died or developed indication for mitral valve surgery. In separate Cox regression analyses, the MRI-derived LV end-systolic volume index, RV and OMR category (severe vs. moderate), and the ECHO-derived OMR category were independent predictors of all-cause mortality (all p<0.05). The MRI-derived RV showed the largest area under the curve to predict mortality (0.72) or its combination with development of indication for mitral valve surgery (0.83). Conclusions—The findings of the present study suggest that the MRI-derived assessment of OMR can better identify patients with severe OMR and adverse outcome than ECHO-derived integrative approach warranting close follow-up and perhaps, early mitral valve surgery.



The Efficacy and Safety of the Use of Non-Vitamin-K Antagonist Oral Anticoagulants in Patients with Non-Valvular Atrial Fibrillation and Concomitant Aspirin Therapy: A Meta-Analysis of Randomized Trials [Original Research Article]

2017-11-03T02:00:19-07:00

Background—Current guidelines recommend non-vitamin-K antagonist oral anticoagulants (NOACs) as the first choice therapy in patients with non-valvular atrial fibrillation, as these drugs have several benefits over the vitamin-K antagonists (VKA). It is unknown whether these benefits remain when NOACs have to be combined with aspirin therapy. To assess the efficacy and safety of NOACs compared with VKA in patients with AF and concomitant aspirin therapy, we conducted a systematic review and study based meta-analysis of published randomized controlled trials (RCTs).Methods—A systematic electronic literature search was done in MEDLINE, EMBASE and Cochrane CENTRAL Register of Controlled Trials for studies including published data (i) of patients age ≥18 y with non-valvular AF; (ii) randomizing to either VKA or NOACs; (iii) patients receiving aspirin therapy at any time during the study; and (iv) reporting on all-cause stroke or systemic embolism, vascular death, myocardial infarction, major bleeding and/or intracranial hemorrhage as an outcome. Hazard ratios (HR) with 95% confidence intervals (CIs) for each outcome were extracted from the individual studies and pooled using random-effects meta-analysis.Results—This study based meta-analysis was restricted to the subgroups of patients on aspirin therapy (n=21,722) from four RCTs comparing VKA and NOACs (N=71,681) in non-valvular AF. In this meta-analysis including patients on mainly low-dose aspirin, NOACs were found to be more effective (outcome stroke or systemic embolism HR: 0.78 [95% CI, 0.67-0.91] and vascular death HR 0.85 [0.76-0.93]) and as safe as VKA with respect to major bleeding (HR: 0.83 [95% CI, 0.69-1.01]). NOACs were safer with respect to the reduction of intracranial hemorrhage (HR: 0.38 [0.26-0.56]). Conclusions—This study based meta-analysis shows that it may be both safer and more effective to use NOACs as compared with VKA to treat patients with non-valvular AF and concomitant aspirin therapy.



Cardiorespiratory Fitness, Coronary Artery Calcium and Cardiovascular Disease Events in a Cohort of Generally Healthy, Middle Aged Men: Results from the Cooper Center Longitudinal Study [Original Research Article]

2018-01-17T02:00:23-08:00

Background—A robust literature demonstrates that coronary artery calcification (CAC) and cardiorespiratory fitness (CRF) are independent predictors of cardiovascular disease (CVD) events. Much less is known about the joint associations of CRF and CAC with CVD risk. In the setting of high CAC, high versus low CRF has been associated with decreased CVD events. The goal of this study was to assess the impact of continuous levels of CRF on CVD risk in the setting of increasing CAC burden. Methods—We studied 8,425 men without clinical CVD who underwent preventive medicine examinations that included an objective measurement of CRF and CAC between 1998-2007. There were 383 CVD events during an average follow-up of 8.4 years. Parametric proportional hazards regression models based on a Gompertz mortality rule were used to estimate total CVD incidence rates at age 70 as well as hazard ratios for the included covariates. Results—CVD events increased with increasing CAC and decreased with increasing CRF. Adjusting for CAC level (scores of 0, 1-99, 100-399, and ≥400), for each additional MET of fitness, there was an 11% lower risk for CVD events (Hazard Ratio: 0.89, 95% Confidence Interval: 0.84, 0.94). When CAC and CRF were considered together, there was a strong association between continuous CRF and CVD incidence rates in all CAC groups. Conclusions—In a large cohort of generally healthy men, there is an attenuation of CVD risk at all CAC levels with higher CRF.



D-dimer Predicts Long-Term Cause-Specific Mortality, Cardiovascular Events and Cancer in Stable Coronary Heart Disease Patients: The LIPID Study [Original Research Article]

2018-01-24T02:00:24-08:00

Background—D-dimer, a degradation product of cross-linked fibrin, is a marker for hypercoagulability and thrombotic events. Moderately elevated levels of D-dimer are associated with the risk of venous and arterial events in patients with vascular disease. We assessed the role of D-dimer levels in predicting long-term vascular outcomes, cause-specific mortality, and new cancers in the LIPID trial in the context of other risk factors.Methods—LIPID randomized patients to placebo or pravastatin 40 mg/day 5-38 months after myocardial infarction or unstable angina. D-dimer levels were measured at baseline and at 1 year. Median follow-up was 6.0 years during the trial and 16 years in total.Results—Baseline D-dimer levels for 7863 patients were grouped by quartile (≤112, 112-173, 173-273, >273 ng/mL). Higher levels were associated with older age, female sex, history of hypertension, poor renal function and elevated levels of B-natriuretic peptide, high-sensitivity C-reactive protein, and sensitive troponin I (each P<0.001). During the first 6 years, after adjustment for up to 30 additional risk factors, higher D-dimer was associated with a significantly increased risk of a major coronary event (Q4 vs Q1 HR 1.45; 95% CI 1.21-1.74), major cardiovascular (CVD) event (HR 1.45; 95% CI 1.23-1.71) and venous thromboembolism (HR 4.03 (2.31-7.03; 95% CI 2.31-7.03); each P<0.001. During the 16 years overall, higher D-dimer was an independent predictor of all-cause mortality (HR 1.59), CVD mortality (1.61), cancer mortality (1.54) and non-CVD noncancer mortality (1.57) (each P<0.001), remaining significant for deaths from each cause occurring beyond 10 years of follow-up (each P≤0.01). Higher D-dimer also independently predicted an increase in cancer incidence (HR 1.16, P=0.02).The D-dimer level increased the net reclassification index for all-cause mortality by 4.0 and venous thromboembolism by 13.6.Conclusions—D-dimer levels predict long-term risk of arterial and venous events, CVD mortality, and non-CVD noncancer mortality, independently of other risk factors. D-dimer is also a significant predictor of cancer incidence and mortality. These results support an association of D-dimer with fatal events across multiple diseases and demonstrate that this link extends beyond 10 years' follow-up.



Association Between Hospital Volume, Processes of Care, and Outcomes in Patients Admitted With Heart Failure: Insights From Get With The Guidelines-Heart Failure [Original Research Article]

2018-01-29T01:55:21-08:00

Background—Hospital volume is frequently used as a structural metric for assessing quality of care, but its utility in patients admitted with acute heart failure (HF) is not well characterized. Accordingly, we sought to determine the relationship between admission volume, process-of-care metrics, and short- and long-term outcomes in patients admitted with acute HF.Methods—Patients enrolled in the Get With The Guidelines-HF registry with linked Medicare inpatient data at 342 hospitals were assessed. Volume was assessed both as a continuous variable, and quartiles based on the admitting hospital annual HF case volume, as well: 5 to 38 (quartile 1), 39 to 77 (quartile 2), 78 to 122 (quartile 3), 123 to 457 (quartile 4). The main outcome measures were (1) process measures at discharge (achievement of HF achievement, quality, reporting, and composite metrics); (2) 30-day mortality and hospital readmission; and (3) 6-month mortality and hospital readmission. Adjusted logistic and Cox proportional hazards models were used to study these associations with hospital volume.Results—A total of 125 595 patients with HF were included. Patients admitted to high-volume hospitals had a higher burden of comorbidities. On multivariable modeling, lower-volume hospitals were significantly less likely to be adherent to HF process measures than higher-volume hospitals. Higher hospital volume was not associated with a difference in in-hospital (odds ratio, 0.99; 95% confidence interval [CI], 0.94-1.05; P=0.78) or 30-day mortality (hazard ratio, 0.99; 95% CI, 0.97-1.01; P=0.26), or 30-day readmissions (hazard ratio, 0.99; 95% CI, 0.97-1.00; P=0.10). There was a weak association of higher volumes with lower 6-month mortality (hazard ratio, 0.98; 95% CI, 0.97-0.99; P=0.001) and lower 6-month all-cause readmissions (hazard ratio, 0.98; 95%, CI 0.97-1.00; P=0.025).Conclusions—Our analysis of a large contemporary prospective national quality improvement registry of older patients with HF indicates that hospital volume as a structural metric correlates with process measures, but not with 30-day outcomes, and only marginally with outcomes up to 6 months of follow-up. Hospital profiling should focus on participation in systems of care, adherence to process metrics, and riskstandardized outcomes rather than on hospital volume itself.



Sex and Race Differences in Lifetime Risk of Heart Failure with Preserved Ejection Fraction and Heart Failure with Reduced Ejection Fraction [Original Research Article]

2018-01-19T02:00:18-08:00

Background—Lifetime risk of heart failure has been estimated to range from 20% to 46% in diverse sex and race groups. However, lifetime risk estimates for the two HF phenotypes, HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF), is not known. Methods—Participant-level data from 2 large prospective cohort studies, the Cardiovascular Health Study (CHS) and the Multiethnic Study of Atherosclerosis (MESA), were pooled excluding individuals with prevalent HF at baseline. Remaining lifetime risk estimates for HFpEF (Ejection Fraction ≥ 45%) and HFrEF (Ejection Fraction < 45%) were determined at different index ages using a modified Kaplan-Meier method with mortality and the other HF subtype as competing risks. Results—We included 12,417 participants older than 45 years (22.2% blacks, 44.8% men) who were followed for median duration of 11.6 years with 2,178 overall incident HF events with 561 HFrEF events and 726 HFpEF events. At index age of 45 years, the lifetime risk for any HF through age 90 was higher in men than women (27.4% vs. 23.8%). Among HF subtypes, the lifetime risk for HFrEF was higher in men than women (10.6% vs. 5.8%). In contrast, the lifetime risk for HFpEF was similar in men and women. In race-stratified analyses, lifetime risk for overall HF was higher in non-blacks than blacks (25.9% vs. 22.4%). Among HF subtypes, the lifetime risk for HFpEF was higher in non-blacks than blacks (11.2% vs. 7.7%) while that for HFrEF was similar across the two groups. Among participants with antecedent myocardial infarction (MI) prior to HF diagnosis, the remaining lifetime risks for HFpEF and HFrEF were 2.5-fold and 4-fold higher, respectively, as compared with those without antecedent MI. Conclusions—Lifetime risks for HFpEF and HFrEF vary by sex, race, and history of antecedent MI. These insights into the distribution of HF risk and its subtypes could inform development of targeted strategies to improve population level HF prevention and control.



Derivation and Validation of a Novel Right-Sided Heart Failure Model After Implantation of Continuous Flow Left Ventricular Assist Devices:The EUROMACS (European Registry for Patients with Mechanical Circulatory Support) Right-Sided Heart Failure Risk Score [Original Research Article]

2017-08-27T23:24:12-07:00

Background—The aim of the study was to derive and validate a novel risk score for early right-sided heart failure (RHF) after left ventricular assist device implantation.Methods—The European Registry for Patients with Mechanical irculatory Support (EUROMACS) was used to identify adult patients undergoing continuous-flow left ventricular assist device implantation with mainstream devices. Eligible patients (n=2988) were randomly divided into derivation (n=2000) and validation (n=988) cohorts. The primary outcome was early ([...]



Six-Year Changes in Physical Activity and the Risk of Incident Heart Failure: The Atherosclerosis Risk in Communities (ARIC) Study [Original Research Article]

2018-01-31T02:00:21-08:00

Background—Higher physical activity (PA) is associated with lower heart failure (HF) risk. However, the impact of changes in PA on HF risk is unknown. Methods—We evaluated 11,351 ARIC participants (mean age 60 years) who attended Visit 3 (1993-95) and did not have a history of cardiovascular disease. Exercise PA was assessed using a modified Baecke questionnaire and categorized according to American Heart Association guidelines as recommended, intermediate, or poor. We used Cox regression models to characterize the association of 6-year changes in PA between the first (1987-1989) and third ARIC visits and HF risk. Results—During a median of 19 years of follow-up, there were 1,750 HF events. Compared to those with poor activity at both visits, the lowest HF risk was seen for those with persistently recommended activity (HR 0.69; 95% CI: 0.60, 0.80). However, those whose PA increased from poor to recommended also had reduced HF risk (HR 0.77; 95% CI: 0.63, 0.93). Among participants with poor baseline activity, each 1-SD higher PA at 6 years (512.5 METS*minutes/week; corresponding to approximately 30 minutes of brisk walking 4 times per week) was associated with significantly lower future HF risk (HR: 0.89, 95% CI: 0.82, 0.96). Conclusions—While maintaining recommended activity levels is associated with the lowest HF risk, initiating and increasing PA, even in late middle age, are also linked to lower HF risk. Augmenting PA may be an important component of strategies to prevent HF.



Geographic Variation in Cardiac Rehabilitation Participation in Medicare and Veterans Affairs Populations: An Opportunity for Improvement? [Original Research Article]

2018-01-05T02:00:23-08:00

Background—Cardiac rehabilitation is strongly recommended after myocardial infarction (MI), percutaneous coronary intervention (PCI), or coronary artery bypass surgery (CABG), but is historically underused. We sought to evaluate variation in cardiac rehabilitation participation across the United States.Methods—From administrative data from the Veterans Affairs (VA) healthcare system and a 5% Medicare sample, we used ICD-9 codes to identify patients hospitalized for MI, PCI, or CABG from 2007-2011. After excluding patients who died within 30 days of hospitalization, we calculated the percent of patients who participated in one or more outpatient visits for cardiac rehabilitation during the 12 months after hospitalization. We estimated adjusted and standardized rates of participation in cardiac rehabilitation by state using hierarchical logistic regression models. Results—Overall, participation in cardiac rehabilitation was 16.3% (23,403/143,756) in Medicare and 10.3% (9,123/88,826) in VA. However, participation rates varied widely across states, ranging from 3.2% to 41.8% in Medicare and 1.2% to 47.6% in VA. Similar regional variation was observed in both populations. Patients in the West North Central region (Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota) had the highest participation, while those in the Pacific region (Alaska, California, Hawaii, Oregon, and Washington) had the lowest participation in both Medicare (33.7% vs. 10.6%) and VA (16.6% vs. 5.1%) populations. Significant hospital-level variation was also present, with participation ranging from 3-75% in Medicare and 1-43% in VA.Conclusions—Cardiac rehabilitation participation remains low overall in both Medicare and VA populations. However, there is remarkably similar regional variation, with some regions and hospitals achieving high rates of participation in both populations. This provides an opportunity to identify best practices from higher-performing hospitals and regions that could be used to improve cardiac rehabilitation participation in lower-performing hospitals and regions.



Contribution of Impaired Parasympathetic Activity to Right Ventricular Dysfunction and Pulmonary Vascular Remodeling in Pulmonary Arterial Hypertension [Original Research Article]

2017-11-22T02:00:21-08:00

Background—Beneficial effects of parasympathetic stimulation have been reported in left heart failure, however, whether it would be beneficial for pulmonary arterial hypertension (PAH) remains to be explored. Here, we investigated the relationship between parasympathetic activity and right ventricular (RV) function in PAH-patients, and the potential therapeutic effects of pyridostigmine (PYR), an oral drug stimulating the parasympathetic activity through acetylcholinesterase (AchE) inhibition, in experimental pulmonary hypertension (PH).Methods—Heart rate recovery (HRR) after maximal cardiopulmonary exercise test was used as a surrogate for parasympathetic activity. RV ejection fraction (RVEF) was assessed in 112 PAH-patients. Expression of nicotinic (α-7nAchR) and muscarinic (m2AchR) receptors, and AchE activity were evaluated in RV (n=11) and lungs (n=7) from PAH-patients undergoing heart/lung transplantation and compared with tissue obtained from controls. In addition, we investigated the effects of PYR (40 mg/kg/day) in experimental PH. PH was induced in male rats by SU5416 (25 mg/kg; s.c.) injection followed by 4 weeks of hypoxia. In a subgroup sympathetic/parasympathetic modulation was assessed by power spectral analysis. At week 6, PH status was confirmed by echocardiography, and rats were randomized to vehicle or treatment (both n=12). At the end-of-study, echocardiography was repeated, with additional RV pressure-volume measurements, along with lung, RV histological and protein analyses.Results—PAH-patients with lower RVEF ([...]



DAWN of a New Era for Stroke Treatment: Implications of the DAWN Study for Acute Stroke Care and Stroke Systems of Care [Perspective]

2018-01-18T02:00:20-08:00

Until recently, the selection of patients with large artery occlusion and ischemic stroke for reperfusion therapy was based on time criteria (typically within 6 hours) and basic imaging protocols (head CT, CT angiogram, ASPECTS score). The recently published DAWN (DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention with Trevo) study has changed this paradigm by using a tissue-based selection criteria and a greatly expanded treatment time window (up to 24 hours).1 This is a transformational change in acute stroke therapy and has implications for many healthcare providers and EMS systems.



Complement Receptor C5aR1 Plays an Evolutionarily Conserved Role in Successful Cardiac Regeneration [Original Research Article]

2018-01-18T02:00:21-08:00

Background—Defining conserved molecular pathways in animal models of successful cardiac regeneration could yield insight into why adult mammals have inadequate cardiac regeneration after injury. Insight into the transcriptomic landscape of early cardiac regeneration from model organisms will shed light on evolutionarily conserved pathways in successful cardiac regeneration.Methods—Here we describe a cross-species transcriptomic screen in three model organisms for cardiac regeneration -axolotl, neonatal mice and zebrafish. Apical resection to remove ~10 - 20% of ventricular mass was carried out in these model organisms. RNA-seq analysis was performed on the hearts harvested at three time points - 12, 24 and 48 hours post-resection. Sham surgery was used as internal control. Results—Genes associated with inflammatory processes were found to be upregulated in a conserved manner. Complement receptors (activated by complement components, part of the innate immune system) were found to be highly upregulated in all three species. This approach revealed induction of gene expression for Complement 5a receptor1 (C5aR1) in the regenerating hearts of zebrafish, axolotls and mice. Inhibition of C5aR1 significantly attenuated the cardiomyocyte proliferative response to heart injury in all three species. Furthermore, following left ventricular apical resection, the cardiomyocyte proliferative response was abolished in mice with genetic deletion of C5aR1.Conclusions—These data reveal that activation of C5aR1 mediates an evolutionarily conserved response that promotes cardiomyocyte proliferation following cardiac injury and identify complement pathway activation as a common pathway of successful heart regeneration.



Risk of Dementia in Adults With Congenital Heart Disease: Population-Based Cohort Study [Original Research Article]

2018-02-12T01:55:20-08:00

Background—More children with congenital heart disease (CHD) are surviving to adulthood, and CHD is associated with risk factors for dementia. We compared the risk of dementia in CHD adults to that of the general population.Methods—In this cohort study, we used medical registries and a medical record review covering all Danish hospitals to identify adults with CHD diagnosed between 1963 and 2012. These individuals with CHD were followed from January 1, 1981, 30 years of age, or date of first CHD registration (index date for matched members of the general population cohort) until hospital diagnosis of dementia, death, emigration, or end of study (December 31, 2012). For each individual with CHD, we identified 10 members of the general population utilizing the Danish Civil Registration System matched on sex and birth year. We computed cumulative incidences and hazard ratios (HRs) of dementia, adjusting for sex and birth year.Results—The cumulative incidence of dementia was 4% by 80 years of age in 10 632 adults with CHD (46% male). The overall HR comparing adults with CHD with the general population cohort was 1.6 (95% confidence interval [CI], 1.3−2.0). The HR among individuals with CHD without extracardiac defects was 1.4 (95% CI, 1.1−1.8). Adults with mild-to-moderate CHD had an HR of 1.5 (95% CI, 1.1−2.0), whereas the HR was 2.0 (95% CI, 1.2−3.3) for severe CHD, including univentricular hearts. The HR for early onset dementia (<65 years of age) was 2.6 (95% CI, 1.8−3.8), whereas the late-onset HR was 1.3 (95% CI, 1.0−1.8).Conclusions—CHD was associated with an increased risk of dementia compared with the general population, in particular for early onset dementia. Further understanding of dementia risk in the population with CHD is a potential target for future investigation.



Statins Have a Dose-Dependent Effect on Amputation and Survival in Peripheral Artery Disease Patients [Original Research Article]

2018-01-12T02:00:20-08:00

Background—Statin dose guidelines for Peripheral Artery Disease (PAD) patients are largely based on coronary artery disease and stroke data. The aim of this study is to determine the effect of statin intensity on PAD outcomes of amputation and mortality. Methods—Using an observational cohort study design and a validated algorithm we identified incident PAD patients (2003-2014) in the national Veterans Affairs data. Highest statin intensity exposure [high intensity vs low- moderate intensity vs antiplatelet therapy but no statin use (AP only)] was determined within one year of diagnosis of PAD. Outcomes of interest were lower extremity amputations and death. The association of statin intensity with incident amputation and mortality was assessed with Kaplan Meier plots, Cox proportional hazards modeling, propensity score (PS) matched analysis as well as sensitivity and subgroup analyses to reduce confounding.Results—In 155,647 patients with incident PAD, more than a quarter (28%) were not on statin. Use of high intensity statins was lowest in patients with PAD only (6.4%) as compared to comorbid coronary/carotid disease (18.4%). Incident amputation and mortality risk declined significantly with any statin use compared to AP only group. In adjusted Cox models, the high intensity statin users were associated with lower amputation risk and mortality as compared to AP only users [HR 0.67; 95% CI (0.61, 0.74) and HR 0.74; 95% CI (0.70, 0.77), respectively]. Low-moderate intensity statins also had significant reductions in risk of amputation and mortality [HR amputation 0.81 (0.75, 0.86), HR death 0.83 (0.81, 0.86)] as compared to no statins (AP only) but effect size was significantly weaker than the high intensity statins (p[...]



Functional Metabolomics Characterizes a Key Role for N-Acetyl-Neuraminic Acid in Coronary Artery Diseases [Original Research Article]

2017-12-06T01:55:17-08:00

Background—As new biomarkers of coronary artery diseases (CAD) emerge via metabolomics, the underlying functional mechanisms remain to be elucidated. Functional metabolomics aims to translate metabolomics-derived biomarkers to disease mechanisms.Methods—A cohort of 2324 patients who underwent coronary angiography from 4 independent centers was studied. A combination of ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) in the negative ion mode was employed for untargeted analysis of metabolites in plasma. Significant differential metabolites were identified by cross comparisons with and within CAD types, including normal coronary artery (NCA), nonobstructvie coronary atherosclerosis (NOCA), stable angina (SA), unstable angina (UA), and acute myocardial infarction (AMI). A tandem LC-MS-based approach using isotope-labeled standard addition was subsequently performed for targeted analysis of the metabolic marker N-Acetyl-neuraminic acid (Neu5Ac). Finally, a functional metabolomics strategy was proposed to investigate the role of Neu5Ac, in the progression of CAD using in vitro and in vivo models. Results—We identified a total of 36 differential metabolites, 35 of which were confirmed with reference compounds. Elevation of Neu5Ac was observed in plasma during CAD progression in Center 1 (p = 4.0e-64, n = 2019), and replicated in 3 independent Centers (n = 305). The increased level of Neu5Ac in plasma was confirmed by accurate targeted quantification. Mechanistically, Neu5Ac was able to trigger myocardial injury in vitro and in vivo by activation of Rho-ROCK signaling pathway through binding to RhoA and Cdc42, but not Rac1. Silencing neuraminidase-1, the enzyme that regulates Neu5Ac generation, ameliorated oxygen-glucose deprivation-induced injury in cardiomyocytes and ligation/isoprenaline-induced myocardial ischemia injury in rats. Pharmacological inhibition of neuraminidase by anti-influenza drugs, oseltamivir and zanamivir, also protected cardiomyocytes and the heart from myocardial injury. Conclusions—Functional metabolomics identified a key role for Neu5Ac i[...]



Status of Hypertension in China: Results from the China Hypertension Survey, 2012-2015 [Original Research Article]

2018-02-15T02:00:24-08:00

Background—Although the prevalence of hypertension (HTN) continues to increase in developing countries including China, recent data are lacking. A national wide survey was conducted from October 2012 to December 2015 to assess the prevalence of HTN in China. Methods—A stratified multistage random sampling method was used to obtain a nationally representative sample of 451,755 residents aged ≥18 years from 31 provinces in mainland China from October 2012 to December 2015. Blood pressure (BP) was measured after resting for 5 minutes by trained staff, using a validated oscillometric BP monitor. HTN was defined as systolic BP (SBP) ≥140 mmHg and/or /diastolic BP (DBP) ≥90 mmHg and/or use of antihypertensive medication within two weeks. Pre-HTN was defined as SBP 120-139 mmHg and DBP 80-89 mmHg without antihypertensive medication. HTN control was defined as SBP [...]



Inhibition of JAK-STAT Signaling Suppresses Pathogenic Immune Responses in Medium and Large Vessel Vasculitis [Original Research Article]

2017-12-18T02:00:21-08:00

Background—Giant cell arteritis (GCA), a chronic autoimmune disease of the aorta and its large branches, is complicated by aneurysm formation, dissection, and arterial occlusions. Arterial wall dendritic cells (DC) attract CD4+ T-cells and macrophages (Mo), to form prototypic granulomatous infiltrates. Vasculitic lesions contain a diverse array of effector T-cells that persist despite corticosteroid therapy and sustain chronic, smoldering vasculitis. Transmural inflammation induces microvascular neoangiogenesis and results in lumen-occlusive intimal hyperplasia. We have examined whether persistent vessel wall inflammation is maintained by lesional T-cells, including the newly identified tissue-resident memory T cells (TRM) and whether such T-cells are sensitive to the cytokine signaling inhibitor tofacitinib, a JAK inhibitor (Jakinib) targeting the Janus kinase (JAK) 3 and JAK1.Methods—Vascular inflammation was induced in human arteries engrafted into immunodeficient mice that were reconstituted with T-cells and monocytes from GCA patients. Mice carrying inflamed human arteries were treated with tofacitinib or vehicle. Vasculitic arteries were examined for gene expression (RT-PCR), protein expression (immunohistochemistry) and infiltrating cell populations (flow cytometry). Results—Tofacitinib effectively suppressed innate and adaptive immunity in the vessel wall. Lesional T-cells responded to tofacitinib with reduced proliferation rates (<10%) and minimal production of the effector molecules IFN-γ, IL-17 and IL-21. Tofacitinib disrupted adventitial microvascular angiogenesis, reduced outgrowth of hyperplastic intima and minimized CD4+CD103+ tissue-resident memory T-cells.Conclusions—Cytokine signaling dependent on JAK3 and JAK1 is critically important in chronic inflammation of medium and large arteries. The Jakinib tofacitinib effectively suppresses tissue-resident memory T-cells and inhibits core vasculitogenic effector pathways.



An International External Validation Study of the 2014 European Society of Cardiology Guideline on Sudden Cardiac Death Prevention in Hypertrophic Cardiomyopathy (Evidence from HCM) [Original Research Article]

2017-11-30T02:00:20-08:00

Background—Identification of people with hypertrophic cardiomyopathy (HCM) who are at risk of sudden cardiac death (SCD) and require prophylactic implantable cardioverter defibrillator (ICD) is challenging. In 2014, the European Society of Cardiology (ESC) proposed a new risk stratification method based on a risk prediction model (HCM Risk-SCD) which estimates the 5-year risk of SCD. The aim was to externally validate the 2014 ESC recommendations in a geographically diverse cohort of patients recruited from North America, Europe, The Middle East and Asia.Methods—This was an observational, retrospective, longitudinal cohort study.Results—The cohort consisted of 3703 patients. Seventy three (2%) patients reached the SCD end-point within 5 years of follow-up [5-year incidence 2.4% (95% CI 1.9, 3.0)]. The validation study revealed a calibration slope of 1.02 (95% CI 0.93 to 1.12); C-index 0.70 (95% CI 0.68 to 0.72) and D-statistic 1.17 (95% CI 1.05 to 1.29). In a complete case analysis (n= 2147; 44 SCD end-points at 5 years) patients with a predicted 5-year risk of <4% (n=1524; 71%) had an observed 5-year SCD incidence of 1.4% (95% CI 0.8, 2.2); patients with a predicted risk of ≥6% (n=297; 14%) had an observed SCD incidence of 8.9% (95% CI 5.96, 13.1) at 5 years. For every 13 (297/23) ICD implantations in patients with an estimated 5 year SCD risk ≥6%, 1 patient can potentially be saved from SCD.Conclusions—This study confirms that the HCM Risk-SCD model provides accurate prognostic information which can be used to target ICD therapy in patients at the highest risk of SCD.



Cardiovascular Complications in Pregnancy: It Is Time for Action [On My Mind]

2018-02-19T11:00:32-08:00

Cardiovascular disease (CVD) is the leading cause of death during pregnancy, accounting for ≈33% of the maternal deaths in the United States.1 There is also increasing evidence that there is a significant link between complications of pregnancy and CVD later in life. Pregnancy complications such as preeclampsia, gestational diabetes mellitus, gestational hypertension, preterm delivery, and delivery of an infant with growth restriction provide signals about the mother's cardiovascular adaptability of physiological stress. It is time to change the paradigm for identifying and preventing CVD in women.



Pericardial Adipose Tissue Regulates Granulopoiesis, Fibrosis and Cardiac Function After Myocardial Infarction [Original Research Article]

2017-11-22T02:00:18-08:00

Background—The pericardial adipose tissue (AT) contains a high density of lymphoid clusters. Is unknown whether these clusters play a role in post-myocardial infarction (MI) inflammatory responses and cardiac outcome.Methods—Lymphoid clusters were examined in epicardial AT of humans with or without coronary artery disease (CAD). Murine pericardial lymphoid clusters were visualized in mice subjected to coronary artery ligation. To study the relevance of pericardial clusters during inflammatory responses after MI, we surgically removed the pericardial AT, performed B cell depletion and GM-CSF blockade. Leukocytes in murine hearts, pericardial AT, spleen, mediastinal lymph nodes, and bone marrow were quantified by flow cytometry. Cannabinoid receptor CB2 (CB2-/-) mice were used as a model for enhanced B cell responses. The effect of impaired dendritic cell (DC) trafficking on pericardial AT inflammatory responses was tested in CCR7-/- mice subjected to MI. Cardiac fibrosis and ventricular function were assessed by histology and echocardiography.Results—We identified larger B cell clusters in epicardial AT of human CAD patients compared to controls without CAD. Infarcted mice also had larger pericardial clusters and 3-fold upregulated numbers of GM-CSF-producing B cells within pericardial AT, but not spleen or lymph nodes. This was associated with higher DC and T cell counts in pericardial AT, which outnumbered DCs and T cells in lymph nodes. Analysis of DC maturation markers, tracking experiments with fluorescently labelled cells and use of CCR7-deficient mice suggested that activated DCs migrate from infarcts into pericardial AT via CCR7. B cell depletion or GM-CSF neutralization inhibited DC and T cell expansion within pericardial AT, and translated into reduced bone marrow granulopoiesis and cardiac neutrophil infiltration 3 days after MI. The relevance of the pericardial AT in mediating all these effects was confirmed by removal of pericardial AT and ex vivo coculture with peric[...]



Improving Assessment of Drug Safety Through Proteomics: Early Detection and Mechanistic Characterization of the Unforeseen Harmful Effects of Torcetrapib [Original Research Article]

2017-10-03T02:00:27-07:00

Background—Early detection of adverse effects of novel therapies and understanding of their mechanisms could improve the safety and efficiency of drug development. We have retrospectively applied large-scale proteomics to blood samples from ILLUMINATE, a trial of torcetrapib (a cholesterol ester transfer protein inhibitor), that involved 15,067 participants at high cardiovascular risk. ILLUMINATE was terminated at a median of 550 days due to significant absolute increases of 1.2% in cardiovascular events and 0.4% in mortality with torcetrapib. The aims of our analysis were to determine: 1) whether a proteomic analysis might reveal biological mechanisms responsible for these harmful effects and 2) whether harmful effects of torcetrapib could have been detected early in the ILLUMINATE trial using proteomics.Methods—A nested case-control analysis of paired plasma samples, at baseline and at 3-months, was performed in 249 participants assigned to torcetrapib plus atorvastatin and 223 participants assigned to atorvastatin only. Within each treatment arm, cases with events were matched to controls, 1:1. Main outcomes were: 1) a survey of 1,129 proteins for discovery of biological pathways altered by torcetrapib, 2) a 9-protein risk score validated to predict myocardial infarction, stroke, heart failure or death. Results—Plasma concentrations of 200 proteins changed significantly with torcetrapib. Their pathway analysis revealed unexpected and widespread changes in immune and inflammatory functions, as well as changes in endocrine systems, including in aldosterone function and glycemic control. At baseline, 9-protein risk scores were similar in the two treatment arms and higher in participants with subsequent events. At 3 months, the absolute 9-protein derived risk increased in the torcetrapib plus atorvastatin arm compared to the atorvastatin only arm by +1.08% (p=0.0004). Thirty-seven proteins changed in the direction of increased risk out of 49 proteins pre[...]



A Comparison of Reduced-Dose Prasugrel and Standard-Dose Clopidogrel in Elderly Patients with Acute Coronary Syndromes Undergoing Early Percutaneous Revascularization [Original Research Article]

2018-02-19T11:00:32-08:00

Background—Elderly patients are at elevated risk of both ischemic and bleeding complications after an acute coronary syndrome (ACS), and display higher on-clopidogrel platelet reactivity as compared to younger patients. Prasugrel 5 mg provides more predictable platelet inhibition, as compared to clopidogrel, in the elderly, suggesting the possibility of reducing ischemic events without increasing bleeding.Methods—In a multicenter, randomized, open-label, blinded-endpoint trial, we compared a once daily maintenance dose of prasugrel 5 mg with the standard clopidogrel 75 mg in patients >74 years with ACS undergoing percutaneous coronary intervention (PCI). The primary endpoint was the composite of mortality, myocardial infarction, disabling stroke and re-hospitalization for cardiovascular causes or bleeding within one year. The study was designed to demonstrate superiority of prasugrel 5 mg over clopidogrel 75 mg.Results—Enrolment was interrupted, according to pre-specified criteria, after a planned interim analysis, when 1443 patients (40% women, mean age 80 years) had been enrolled, with a median follow-up of 12 months, due to futility for efficacy. The primary endpoint occurred in 121 patients (17%) with prasugrel and 121 (16.6%) with clopidogrel (HR 1.007, 95% CI, 0.78-1.30; P =0.955). Definite/probable stent thrombosis rates were 0.7% with prasugrel vs 1.9% with clopidogrel (OR 0.36, C.I. 0.13-1.00, p=0.06). Bleeding Academic Research Consortium types ≥2 were 4.1% with prasugrel vs 2.7% with clopidogrel (OR 1.52, C.I. 0.85-3.16, P= 0.18).Conclusions—The present study in elderly ACS patients showed no difference in the primary endpoint between reduced-dose prasugrel and standard-dose clopidogrel. However, the study should be interpreted in the light of premature termination of the trial. Clinical Trial Registration—URL: https://clinicaltrials.gov/ Unique Identifier: NCT01777503



Association Between Early Hyperoxia Exposure After Resuscitation from Cardiac Arrest and Neurological Disability: A Prospective Multi-Center Protocol-Directed Cohort Study [Original Research Article]

2018-02-01T02:00:21-08:00

Background—Studies examining the association between hyperoxia exposure after resuscitation from cardiac arrest and clinical outcomes have reported conflicting results. Our objective was to test the hypothesis that early post-resuscitation hyperoxia is associated with poor neurological outcome.Methods—Multi-center, prospective cohort study. We included adult, cardiac arrest patients who were mechanically ventilated and received targeted temperature management after return of spontaneous circulation (ROSC). We excluded patients with cardiac arrest due to trauma or sepsis. Per protocol, partial pressure of arterial oxygen (PaO2) was measured at one and six hours after ROSC. Hyperoxia was defined as a PaO2 > 300 mmHg during the initial six hours after ROSC. The primary outcome was poor neurological function at hospital discharge, defined as a modified Rankin Scale > 3. Multivariable generalized linear regression with a log link was used to test the association between PaO2 and poor neurological outcome. To assess if there was an association between other supranormal PaO2 levels and poor neurological outcome, we used other PaO2 cut points to define hyperoxia (i.e. 100, 150, 200, 250, 350, 400 mmHg).Results—Of the 280 patients included, 105 (38%) had exposure to hyperoxia. Poor neurological function at hospital discharge occurred in 70% of patients in the entire cohort, and 77% vs. 65% among patients with and without exposure to hyperoxia respectively [absolute risk difference 12% (95% CI 1% - 23%)]. Hyperoxia was independently associated with poor neurological function, relative risk 1.23 (95% CI 1.11 - 1.35). On multivariable analysis, a one-hour longer duration of hyperoxia exposure was associated with a 3% increase in risk of poor neurological outcome [relative risk 1.03 (95% CI 1.02 - 1.05)]. We found the association with poor neurological outcome began at 300 mmHg or higher. Conclusions—Early hyp[...]



Genetic and Functional Profiling of CD16-Dependent Natural Killer Activation Identifies Patients at Higher Risk of Cardiac Allograft Vasculopathy [Original Research Article]

2017-11-02T02:00:20-07:00

Background—Cardiac transplantation is an effective therapy for end-stage heart failure. As cardiac allograft vasculopathy (CAV) is the major cause of late mortality after heart transplant (HT), there is a need to identify markers that reflect inflammatory or cytotoxic immune mechanisms contributing to its onset. Non-invasive and early stratification of patients at risk remains a challenge for adapting individualized therapy. The CD16 (Fc-gamma receptor 3A, FCGR3A) receptor was recently identified as a major determinant of antibody-mediated natural killer (NK) cell activation in HT biopsies; however, little is known about the role of CD16 in promoting allograft vasculopathy. This study aimed to investigate whether markers that reflect CD16-dependent circulating NK cell activation may identify patients at higher risk of developing CAV after HT.Methods—Blood samples were collected from 103 patients undergoing routine coronarography angiography for CAV diagnosis (median 5 years since HT). Genomic and phenotypic analyses of FCGR3A/CD16 Fc-receptor (FcR) profiles were compared in CAV-positive (n=52) and CAV-free patients (n=51). The levels of CD16 expression and rituximab-dependent cell cytotoxic activity of peripheral NK cells in heart transplant recipients (HTRs) were evaluated using a non-invasive NK-cellular humoral activation test (NK-CHAT). Results—Enhanced levels of CD16 expression and antibody-dependent NK cell cytotoxic function of HTRs were associated with the FCGR3A-VV genotype. The frequency of the FCGR3A-VV genotype was significantly higher in the CAV+ group (odds ratio (OR): 3.9, p=0.0317) than in the CAV- group. The FCGR3A-VV genotype was identified as an independent marker correlated with the presence of CAV at the time of coronary angiography using multivariate logistic regression models. The FCGR3A-VV genotype was also identified as a baseline independent predi[...]



The Failing Heart Stimulates Tumor Growth by Circulating Factors [Original Research Article]

2018-02-19T02:00:25-08:00

Background—Heart failure (HF) survival has improved and nowadays many patients with HF die from non-cardiac causes, including cancer. Our aim was to investigate whether a causal relationship exists between HF and the development of cancer.Methods—HF was induced by inflicting large anterior myocardial infarction (MI) in APCmin mice, which are prone to develop precancerous intestinal tumors, and tumor growth was measured. In addition, to rule out hemodynamic impairment, a heterotopic heart transplantation model was employed, where an infarcted or sham-operated heart was transplanted into a recipient mouse, while the native heart was left in situ. After 6 weeks, tumor number, volume, and proliferation were quantified. Candidate secreted proteins were selected because they were previously associated both with (colon) tumor growth and with myocardial production in post-MI proteomic studies. Myocardial gene expression levels of these selected candidates were analyzed, as well as their proliferative effects on HT-29 (colon cancer) cells. We validated these candidates by measuring them in plasma of healthy subjects and HF patients. Finally, we associated the relation between cardiac specific and inflammatory biomarkers and new-onset cancer in a large prospective general population cohort.Results—The presence of failing hearts, both native and heterotopically transplanted, resulted in significantly increased intestinal tumor load of 2.4fold in APCmin mice (all P[...]



Ventricular Fibrillation Conversion Testing After Implantation of a Subcutaneous Implantable Cardioverter Defibrillator: A Report from the National Cardiovascular Data Registry [Original Research Article]

2018-02-20T02:00:22-08:00

Background—Compared to transvenous (TV) implantable cardioverter defibrillators (ICD), subcutaneous (S) ICDs require a higher energy for effective defibrillation. Although ventricular fibrillation (VF) conversion testing (CT) is recommended after S-ICD implantation to ensure an adequate margin between the defibrillation threshold and maximum device output (80J), prior work found that adherence to this recommendation is declining. Methods—We studied first time S-ICD recipients (between September 28, 2012 and April 1, 2016) in the National Cardiovascular Database Registry ICD Registry to determine: predictors of use of CT, predictors of an insufficient safety margin (ISM, defined as VF conversion energy >65J) during testing, and in-hospital outcomes associated with use of CT. Multivariable logistic regression analysis was used to predict use of CT and ISM. Inverse probability weighted logistic regression analysis was used to examine the association between use of CT and in-hospital adverse events including death. Results—CT testing was performed in 70.7% (n=5,624) of 7,960 S-ICD patients. Although deferral of CT was associated with several patient characteristics (including increased body mass index, increased body surface area, severely reduced ejection fraction, dialysis dependence, warfarin use, anemia, hypertrophic cardiomyopathy), the facility effect was comparatively more important (area under the curve for patient level versus generalized linear mixed model: 0.619 vs. 0.877). An ISM occurred in 6.9% (n=336) of 4,864 patients without a prior ICD and was more common among white patients and those with ventricular pacing on the pre-implant ECG, higher pre-implant blood pressure, larger body surface area, higher body mass index, and lower ejection fraction. A risk score was able to identify patients at low (10%) for I[...]



Application of Large Scale Aptamer-Based Proteomic Profiling to "Planned" Myocardial Infarctions [Original Research Article]

2017-12-08T01:55:17-08:00

Background—Emerging proteomic technologies using novel affinity-based reagents allow for efficient multiplexing with high sample throughput. To identify early biomarkers of myocardial injury, we recently applied an aptamer-based proteomic profiling platform that measures 1,129 proteins to samples from patients undergoing septal alcohol ablation for hypertrophic cardiomyopathy, a human model of "planned myocardial injury" (PMI). Here we examined the scalability of this approach using a markedly expanded platform to study a far broader range of human proteins in the context of myocardial injury. Methods—We applied a highly multiplexed, expanded proteomic technique that uses single stranded DNA aptamers to assay 4,783 human proteins (4,137 distinct human gene targets) to derivation and validation cohorts of PMI, to individuals with spontaneous myocardial infarction (SMI), and to at-risk controls. Results—We found 376 target proteins that significantly changed in the blood after PMI in a derivation cohort (n=20; P < 1.05E-05, one-way repeated measures ANOVA, Bonferroni- threshold). Two hundred forty-seven of these proteins were validated in an independent PMI cohort (n=15; P < 1.33E-04, one-way repeated measures ANOVA); > 90% were directionally consistent and reached nominal significance in the validation cohort. Among the validated proteins that were increased within 1 hour after PMI, 29 were also elevated in patients with spontaneous myocardial infarction (n=63; P < 6.17E-04). Many of the novel markers identified in our study are intracellular proteins not previously identified in the peripheral circulation or have functional roles relevant to myocardial injury. For example, the cardiac LIM protein cysteine and glycine-rich protein 3 (CSRP3) is thought to mediate cardiac mechanotransduction and[...]



Spontaneous Coronary Artery Dissection: Current State of the Science: A Scientific Statement From the American Heart Association [AHA Scientific Statements]

2018-02-22T01:40:24-08:00

Spontaneous coronary artery dissection (SCAD) has emerged as an important cause of acute coronary syndrome, myocardial infarction, and sudden death, particularly among young women and individuals with few conventional atherosclerotic risk factors. Patient-initiated research has spurred increased awareness of SCAD, and improved diagnostic capabilities and findings from large case series have led to changes in approaches to initial and long-term management and increasing evidence that SCAD not only is more common than previously believed but also must be evaluated and treated differently from atherosclerotic myocardial infarction. High rates of recurrent SCAD; its association with female sex, pregnancy, and physical and emotional stress triggers; and concurrent systemic arteriopathies, particularly fibromuscular dysplasia, highlight the differences in clinical characteristics of SCAD compared with atherosclerotic disease. Recent insights into the causes of, clinical course of, treatment options for, outcomes of, and associated conditions of SCAD and the many persistent knowledge gaps are presented.



Long-Term Potassium Monitoring and Dynamics in Heart Failure and Risk of Mortality [Original Research Article]

2017-10-12T02:00:21-07:00

Background—The prognostic value of long-term potassium monitoring and dynamics in heart failure (HF) has not been characterized completely. We sought to determine the association between serum potassium values collected at follow-up with all-cause mortality in a prospective and consecutive cohort of patients discharged from a previous acute HF admission. Methods—Serum potassium was measured at every physician-patient encounter, including hospital admissions and ambulatory settings. The multivariable-adjusted association of serum potassium with mortality was assessed using comprehensive state-of-the-art regression methods that can accommodate time-dependent exposure modeling.Results—The study sample included 2164 patients with a total of 16,116 potassium observations. Mean potassium at discharge was 4.3±0.48 mEq/L. Hypokalemia (5 mEq/L) were observed at the index admission in 77 (3.6%), 1965 (90.8%), and 122 (5.6%) patients, respectively. At a median follow-up of 2.8 years (range=0.03-12.8 years), 1090 patients died (50.4%). On a continuous scale, the multivariable-adjusted association of potassium values and mortality revealed a non-linear association (U-shaped) with higher risk at both ends of its distribution (omnibus p-value=0.001). Likewise, the adjusted hazard ratios (HRs) for hypokalemia and hyperkalemia - normokalemia as reference - were 2.35 (95% confidence interval [CI]:1.40-3.93; p=0.001) and 1.55 (95% CI:1.11-2.16; p=0.011), respectively (omnibus p-value=0.0003). Furthermore, dynamic changes in potassium were independently associated with substantial differences in mortality risk. Potassium normalization was independently associated with lower mortality risk (p=0.001). Conclusions—Either modeled continuously or categorically[...]



Atrial Fibrillation Burden in Young Patients with Congenital Heart Disease [Original Research Article]

2017-11-01T02:00:24-07:00

Background—Patients with congenital heart disease (CHD) are assumed to be vulnerable to atrial fibrillation (AF) due to residual shunts, anomalous vessel anatomy, progressive valvulopathy, hypertension, and atrial scars from previous heart surgery. However, the risk of developing AF as well as the complications associated with AF in children and young adults with CHD have not been compared with those in controls.Methods—Data from the Swedish Patient and Cause of Death Registers were used to identify all patients with a diagnosis of CHD who were born from 1970 to 1993. Each patient with CHD was matched by birth year, sex, and county with 10 controls from the Total Population Register in Sweden. Follow-up data were collected until 2011.Results—Among 21,982 patients (51.6% men) with CHD and 219,816 matched controls, 654 and 328 developed AF, respectively. The mean follow-up was 27 years. The risk of developing AF was 21.99 times higher (95% confidence interval, 19.26-25.12) in patients with CHD than controls. According to a hierarchic CHD classification, patients with conotruncal defects had the highest risk (hazard ratio, 84.27; 95% confidence interval, 56.86-124.89). At the age of 42 years, 8.3% of all patients with CHD had a recorded diagnosis of AF. Heart failure was the quantitatively most important complication in patients with CHD and AF, with a 10.7% (70/654) recorded diagnosis of heart failure.Conclusions—The risk of AF in children and young adults with CHD was 22 times higher than that in matched controls. Up to the age of 42 years, 1 of 12 patients with CHD had developed AF and 1 of 10 patients with CHD with AF had developed heart failure. The patient groups with the most complex congenital defects car[...]