Introduction: In vitro, ST2 is a marker of myocyte stress and inflammation but in vivo, there is no trans-cardiac ST2 concentration step-up to support cardiac ST2 activation in human heart failure (HF) calling into question the source of ST2 in HF. While ST2 is predictive of adverse outcomes in HF, the relationship between ST2 and key pathophysiologic domains in HF with preserved ejection fraction (HFpEF) is not well characterized. Hypothesis: ST2 levels increase in proportion to the severity of left ventricular (LV) remodeling and dysfunction in HFpEF. Methods: At enrollment, patients (n=174) from the RELAX trial testing sildenafil in HFpEF had serum ST2 levels measured and underwent assessment of pathophysiologic domains including congestion, cardiac structure and function, exercise performance (peak oxygen consumption (VO2)) and biomarkers of neurohumoral activation (NT-proBNP, aldosterone, endothelin-1), renal dysfunction (cystatin-C), fibrosis (pro-collagen III N-terminal peptide [NTP], C-telopeptide for type I collagen [CITP]), inflammation (high-sensitivity CRP [hsCRP]) and myocardial necrosis (high-sensitivity troponin-I [hsTnI]). Analysis adjusted for sex, a covariate associated with ST2 levels in normal persons. Results: See table. ST2 was associated with greater congestion, worse right ventricular (RV) pressure overload and dysfunction, lower peak VO2 and biomarkers of neurohumoral activation, renal dysfunction, fibrosis and myocardial necrosis and tended to be associated with systemic inflammation (hsCRP). ST2 was not associated with LV structure or LV systolic or diastolic function. Conclusions: In HFpEF, ST2 was associated with measures of right sided congestion, RV overload and dysfunction, exercise intolerance and other systemic markers of more advanced HF but not with LV structure or LV systolic or diastolic function. These data suggest that mechanisms distinct from LV stress stimulate ST2 activation in HFpEF.
Placental senescence pathophysiology is shared between peripartum cardiomyopathy and preeclampsia in mouse and human
Peripartum cardiomyopathy (PPCM) is an idiopathic form of pregnancy-induced heart failure associated with preeclampsia. Circulating factors in late pregnancy are thought to contribute to both diseases, suggesting a common underlying pathophysiological process. However, what drives this process remains unclear. Using serum proteomics, we identified the senescence-associated secretory phenotype (SASP), a marker of cellular senescence associated with biological aging, as the most highly up-regulated pathway in young women with PPCM or preeclampsia. Placentas from women with preeclampsia displayed multiple markers of amplified senescence and tissue aging, as well as overall increased gene expression of 28 circulating proteins that contributed to SASP pathway enrichment in serum samples from patients with preeclampsia or PPCM. The most highly expressed placental SASP factor, activin A, was associated with cardiac dysfunction or heart failure severity in women with preeclampsia or PPCM. In a murine model of PPCM induced by cardiomyocyte-specific deletion of the gene encoding peroxisome proliferator–activated receptor γ coactivator-1α, inhibiting activin A signaling in the early postpartum period with a monoclonal antibody to the activin type II receptor improved heart function. In addition, attenuating placental senescence with the senolytic compound fisetin in late pregnancy improved cardiac function in these animals. These findings link senescence biology to cardiac dysfunction in pregnancy and help to elucidate the pathogenesis underlying cardiovascular diseases of pregnancy.
Endpoint adjudication in cardiovascular clinical trials
Abstract Endpoint adjudication (EA) is a common feature of contemporary randomized controlled trials (RCTs) in cardiovascular medicine. Endpoint adjudication refers to a process wherein a group of expert reviewers, known as the clinical endpoint committee (CEC), verify potential endpoints identified by site investigators. Events that are determined by the CEC to meet pre-specified trial definitions are then utilized for analysis. The rationale behind the use of EA is that it may lessen the potential misclassification of clinical events, thereby reducing statistical noise and bias. However, it has been questioned whether this is universally true, especially given that EA significantly increases the time, effort, and resources required to conduct a trial. Herein, we compare the summary estimates obtained using adjudicated vs. non-adjudicated site designated endpoints in major cardiovascular RCTs in which both were reported. Based on these data, we lay out a framework to determine which trials may warrant EA and where it may be redundant. The value of EA is likely greater when cardiovascular trials have nuanced primary endpoints, endpoint definitions that align poorly with practice, sub-optimal data completeness, greater operator variability, and lack of blinding. EA may not be needed if the primary endpoint is all-cause death or all-cause hospitalization. In contrast, EA is likely merited for more nuanced endpoints such as myocardial infarction, bleeding, worsening heart failure as an outpatient, unstable angina, or transient ischaemic attack. A risk-based approach to adjudication can potentially allow compromise between costs and accuracy. This would involve adjudication of a small proportion of events, with further adjudication done if inconsistencies are detected.
Effect of Treatment With Sacubitril/Valsartan in Patients With Advanced Heart Failure and Reduced Ejection Fraction
Background: The Acute Decompensated Heart Failure National Registry (ADHERE) risk levels are a validated tool to assess the risk of in-hospital mortality in patients with acute decompensated heart failure (ADHF). The objective of this study is to determine if the risk levels predict 60-day outcomes in well-defined ADHF patients from NIH Heart Failure Clinical Research Network (HFCRN) trials. Methods: Our study cohort included 835 unique patients with ADHF enrolled in 3 NIH HFCRN trials: Diuretic Optimization Strategies Evaluation (DOSE), CARdiorenal REScue Study in Acute Decompensated Heart Failure (CARRESS-HF), and Renal Optimization Strategies Evaluation (ROSE). ADHERE risk level was assigned, as previously described, by baseline BUN (<43 vs. ≥43 mg/dL), Cr (<2.2 vs. ≥2.2, a modification from 2.75 mg/dL used in ADHERE due the Cr distribution in our study population), and systolic BP (≥ 115 vs < 115 mmHg). Baseline characteristics and outcomes were compared between risk levels. Results: Of the 835 patients enrolled in DOSE (308), CARRESS-HF (188), and ROSE (360), an ADHERE risk level could be assigned to 830, with 62 (8%) high, 521 (63%) intermediate, 247 (30%) low risk. Baseline characteristics (Table 1) and outcomes (Table 2), including combined 60-day death and re-hospitalization (hazard ratio 1.94, high risk versus low risk, p<0.01), varied by ADHERE risk level. Conclusion: ADHERE risk levels predict 60-day death and re-hospitalization rates in patients with ADHF. These results extend the utility of the ADHERE risk levels, by informing longer-term clinical decisions regarding advanced heart failure treatment, care transition strategies and clinical trial design.
Abstract 10990: Regulatory Implications of Different Definitions and Outcomes in Worsening Heart Failure
Introduction: Despite the use of different definitions for worsening heart failure (WHF) in prior clinical trials and registries, an in-hospital WHF event has consistently been associated with worse patient outcomes. WHF is being considered as a potential endpoint to support drug approval. We combined patients from two acute HF trials conducted by the HF Network (ROSE-AHF and DOSE-AHF) to understand how different WHF definitions are associated with event rates. Methods: WHF was defined as persistent or worsening HF requiring rescue therapy including IV vasoactive agents, ultrafiltration, or mechanical support over 72 hours after randomization in ROSE and also included additional open label loop or thiazide diuretic in DOSE. We assessed the relationship between WHF and the composite endpoint (CE) of re-hospitalization, emergency room visits for HF and mortality through 60 days. We also assessed for a differential relationship of WHF from 0-24 hours, 24-48 hours and 48-72 hours post-randomization. Results: The overall incidence of WHF was 14.6% (24.1% in DOSE and 6.3% in ROSE). Patients who developed WHF had lower baseline systolic blood pressure, less peripheral edema and higher BUN. In the combined dataset, WHF was associated with an increase in the CE (hazard ratio [HR] 1.64; 95% confidence interval [CI] 1.11-2.42; p-value 0.01). However, the association between WHF and 60-day outcomes was significant in ROSE but not in DOSE (Table). The development of WHF between 48-72 hours compared with 0-24 hours or 24-48 hours was associated with improved outcomes ([HR] 0.48, 95% CI 0.27 - 0.88, p-value 0.02 and [HR] 0.45, 95% CI 0.26 - 0.78, p-value 0.004, respectively). Conclusions: A WHF definition that incorporated intensification of diuretics increased the event rate but was not associated with worse 60-day outcomes. The timing of a WHF event also had a differential association with outcomes. These data support the use of a standardized WHF definition in clinical trials.
Growth Differentiation Factor-15, Treatment with Liraglutide, and Clinical Outcomes Among Patients with Heart Failure
Abstract Aims Associations between growth differentiation factor-15 (GDF-15), cardiovascular outcomes, and exercise capacity among patients with a recent hospitalization for heart failure (HHF) and heart failure with reduced ejection fraction (HFrEF) are unknown. We utilized data from the ‘Functional Impact of GLP-1 for Heart Failure Treatment’ (FIGHT) study to address these knowledge gaps. Methods and results FIGHT was a randomized clinical trial testing the effect of liraglutide (vs. placebo) among 300 participants with HFrEF and a recent HHF. Multivariable regression models evaluated associations between baseline GDF-15 and change in GDF-15 (per 1000 pg/mL increase from baseline to 30 days) with clinical outcomes (at 180 days) and declines in exercise capacity (6 min walk distance ≥ 45 m). At baseline (n = 249), median GDF-15 value was 3221 pg/mL (interquartile range 1938–5511 pg/mL). Participants in the highest tertile of baseline GDF-15 were more likely to be male and have more co-morbidities. After adjustment, an increase in GDF-15 over 30 days was associated with higher risk of death or HHF [hazard ratio 1.35, 95% confidence interval (CI) 1.11–1.64]. In addition, higher baseline GDF-15 (per 1000 pg/mL until 6000 pg/mL) and an increase in GDF-15 over 30 days were associated with declining 6 min walk distance (odds ratio 1.26, 95% CI 1.02–1.55 and odds ratio 1.37, 95% CI 1.12–1.69, respectively). GDF-15 levels remained stable among participants randomized to liraglutide. Conclusions An increase in GDF-15 over 30 days among patients in HFrEF was independently associated with an increased risk of cardiovascular events and declining exercise capacity. These results support the value of longitudinal GDF-15 trajectory in informing risk of heart failure disease progression.
Implications of Peripheral Oedema in Heart Failure with Preserved Ejection Fraction: A Heart Failure Network Analysis
Abstract Aims Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous condition, and tissue congestion manifested by oedema is not present in all patients. We compared clinical characteristics, exercise capacity, and outcomes in patients with HFpEF with and without oedema. Methods and results This study was a post hoc analysis of pooled data of patients with left ventricular ejection fraction of ≥50% enrolled in the DOSE, CARRESS-HF, RELAX, ATHENA, ROSE, INDIE, and NEAT trials. Patients were dichotomized by the severity of oedema. Cox proportional hazard regression and generalized linear regression models were used to assess associations between oedema, symptoms, and clinical outcomes. The ambulatory cohort included 393 patients (228 with and 165 without oedema), and the hospitalized cohort included 338 patients (249 with ≥moderate oedema and 89 with mild or none). Among ambulatory patients, patients with oedema had a higher body mass index (35.2 kg/m2 [inter-quartile range, IQR 30.5, 41.6] vs. 31.6 kg/m2 [IQR 27.9, 36.3], P < 0.001), greater burden of co-morbidities, higher intravascular pressures estimated on physical examination (elevated jugular venous pressure: 50% vs. 24.7%, P < 0.001), poorer renal function (creatinine: 1.2 mg/dL [IQR 0.9, 1.5] vs. 1 mg/dL [IQR 0.8, 1.3], P = 0.003), and lower peak VO2 (adjusted mean difference −1.04 mL/kg/min, 95% confidence interval [−1.71, −0.37], P < 0.003). Among hospitalized patients, despite greater in-hospital fluid/weight loss in the ≥moderate oedema group, there was no difference in the improvement in dyspnoea by the visual analogue scale or well-being visual analogue scale from baseline to 3–4 days and no statistically significant difference in the rate of 60 day rehospitalization/death (adjusted hazard ratio 1.44, 95% confidence interval [0.87, 2.39], P = 0.156). Conclusions Patients with HFpEF and oedema display higher body mass, greater burden of co-morbidities, and more severe exercise intolerance, but clinical responses to treatment appear similar. Further research is required to better understand the nature of volume distribution in different HFpEF phenotypes.
Effect of Praliciguat on Peak Rate of Oxygen Consumption in Patients With Heart Failure With Preserved Ejection Fraction
Background: Comorbidity-driven microvascular inflammation is posited as a unifying pathophysiologic mechanism for heart failure with preserved ejection fraction (HFpEF). Obesity is proinflammatory and common in HFpEF. We hypothesized that unique obesity-inflammation HFpEF phenotypes exist and are associated with differences in clinical features, fibrosis biomarkers, and functional performance. Methods: Patients (n=301) from 3 HFpEF clinical trials were studied. Unsupervised machine learning (hierarchical clustering) with obese status and 13 inflammatory biomarkers as input variables was performed. Associations of clusters with HFpEF severity and fibrosis biomarkers (PIIINP [procollagen III N-terminal peptide], CITP [C-telopeptide for type I collagen], IGFBP7 [insulin-like growth factor-binding protein-7], and GAL-3 [galectin-3]) were assessed. Results: Hierarchical clustering revealed 3 phenotypes: pan-inflammatory (n=129; 64% obese), noninflammatory (n=83; 55% obese), and obese high CRP (C-reactive protein; n=89; 98% obese). The pan-inflammatory phenotype had more comorbidities and heart failure hospitalizations; higher left atrial volume, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and fibrosis biomarkers; and lower glomerular filtration rate, peak oxygen consumption, 6-minute walk distance, and active hours/day ( P <0.05 for all). The noninflammatory phenotype had the most favorable values for all measures. The obese high CRP phenotype resembled the noninflammatory phenotype except for isolated elevation of CRP and lower functional performance. Hierarchical cluster assignment was independent of CRP genotype combinations that alter CRP levels and more biologically plausible than other clustering approaches. Multiple traditional analytic techniques confirmed and extended the hierarchical clustering findings. Conclusions: Unique obesity-inflammation phenotypes exist in HFpEF and are associated with differences in comorbidity burden, HFpEF severity, and fibrosis. These data support comorbidity-driven microvascular inflammation as a pathophysiologic mechanism for many but not all HFpEF patients.