Approximately half of the patients with signs and symptoms of heart failure have a left ventricular ejection fraction that is not markedly abnormal. Despite the historically initial surprise, ...heightened risks for heart failure specific major adverse events occur across the broad range of ejection fraction, including normal. The recognition of the magnitude of the problem of heart failure with preserved ejection fraction in the past 20 years has spurred an explosion of clinical investigation and growing intensity of informative outcome trials. This article addresses the historic development of this component of the heart failure syndrome, including the epidemiology, pathophysiology, and existing and planned therapeutic studies. Looking forward, more specific phenotyping and even genotyping of subpopulations should lead to improvements in outcomes from future trials.
BACKGROUND:While disease-modifying therapies exist for heart failure (HF) with reduced left ventricular ejection fraction (LVEF), few options are available for patients in the higher range of LVEF ...(>40%). Sacubitril/valsartan has been compared with a renin-angiotensin-aldosterone–system inhibitor alone in 2 similarly designed clinical trials of patients with reduced and preserved LVEF, permitting examination of its effects across the full spectrum of LVEF.
METHODS:We combined data from PARADIGM-HF (LVEF eligibility≤40%; n=8399) and PARAGON-HF (LVEF eligibility≥45%; n=4796) in a prespecified pooled analysis. We divided randomized patients into LVEF categories≤22.5% (n=1269), >22.5% to 32.5% (n=3987), >32.5% to 42.5% (n=3143), > 42.5% to 52.5% (n=1427), > 52.5% to 62.5% (n=2166), and >62.5% (n=1202). We assessed time to first cardiovascular death and HF hospitalization, its components, and total heart failure hospitlizations, all-cause mortality, and noncardiovascular mortality. Incidence rates and treatment effects were examined across categories of LVEF.
RESULTS:Among 13 195 randomized patients, we observed lower rates of cardiovascular death and HF hospitalization, but similar rates of noncardiovascular death, among patients in the highest versus the lowest groups. Overall sacubitril/valsartan was superior to renin-angiotensin-aldosterone–system inhibition for first cardiovascular death or heart failure hospitalization (Hazard Ratio HR 0.84 95% CI, 0.78–0.90), cardiovascular death (HR 0.84 95% CI, 0.76–0.92), heart failure hospitalization (HR 0.84 95% CI, 0.77–0.91), and all-cause mortality (HR 0.88 95% CI, 0.81–0.96). The effect of sacubitril/valsartan was modified by LVEF (treatment-by-continuous LVEF interaction P=0.02), and benefit appeared to be present for individuals with EF primarily below the normal range, although the treatment benefit for cardiovascular death diminished at a lower ejection fraction. We observed effect modification by LVEF on the efficacy of sacubitril/valsartan in both men and women with respect to composite total HF hospitalizations and cardiovascular death, although women derived benefit to higher ejection fractions.
CONCLUSIONS:The therapeutic effects of sacubitril/valsartan, compared with a renin-angiotensin-aldosterone–system inhibitor alone, vary by LVEF with treatment benefits, particularly for heart failure hospitalization, that appear to extend to patients with heart failure and mildly reduced ejection fraction. These therapeutic benefits appeared to extend to a higher LVEF range in women compared with men.
CLINICAL TRIAL REGISTRATION:https://www.clinicaltrials.gov. Unique identifiersNCT01920711 (PARAGON-HF), NCT01035255 (PARADIGM-HF).
Patients with heart failure with preserved ejection fraction were assigned to receive sacubitril–valsartan or valsartan. At a median of 35 months, there was no significant between-group difference in ...the composite outcome of total hospitalizations for heart failure or death from cardiovascular causes.
For a study with an event time as the endpoint, its survival function contains all the information regarding the temporal, stochastic profile of this outcome variable. The survival probability at a ...specific time point, say t, however, does not transparently capture the temporal profile of this endpoint up to t. An alternative is to use the restricted mean survival time (RMST) at time t to summarize the profile. The RMST is the mean survival time of all subjects in the study population followed up to t, and is simply the area under the survival curve up to t. The advantages of using such a quantification over the survival rate have been discussed in the setting of a fixed-time analysis. In this article, we generalize this approach by considering a curve based on the RMST over time as an alternative summary to the survival function. Inference, for instance, based on simultaneous confidence bands for a single RMST curve and also the difference between two RMST curves are proposed. The latter is informative for evaluating two groups under an equivalence or noninferiority setting, and quantifies the difference of two groups in a time scale. The proposal is illustrated with the data from two clinical trials, one from oncology and the other from cardiology.
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BFBNIB, DOBA, FSPLJ, FZAB, GIS, IJS, INZLJ, IZUM, KILJ, NLZOH, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK, ZRSKP
In a randomized trial, 5661 patients with acute myocardial infarction and a reduced left ventricular ejection fraction, pulmonary congestion, or both were assigned to receive either ...sacubitril–valsartan or ramipril. At a median of 22 months, there was no significant difference between the two groups in the incidence of death from cardiovascular causes or incident heart failure.
A noninferiority study is often used to investigate whether a treatment's efficacy or safety profile is acceptable compared with an alternative therapy regarding the time to a clinical event. The ...empirical quantification of the treatment difference for such a study is routinely based on the hazard ratio (HR) estimate. The HR, which is not a relative risk, may be difficult to interpret clinically, especially when the underlying proportional hazards assumption is violated. The precision of the HR estimate depends primarily on the number of observed events but not directly on exposure times or sample size of the study population. If the event rate is low, the study may require an impractically large number of events to ensure that the prespecified noninferiority criterion for the HR is attainable. This article discusses deficiencies in the current approach for the design and analysis of a noninferiority study. Alternative procedures are provided, which do not depend on any model assumption, to compare 2 treatments. For a noninferiority safety study, the patients' exposure times are more clinically important than the observed number of events. If the patients' exposure times are long enough to evaluate safety reliably, then these alternative procedures can effectively provide clinically interpretable evidence on safety, even with relatively few observed events. These procedures are illustrated with data from 2 studies. One explores the cardiovascular safety of a pain medicine; the second examines the cardiovascular safety of a new treatment for diabetes. These alternative strategies to evaluate safety or efficacy of an intervention lead to more meaningful interpretations of the analysis results than the conventional strategy that uses the HR estimate.
This publication describes uniform definitions for cardiovascular and stroke outcomes developed by the Standardized Data Collection for Cardiovascular Trials Initiative and the US Food and Drug ...Administration (FDA). The FDA established the Standardized Data Collection for Cardiovascular Trials Initiative in 2009 to simplify the design and conduct of clinical trials intended to support marketing applications. The writing committee recognizes that these definitions may be used in other types of clinical trials and clinical care processes where appropriate. Use of these definitions at the FDA has enhanced the ability to aggregate data within and across medical product development programs, conduct meta-analyses to evaluate cardiovascular safety, integrate data from multiple trials, and compare effectiveness of drugs and devices. Further study is needed to determine whether prospective data collection using these common definitions improves the design, conduct, and interpretability of the results of clinical trials.
Aims
We tested the hypothesis that candesartan improves outcomes in heart failure (HF) with mid‐range ejection fraction HFmrEF; ejection fraction (EF) 40–49%.
Methods and results
In 7598 patients ...enrolled in the CHARM Programme (HF across the spectrum of EF), we assessed characteristics, outcomes and treatment effect of candesartan according to EF. Patients with HFmrEF (n = 1322, 17%) were similar to those with HF with reduced EF (HFrEF; n = 4323, 57%) with respect to some characteristics, and intermediate between HFrEF and HF with preserved EF (HFpEF; n = 1953, 26%) with respect to others. Over a mean follow‐up of 2.9 years, the incidence rates for the primary outcome of cardiovascular death or HF hospitalization were 15.9, 8.5 and 8.9 per 100 patient‐years in HFrEF, HFmrEF and HFpEF. In adjusted analyses, the rates of the primary outcome declined with increasing EF up to 50%. For treatment effect, the incidence rates for the primary outcome for candesartan vs. placebo were 14.4 vs. 17.5 per 100 patient‐years in HFrEF hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.75–0.91; P < 0.001, 7.4 vs. 9.7 per 100 patient‐years in HFmrEF (HR 0.76, 95% CI 0.61–0.96; P = 0.02), and 8.6 vs. 9.1 per 100 patient‐years in HFpEF (HR 0.95, 95% CI 0.79–1.14; P = 0.57). For recurrent HF hospitalization, the incidence rate ratios were 0.68 in HFrEF (95% CI 0.58–0.80; P < 0.001), 0.48 in HFmrEF (95% CI 0.33–0.70; P < 0.001), and 0.78 in HFpEF (95% CI 0.59–1.03; P = 0.08). With EF as a continuous spline variable, candesartan significantly reduced the primary outcome until EF well over 50% and recurrent HF hospitalizations until EF well over 60%.
Conclusion
Candesartan improved outcomes in HFmrEF to a similar degree as in HFrEF.
ClinicalTrials.gov: CHARM Alternative NCT00634400, CHARM Added NCT00634309, CHARM Preserved NCT00634712
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Aims
The impact of frailty on outcomes in randomized heart failure with preserved ejection fraction (HFpEF) trials has not been previously reported. This analysis sought to characterize frailty in a ...large contemporary HFpEF clinical trial cohort and to evaluate its impact on patient relevant outcomes.
Methods and results
Using data from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial, a frailty index (FI) was constructed at baseline using 39 clinical, laboratory, and self‐reported variables. The relationship between frailty and outcomes and the role of frailty in modulating the benefits of spironolactone were examined in a subset of 1767 TOPCAT patients. For the cohort as a whole (mean age 71.5 years, 49% female), the mean FI at baseline was 0.37 ± 0.11. Four frailty classes were defined ranging from FI < 0.3 to FI ≥ 0.5. Overall, 94% of subjects were considered frail (defined as a FI > 0.21). Mean age was lowest for the most frail class (69 ± 9 years for Class 4; 73 ± 10 years for Class 1; P < 0.001). Body mass index, systolic blood pressure, and pulse pressure all increased as FI increased. Both primary and secondary outcomes increased as frailty severity increased. There was no interaction between frailty class and treatment effect of spironolactone.
Conclusions
Frailty was very common in TOPCAT HFpEF participants. Greater frailty was associated with a higher risk of cardiovascular outcomes and mortality. The benefit of spironolactone on outcomes in TOPCAT was not attenuated by frailty class.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
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