Brian Claggett

Spironolactone for Heart Failure with Preserved Ejection Fraction

BACKGROUND Mineralocorticoid-receptor antagonists improve the prognosis for patients with heart failure and a reduced left ventricular ejection fraction. We evaluated the effects of spironolactone in patients with heart failure and a preserved left ventricular ejection fraction. METHODS In this randomized, double-blind trial, we assigned 3445 patients with symptomatic heart failure and a left ventricular ejection fraction of 45% or more to receive either spironolactone (15 to 45 mg daily) or placebo. The primary outcome was a composite of death from cardiovascular causes, aborted cardiac arrest, or hospitalization for the management of heart failure. RESULTS With a mean follow-up of 3.3 years, the primary outcome occurred in 320 of 1722 patients in the spironolactone group (18.6%) and 351 of 1723 patients in the placebo group (20.4%) (hazard ratio, 0.89; 95% confidence interval [CI], 0.77 to 1.04; P=0.14). Of the components of the primary outcome, only hospitalization for heart failure had a significantly lower incidence in the spironolactone group than in the placebo group (206 patients [12.0%] vs. 245 patients [14.2%]; hazard ratio, 0.83; 95% CI, 0.69 to 0.99, P=0.04). Neither total deaths nor hospitalizations for any reason were significantly reduced by spironolactone. Treatment with spironolactone was associated with increased serum creatinine levels and a doubling of the rate of hyperkalemia (18.7%, vs. 9.1% in the placebo group) but reduced hypokalemia. With frequent monitoring, there were no significant differences in the incidence of serious adverse events, a serum creatinine level of 3.0 mg per deciliter (265 μmol per liter) or higher, or dialysis. CONCLUSIONS In patients with heart failure and a preserved ejection fraction, treatment with spironolactone did not significantly reduce the incidence of the primary composite outcome of death from cardiovascular causes, aborted cardiac arrest, or hospitalization for the management of heart failure. (Funded by the National Heart, Lung, and Blood Institute; TOPCAT ClinicalTrials.gov number, NCT00094302.).

Lixisenatide in Patients with Type 2 Diabetes and Acute Coronary Syndrome.

BACKGROUND Cardiovascular morbidity and mortality are higher among patients with type 2 diabetes, particularly those with concomitant cardiovascular diseases, than in most other populations. We assessed the effects of lixisenatide, a glucagon-like peptide 1-receptor agonist, on cardiovascular outcomes in patients with type 2 diabetes who had had a recent acute coronary event. METHODS We randomly assigned patients with type 2 diabetes who had had a myocardial infarction or who had been hospitalized for unstable angina within the previous 180 days to receive lixisenatide or placebo in addition to locally determined standards of care. The trial was designed with adequate statistical power to assess whether lixisenatide was noninferior as well as superior to placebo, as defined by an upper boundary of the 95% confidence interval for the hazard ratio of less than 1.3 and 1.0, respectively, for the primary composite end point of cardiovascular death, myocardial infarction, stroke, or hospitalization for unstable angina. RESULTS The 6068 patients who underwent randomization were followed for a median of 25 months. A primary end-point event occurred in 406 patients (13.4%) in the lixisenatide group and in 399 (13.2%) in the placebo group (hazard ratio, 1.02; 95% confidence interval [CI], 0.89 to 1.17), which showed the noninferiority of lixisenatide to placebo (P<0.001) but did not show superiority (P=0.81). There were no significant between-group differences in the rate of hospitalization for heart failure (hazard ratio in the lixisenatide group, 0.96; 95% CI, 0.75 to 1.23) or the rate of death (hazard ratio, 0.94; 95% CI, 0.78 to 1.13). Lixisenatide was not associated with a higher rate of serious adverse events or severe hypoglycemia, pancreatitis, pancreatic neoplasms, or allergic reactions than was placebo. CONCLUSIONS In patients with type 2 diabetes and a recent acute coronary syndrome, the addition of lixisenatide to usual care did not significantly alter the rate of major cardiovascular events or other serious adverse events. (Funded by Sanofi; ELIXA ClinicalTrials.gov number, NCT01147250.).

Regional Variation in Patients and Outcomes in the Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) Trial

Background— Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) patients with heart failure and preserved left ventricular ejection fraction assigned to spironolactone did not achieve a significant reduction in the primary composite outcome (time to cardiovascular death, aborted cardiac arrest, or hospitalization for management of heart failure) compared with patients receiving placebo. In a post hoc analysis, an ≈4-fold difference was identified in this composite event rate between the 1678 patients randomized from Russia and Georgia compared with the 1767 enrolled from the United States, Canada, Brazil, and Argentina (the Americas). Methods and Results— To better understand this regional difference in clinical outcomes, demographic characteristics of these populations and their responses to spironolactone were explored. Patients from Russia/Georgia were younger, had less atrial fibrillation and diabetes mellitus, but were more likely to have had prior myocardial infarction or a hospitalization for heart failure. Russia/Georgia patients also had lower left ventricular ejection fraction and creatinine but higher diastolic blood pressure (all P<0.001). Hyperkalemia and doubling of creatinine were more likely and hypokalemia was less likely in patients receiving spironolactone in the Americas with no significant treatment effects in Russia/Georgia. All clinical event rates were markedly lower in Russia/Georgia, and there was no detectable impact of spironolactone on any outcomes. In contrast, in the Americas, the rates of the primary outcome, cardiovascular death, and hospitalization for heart failure were significantly reduced by spironolactone. Conclusions— This post hoc analysis demonstrated greater potassium and creatinine changes and possible clinical benefits with spironolactone in patients with heart failure and preserved ejection fraction from the Americas. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00094302.

Moving Beyond the Hazard Ratio in Quantifying the Between-Group Difference in Survival Analysis

In a longitudinal clinical study to compare two groups, the primary end point is often the time to a specific event (eg, disease progression, death). The hazard ratio estimate is routinely used to empirically quantify the between-group difference under the assumption that the ratio of the two hazard functions is approximately constant over time. When this assumption is plausible, such a ratio estimate may capture the relative difference between two survival curves. However, the clinical meaning of such a ratio estimate is difficult, if not impossible, to interpret when the underlying proportional hazards assumption is violated (ie, the hazard ratio is not constant over time). Although this issue has been studied extensively and various alternatives to the hazard ratio estimator have been discussed in the statistical literature, such crucial information does not seem to have reached the broader community of health science researchers. In this article, we summarize several critical concerns regarding this conventional practice and discuss various well-known alternatives for quantifying the underlying differences between groups with respect to a time-to-event end point. The data from three recent cancer clinical trials, which reflect a variety of scenarios, are used throughout to illustrate our discussions. When there is not sufficient information about the profile of the between-group difference at the design stage of the study, we encourage practitioners to consider a prespecified, clinically meaningful, model-free measure for quantifying the difference and to use robust estimation procedures to draw primary inferences.

Effect of the angiotensin-receptor-neprilysin inhibitor LCZ696 compared with enalapril on mode of death in heart failure patients.

AIMS The angiotensin-receptor-neprilysin inhibitor (ARNI) LCZ696 reduced cardiovascular deaths and all-cause mortality compared with enalapril in patients with chronic heart failure in the prospective comparison of ARNI with an Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial. To more completely understand the components of this mortality benefit, we examined the effect of LCZ696 on mode of death. METHODS AND RESULTS PARADIGM-HF was a prospective, double-blind, randomized trial in 8399 patients with chronic heart failure, New York Heart Association Class II-IV symptoms, and left ventricular ejection fraction ≤40% receiving guideline-recommended medical therapy and followed for a median of 27 months. Mode of death was adjudicated by a blinded clinical endpoints committee. The majority of deaths were cardiovascular (80.9%), and the risk of cardiovascular death was significantly reduced by treatment with LCZ (hazard ratio, HR 0.80, 95% CI 0.72-0.89, P < 0.001). Among cardiovascular deaths, both sudden cardiac death (HR 0.80, 95% CI 0.68-0.94, P = 0.008) and death due to worsening heart failure (HR 0.79, 95% CI 0.64-0.98, P = 0.034) were reduced by treatment with LCZ696 compared with enalapril. Deaths attributed to other cardiovascular causes, including myocardial infarction and stroke, were infrequent and distributed evenly between treatment groups, as were non-cardiovascular deaths. CONCLUSIONS LCZ696 was superior to enalapril in reducing both sudden cardiac deaths and deaths from worsening heart failure, which accounted for the majority of cardiovascular deaths. CLINICAL TRIAL REGISTRATION https://clinicaltrials.gov/, NCT01035255.

Prognostic Importance of Impaired Systolic Function in Heart Failure With Preserved Ejection Fraction and the Impact of Spironolactone

Background— Impairment in left ventricular systolic function has been described in heart failure (HF) with preserved ejection fraction (HFpEF), but its prognostic relevance is not known. We determined whether left ventricular longitudinal strain (LS) is predictive of cardiovascular outcomes in HFpEF beyond clinical and conventional echocardiographic measures. Methods and Results— LS was assessed by 2-dimensional speckle-tracking echocardiography at baseline in 447 patients with HFpEF enrolled in the Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) trial. At a median follow-up of 2.6 years (interquartile range, 1.5–3.9 years), 115 patients experienced the primary composite outcome of cardiovascular death, HF hospitalization, or aborted cardiac arrest. Impaired LS, defined as an absolute LS <15.8%, was present in 52% of patients and was predictive of the composite outcome (adjusted hazard ratio, 2.14; 95% confidence interval, 1.26–3.66; P=0.005), cardiovascular death alone (adjusted hazard ratio, 3.20; 95% confidence interval, 1.44–7.12; P=0.004), and HF hospitalization alone (adjusted hazard ratio, 2.23; 95% confidence interval, 1.16–4.28; P=0.016) after adjustment for clinical and conventional echocardiographic variables. LS was the strongest echocardiographic predictor of the composite outcome. Exploratory analysis in a subset of 131 patients with follow-up LS assessed after 12 to 18 months demonstrated a trend toward improvement in LS associated with spironolactone in patients enrolled in the Americas but not in Russia or Georgia. Conclusions— Impaired left ventricular systolic function is a powerful predictor of HF hospitalization, cardiovascular death, or aborted cardiac arrest in HFpEF independent of clinical predictors. Impaired LS represents a novel imaging biomarker to identify patients with HFpEF at particularly high risk for cardiovascular morbidity and mortality. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00094302.

Influence of ejection fraction on outcomes and efficacy of spironolactone in patients with heart failure with preserved ejection fraction

AIMS While mineralocorticoid receptor antagonists (MRAs) have been shown to benefit patients with reduced left ventricular ejection fraction (LVEF), spironolactone did not reduce the primary endpoint of cardiovascular death, heart failure hospitalization, or aborted cardiac arrest in patients with heart failure with preserved ejection fraction (HFpEF) in the TOPCAT trial, which enrolled patients with LVEF of 45% or greater. We utilized data from TOPCAT to assess the relationship between LVEF as well as outcomes and efficacy of spironolactone. METHODS AND RESULTS We assessed differences in baseline characteristics and outcomes across LVEF categories in 3444 patients with HFpEF, and determined whether LVEF modified the treatment effect of spironolactone. Ejection fraction ranged from 44 to 85%. Patients with higher ejection fraction were older, more likely to be female, less likely to have a history of myocardial infarction, and more likely to have a history of hypertension and diabetes. The incidence of the primary endpoint and cardiovascular death was highest in patients at the lower end of the ejection fraction spectrum. Ejection fraction modified the spironolactone treatment effect, particularly in the patients enrolled in the Americas, for the primary outcome (P = 0.046) and for heart failure hospitalization (P = 0.039), with stronger estimated benefits of spironolactone at the lower end of the ejection fraction spectrum with respect to the primary endpoint (LVEF <50%: HR 0.72, 95% CI 0.50, 1.05; LVEF ≥60%: HR 0.97, 95% CI 0.76, 1.23) and heart failure hospitalization (LVEF <50%: HR 0.76, 95% CI 0.46, 1.27; LVEF ≥60%: HR 0.98, 95% CI 0.74, 1.30). CONCLUSION In patients with HFpEF enrolled in TOPCAT, patient characteristics and outcomes varied substantially by LVEF. The potential efficacy of spironolactone was greatest at the lower end of the LVEF spectrum. CLINICALTRIALSGOV NUMBER NCT00094302.

Impaired left atrial function in heart failure with preserved ejection fraction

Left atrial (LA) enlargement is present in the majority of heart failure with preserved ejection fraction (HFpEF) patients and is a marker of risk. However, the importance of LA function in HFpEF is less well understood.

Cardiac Structure and Function and Prognosis in Heart Failure With Preserved Ejection Fraction

Background—Abnormalities in cardiac structure and function in heart failure with preserved ejection fraction may help identify patients at particularly high risk for cardiovascular morbidity and mortality. Methods and Results—Cardiac structure and function were assessed by echocardiography in a blinded core laboratory at baseline in 935 patients with heart failure with preserved ejection fraction (left ventricular ejection fraction ≥45%) enrolled in the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial and related to the primary composite outcome of cardiovascular death, heart failure hospitalization, or aborted cardiac arrest, and its components. At a median follow-up of 2.9 years, 244 patients experienced the primary outcome. Left ventricular hypertrophy (adjusted hazard ratio, 1.52; 95% confidence interval, 1.16–2.00), elevated left ventricular filling pressure (E/E′; adjusted hazard ratio 1.05 per 1 integer increase; 95% confidence interval, 1.02–1.07), and higher pulmonary artery pressure assessed by the tricuspid regurgitation velocity (hazard ratio, 1.23 per 0.5 m/s increase; 95% confidence interval, 1.02–1.49) were associated with the composite outcome and heart failure hospitalization alone after adjusting for clinical and laboratory variables. The risk of adverse outcome associated with left ventricular hypertrophy was additive to the risk associated with elevated E/E′. Conclusions—Among heart failure with preserved ejection fraction patients enrolled in TOPCAT, left ventricular hypertrophy, higher left ventricular filling pressure, and higher pulmonary artery pressure were predictive of heart failure hospitalization, cardiovascular death, or aborted cardiac arrest independent of clinical and laboratory predictors. These features, both alone and in combination, identify heart failure with preserved ejection fraction patients at particularly high risk for cardiovascular morbidity and mortality. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00094302.

Incidence, Predictors, and Outcomes Related to Hypo- and Hyperkalemia in Patients With Severe Heart Failure Treated With a Mineralocorticoid Receptor Antagonist

Background—Mineralocorticoid receptor antagonists reduce morbidity and mortality in patients with heart failure but can cause hyperkalemia, which contributes to reduced use of these drugs. Hypokalemia also leads to worse outcomes in patients with heart failure and may be attenuated by mineralocorticoid receptor antagonists. Methods and Results—We assessed incidence and predictors of hyperkalemia (potassium ≥5.5 mmol/L) and hypokalemia (potassium <3.5 mmol/L) and the relationship to outcomes in 1663 patients with class III or IV heart failure and left ventricular ejection fraction <35% randomized to treatment with spironolactone 25 mg or placebo in the Randomized Aldactone Evaluation Study (RALES) trial. All-cause mortality rates and the influence of potassium levels on the effectiveness of spironolactone were assessed in a landmark analysis and in relation to time-varying potassium levels. After 1 month, mean potassium levels increased in the spironolactone group but not in the placebo group (4.54±0.49 versus 4.28±0.50 mmol/L; P<0.001) and remained elevated during the trial. Although the extremes of hypokalemia and hyperkalemia at 4 weeks were associated with increased risk of mortality in both treatment arms, participants in the spironolactone arm had lower mortality rates at all potassium levels throughout the duration of the trial. The treatment benefit of spironolactone was maintained at least until potassium exceeded 5.5 mmol/L. Conclusions—With appropriate surveillance of potassium and creatinine, the use of spironolactone was associated with less hypokalemia and improved survival in patients with severe heart failure even in the setting of moderate hyperkalemia.