Impact of Autonomic Regulation Therapy in Patients with Heart Failure: ANTHEM-HFrEF Pivotal Study Design.

BACKGROUND: The ANTHEM-HFrEF (Autonomic Regulation Therapy to Enhance Myocardial Function and Reduce Progression of Heart Failure with Reduced Ejection Fraction) pivotal study is an adaptive, open-label, randomized, controlled study evaluating whether autonomic regulation therapy will benefit patients with advanced HFrEF. While early-phase studies have supported potential use of vagus nerve stimulation to deliver autonomic regulation therapy for HFrEF, results of larger clinical trials have been inconsistent. The ANTHEM-HFrEF study uses a novel design, with adaptive sample size selection, evaluating effects on morbidity and mortality as well as symptoms and function. METHODS: The ANTHEM-HFrEF study will randomize patients (2:1) to autonomic regulation therapy plus guideline-directed medical therapy, or guideline-directed medical therapy alone. The morbidity and mortality trial utilizes a conventional frequentist approach for analysis of the primary outcome end point-reduction in the composite of cardiovascular death or first HF hospitalization-and a Bayesian adaptive approach toward sample size selection. Embedded within the ANTHEM-HFrEF study is a second trial evaluating improvement in symptoms and function. Symptom/function success will require meeting 2 risk-related conditions (trend for reduced cardiovascular death/HF hospitalization and sufficient freedom from device-related serious adverse events) and 3 efficacy end point components (changes in left ventricular EF, 6-minute walk distance, and Kansas City Cardiomyopathy Questionnaire overall score). CONCLUSIONS: Vagus nerve stimulation remains a promising, yet unproven treatment in HFrEF. A successful ANTHEM-HFrEF pivotal study would provide an important advance in HFrEF treatment and offer a model for expediting evaluation of new therapies. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT03425422.

Short-Term Effects of Tolvaptan in Patients With Acute Heart Failure and Volume Overload.

BACKGROUND: In patients with acute heart failure (AHF), dyspnea relief is the most immediate goal. Renal dysfunction, diuretic resistance, and hyponatremia represent treatment impediments. OBJECTIVES: It was hypothesized that the addition of tolvaptan to a background diuretic improved dyspnea early in patients selected for an enhanced vasopressin antagonism response. METHODS: In a double-blind trial, patients were randomized to tolvaptan 30 mg/day or placebo. Study entry required hospitalization within the previous 36 h, active dyspnea, and any of the following: 1) estimated glomerular filtration rate <60 ml/min/1.73 m2; 2) hyponatremia; or 3) diuretic resistance (urine output ≤125 ml/h following intravenous furosemide ≥40 mg). The primary endpoint was a 7-point change in self-assessed dyspnea at 8 and 16 h, using a novel standardized approach. RESULTS: We randomized 250 patients. There was no difference in the primary endpoint of day 1 dyspnea reduction, despite significantly greater weight reduction with tolvaptan (-2.4 ± 2.1 kg vs. -0.9 ± 1.8 kg; p < 0.001). At day 3, dyspnea reduction was greater with tolvaptan (p = 0.01). There were 2 significant treatment-by-subgroup interactions: patients without elevated jugular venous pressure and those without ascites showed directional favorability of tolvaptan over placebo for the primary endpoint compared with patients with these findings. CONCLUSIONS: Despite rapid and persistent weight loss with tolvaptan compared with placebo, in patients with AHF who were selected for greater potential benefit from vasopressin receptor inhibition, tolvaptan was not associated with greater early improvement in dyspnea. Apparent subsequent differences in dyspnea warrant further exploration of the temporal relationship between diuresis and dyspnea relief and a possible clinical role for tolvaptan. (Randomized, Double-Blind, Placebo Controlled Study of the Short Term Clinical Effects of Tolvaptan in Patients Hospitalized for Worsening Heart Failure With Challenging Volume Management [SECRET of CHF]; NCT01584557).

Tolvaptan in Patients Hospitalized With Acute Heart Failure: Rationale and Design of the TACTICS and the SECRET of CHF Trials.

Congestion is a primary reason for hospitalization in patients with acute heart failure (AHF). Despite inpatient diuretics and vasodilators targeting decongestion, persistent congestion is present in many AHF patients at discharge and more severe congestion is associated with increased morbidity and mortality. Moreover, hospitalized AHF patients may have renal insufficiency, hyponatremia, or an inadequate response to traditional diuretic therapy despite dose escalation. Current alternative treatment strategies to relieve congestion, such as ultrafiltration, may also result in renal dysfunction to a greater extent than medical therapy in certain AHF populations. Truly novel approaches to volume management would be advantageous to improve dyspnea and clinical outcomes while minimizing the risks of worsening renal function and electrolyte abnormalities. One effective new strategy may be utilization of aquaretic vasopressin antagonists. A member of this class, the oral vasopressin-2 receptor antagonist tolvaptan, provides benefits related to decongestion and symptom relief in AHF patients. Tolvaptan may allow for less intensification of loop diuretic therapy and a lower incidence of worsening renal function during decongestion. In this article, we summarize evidence for decongestion benefits with tolvaptan in AHF and describe the design of the Targeting Acute Congestion With Tolvaptan in Congestive Heart Failure Study (TACTICS) and Study to Evaluate Challenging Responses to Therapy in Congestive Heart Failure (SECRET of CHF) trials.

Causes of death and rehospitalization in patients hospitalized with worsening heart failure and reduced left ventricular ejection fraction: results from Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) program.

BACKGROUND: The postdischarge rehospitalization and death rates are high in patients with acute heart failure (HF) syndromes despite optimization of standard therapy for chronic HF. To the best of our knowledge, there has been no systematic analysis of the causes of death and rehospitalization in this patient population. METHODS: This was a prespecified analysis of adjudicated cause-specific all-cause mortality and cardiovascular (CV) hospitalization in the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) trial, a randomized, double-blind, placebo-controlled study in patients hospitalized with worsening HF and left ventricular ejection fraction < or =40% comparing tolvaptan, an oral vasopressin receptor antagonist to placebo, in addition to standard care. RESULTS: Of the 4,133 randomized, there were 5,239 rehospitalizations and 1,080 deaths during a median of 9.9 months. Of all deaths, 41.0% were due to HF, 26.0% due to sudden cardiac death (SCD), 2.6% due to acute myocardial infarction (MI), 2.2% due to stroke, and 13.2% due to non-CV causes. Of all hospitalizations, 39.2% were non-CV, whereas 46.3% were for HF, and a minority of hospitalizations was due to stroke, MI, arrhythmia, or other CV causes. CONCLUSIONS: Despite close follow-up and evidence-based therapy within a clinical trial, rehospitalization and death remain high. Although most deaths were from HF, one quarter of patients had SCD. In addition, there were almost as many non-CV hospitalizations as HF hospitalizations. Knowledge of the causes of death and rehospitalization may be essential for proper management and early initiation of therapy.

Acute hemodynamic effects of tolvaptan, a vasopressin V2 receptor blocker, in patients with symptomatic heart failure and systolic dysfunction: an international, multicenter, randomized, placebo-controlled trial.

OBJECTIVES: This study sought to assess the acute hemodynamic effect of vasopressin V(2) receptor antagonism. BACKGROUND: In decompensated heart failure (HF), tolvaptan, a vasopressin V(2) receptor antagonist, has been shown to improve congestion. It has not yet been established whether these improvements may be associated with the hemodynamic effects of tolvaptan. METHODS: A total of 181 patients with advanced HF on standard therapy were randomized to double-blind treatment with tolvaptan at a single oral dose (15, 30, or 60 mg) or placebo. RESULTS: Tolvaptan at all doses significantly reduced pulmonary capillary wedge pressure (-6.4 +/- 4.1 mm Hg, -5.7 +/- 4.6 mm Hg, -5.7 +/- 4.3 mm Hg, and -4.2 +/- 4.6 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05 for all tolvaptan vs. placebo). Tolvaptan also reduced right atrial pressure (-4.4 +/- 6.9 mm Hg [p < 0.05], -4.3 +/- 4.0 mm Hg [p < 0.05], -3.5 +/- 3.6 mm Hg, and -3.0 +/- 3.0 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively) and pulmonary artery pressure (-5.6 +/- 4.2 mm Hg, -5.5 +/- 4.1 mm Hg, -5.2 +/- 6.1 mm Hg, and -3.0 +/- 4.7 mm Hg for the 15-mg, 30-mg, 60-mg, and placebo groups, respectively; p < 0.05). Tolvaptan increased urine output by 3 h in a dose-dependent manner (p < 0.0001), without changes in renal function. CONCLUSIONS: In patients with advanced HF, tolvaptan resulted in favorable but modest changes in filling pressures associated with a significant increase in urine output. These data provide mechanistic support for the symptomatic improvements noted with tolvaptan in patients with decompensated HF. (Heart Pressure Assessment Study With Tolvaptan to Treat Congestive Heart Failure; NCT00132886).