Lessons learned from a clinical trial: Design, rationale, and insights from The Cardiovascular Improvements with Minute Ventilation-targeted Adaptive Sero-Ventilation (ASV) Therapy in Heart Failure (CAT-HF) Study

Objective: The CAT-HF Study was designed to evaluate the safety and efficacy of minute ventilation-targeted adaptive servo-ventilation (MV-ASV) during sleep in addition to optimized medical therapy (active therapy) versus optimized medical therapy alone (usual care) at 6 months, initiated in patients after hospitalization for acute decompensated heart failure (ADHF). This paper outlines the rationale, design and information learned at the time of study discontinuation. Background: Sleep disordered breathing (SDB) is common in heart failure patients and is associated with worse outcomes in this patient population. Based on a belief that MV-ASV was safe in stable HF patients, CAT-HF was designed to examine whether MV-ASV improved outcomes in hospitalized HF patients During the course of CAT-HF, new results from SERVE-HF indicated that ASV therapy may be harmful in patients with left ventricular ejection fractions (LVEF). ≤ 45% and central sleep apnea, a subgroup of patients enrolled in CAT-HF. Methods: CAT-HF was a prospective, randomized, controlled, multicenter clinical trial (NCT: 01953874) in HF patients with either reduced or preserved ejection fraction and an Apnea-Hypopnea Index ≥ 15 events per hour randomized to usual care or active treatment in a 1:1 ratio. 215 patients were intended to be randomized following a hospitalization for ADHF. At the time of discontinuation, 126 patients were randomized. The primary endpoint is a global rank composite endpoint of death, CV hospitalizations, and Six minute walk distance (6MWD). Secondary endpoints will include changes in functional parameters, biomarkers, quality of life (QOL), sleep, and breathing. Conclusions: The CAT-HF study was designed to assess the efficacy and safety of MV ASV treatment in patients after hospitalization for ADHF, but was stopped early due to safety concerns in HF patients with (LVEF). ≤ 45% and predominant central sleep apnea.