Leadless Ultrasound-Based Cardiac Resynchronization System in Heart Failure.
Singh JP., Rinaldi CA., Sanders P., Kubo SH., James S., Niazi IK., Betts T., Butter C., Okabe T., Cunnane R., Aziz E., Biffi M., Zaidi A., Alison J., Defaye P., Aurrichio A., Gold MR., Lindenfeld J., Rogers T., Walsh MN., SOLVE-CRT Investigators None.
IMPORTANCE: Approximately 40% of patients with heart failure (HF) who are eligible for cardiac resynchronization therapy (CRT) either fail to respond or are untreatable due to anatomical constraints. OBJECTIVE: To assess the safety and efficacy of a novel, leadless, left ventricular (LV) endocardial pacing system for patients at high risk for a CRT upgrade or whose coronary sinus (CS) lead placement/pacing with a conventional CRT system failed. DESIGN, SETTING, AND PARTICIPANTS: The SOLVE-CRT study was a prospective multicenter trial, enrolling January 2018 through September 2022, with follow-up in March 2023. Data were analyzed from DATE MONTH, YEAR, through DATE MONTH, YEAR. The trial combined data from an initial randomized, double-blind study (n = 108) and a subsequent single-arm part (n = 75). It took place at 36 centers across Australia, Europe, and the US. Participants were nonresponders, previously untreatable (PU), or high-risk upgrades (HRU). All participants contributed to the safety analysis. The primary efficacy analysis (n = 100) included 75 PU-HRU patients from the single-arm part and 25 PU-HRU patients from the randomized treatment arm. INTERVENTIONS: Patients were implanted with the WiSE CRT System (EBR Systems) consisting of a leadless LV endocardial pacing electrode stimulated with ultrasound energy delivered by a subcutaneously implanted transmitter and battery. MAIN OUTCOMES AND MEASURES: The primary safety end point was freedom from type I complications. The primary efficacy end point was a reduction in mean LV end systolic volume (LVESV). RESULTS: The study included 183 participants; mean age was 68.1 (SD, 10.3) years and 141 were male (77%). The trial was terminated at an interim analysis for meeting prespecified stopping criteria. In the safety population, patients were either New York Heart Association Class II (34.6%) or III (65.4%). The primary efficacy end point was met with a 16.4% (95% CI, -21.0% to -11.7%) reduction in mean LVESV (P = .003). The primary safety end point was met with an 80.9% rate of freedom from type I complications (P