Interatrial Shunt Treatment for Heart Failure: The Randomized RELIEVE-HF Trial

An interatrial shunt may provide an autoregulatory mechanism to decrease left atrial pressure and improve heart failure (HF) symptoms and prognosis. Patients with symptomatic HF with any left ventricular ejection fraction (LVEF) were randomized 1:1 to transcatheter shunt implantation versus a placebo procedure, stratified by reduced (≤40%) versus preserved (>40%) LVEF. The primary safety outcome was a composite of device-related or procedure-related major adverse cardiovascular or neurological events at 30 days compared with a prespecified performance goal of 11%. The primary effectiveness outcome was the hierarchical composite ranking of all-cause death, cardiac transplantation or left ventricular assist device implantation, HF hospitalization, outpatient worsening HF events, and change in quality of life from baseline measured by the Kansas City Cardiomyopathy Questionnaire overall summary score through maximum 2-year follow-up, assessed when the last enrolled patient reached 1-year follow-up, expressed as the win ratio. Prespecified hypothesis-generating analyses were performed on patients with reduced and preserved LVEF. Between October 24, 2018, and October 19, 2022, 508 patients were randomized at 94 sites in 11 countries to interatrial shunt treatment (n=250) or a placebo procedure (n=258). Median (25th and 75th percentiles) age was 73.0 years (66.0, 79.0), and 189 patients (37.2%) were women. Median LVEF was reduced (≤40%) in 206 patients (40.6%) and preserved (>40%) in 302 patients (59.4%). No primary safety events occurred after shunt implantation (upper 97.5% confidence limit, 1.5%;