Heart failure after left atrial appendage occlusion: Insights from the LAAOS III randomized trial

AIMS: The left atrial appendage (LAA) produces natriuretic peptides and its removal or occlusion might increase the risk of heart failure (HF). We aimed to investigate the incidence of HF after LAA occlusion or removal (LAAO) in the Left Atrial Appendage Occlusion Study (LAAOS III). METHODS AND RESULTS: Patients (n = 4811) with atrial fibrillation (AF) and a CHA₂DS₂-VASc score ≥2, who were having cardiac surgery for another indication, were randomized to undergo surgical LAAO or not. We compared the composite outcome of HF-related hospitalizations and HF death between the two groups. HF assessment required clinical and radiographic evidence of HF. Analyses included a landmark analysis before and after 30 days and subgroups. Mean age was 71.2 years, 67.5% were male and 57.0% had prior HF. Over a mean follow-up of 3.8 years, 396 (8.3%) patients met the composite HF outcome: 209 (8.8%) with LAAO (n = 2379) and 187 (7.8%) without LAAO (n = 2391) (hazard ratio [HR] 1.12, 95% confidence interval [CI] 0.92-1.37, p = 0.25). There was no difference between the two groups in the first 30 days (1.6% vs. 1.1%; p = 0.12) and thereafter (7.6% vs. 7.1%; p = 0.57). Subgroups based on age, sex, body mass index, AF type, prior HF, cardiac rhythm or left ventricular ejection fraction showed consistent results. There was no difference in HF outcomes with LAAO between the cut-and-sew (HR 0.93, 95% CI 0.70-1.23, p = 0.62) versus other closure methods (HR 1.05, 95% CI 0.77-1.41, p = 0.77). CONCLUSIONS: Left atrial appendage occlusion or removal at the time of cardiac surgery does not appear to alter the risk of HF-related hospitalization or death. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT01561651.