Surgical and transcatheter left atrial appendage closure in patients with atrial fibrillation and hypertrophic cardiomyopathy.

BACKGROUND: Patients with hypertrophic cardiomyopathy (HCM) and atrial fibrillation (AF) are at increased stroke risk in comparison to those with non-valvular AF not affected by HCM. OBJECTIVES: To investigate the role of left atrial appendage closure (LAAC) in patients with HCM and AF. METHODS AND RESULTS: We identified patients with HCM and AF using the National Readmission Dataset. Patients were stratified based on LAAC status. The primary efficacy outcome was a composite of ischaemic and haemorrhagic stroke, TIA, and all-cause mortality. The primary safety outcome was a composite of major bleeding and pericardial complications. Patients were matched using inverse probability of treatment weighting. Cox-proportional hazard regression was applied to calculate the hazard ratio (HR) with a 95% confidence interval (CI) on matched cohorts. We identified 71 980 patients with HCM and AF. 1351 (1.9%) patients underwent LAAC. Two hundred and eighty-seven (21.2%) underwent transcatheter LAAC. LAAC was associated with a lower risk of the primary efficacy outcome (2.5% vs. 5.4%, HR: 0.38; 95% CI: 0.17-0.88; P = 0.024), the primary safety outcome (2.9% vs. 6.8%, HR: 0.39; 95% CI: 0.23-0.66, P = 0.001), and reduced major bleeding. The LAAC group trended towards a lower risk of ischaemic stroke and all-cause mortality. CONCLUSION: Surgical and transcatheter LAAC was associated with a lower risk of haemorrhagic stroke and major bleeding.