Pericardial Effusion After Left Atrial Appendage Closure

Pericardial effusion (PE) is the most common serious left atrial appendage closure (LAAC) complication, but its mechanisms, time course, and prognostic impact are poorly understood. This study sought to assess the frequency, timing, predictors and clinical impact of PE after LAAC. Data on consecutive patients undergoing percutaneous LAAC between 2009 and 2022 were prospectively collected including the 1-year follow-up. Both single (Watchman 2.5/FLX, Boston Scientific) and double (Amplatzer Cardiac Plug or Amulet, St. Jude Medical/Abbott) LAAC devices were used. An imaging core laboratory adjudicated the PEs and categorized them as early (≤7 days) and late (8-365 days). Logistic regression analysis was used to identify predictors of early and overall PE. Of 1,023 attempted LAAC procedures, PE was observed in 44 (4.3%) patients; PE was categorized as early in 34 (3.3%) and late in 10 (0.9%) patients. The majority of PEs occurred within 6 hours after LAAC (n = 25, 56.8%) and were clinically relevant (n = 28, 63.6%). Independent predictors of early PE were double-closure left atrial appendage devices (adjusted OR: 8.20; 95% CI: 1.09-61.69), female sex (adjusted OR: 3.41; 95% CI: 1.50-7.73), the use of oral anticoagulation (OAC) at baseline (adjusted OR: 2.60; 95% CI: 1.11-6.09), and advanced age (adjusted OR: 1.07; 95% CI: 1.01-1.23), whereas female sex and OAC at baseline remained independent predictors of overall PE. In this large LAAC registry, PE was observed in less than 1 in 20 patients and usually occurred within 6 hours after procedure. The majority of early PEs were clinically relevant and occurred in the Amplatzer Cardiac Plug/Amulet procedures. Independent predictors included the use of double-closure devices, female sex, OAC at baseline, and advanced age. (LAAC-registry: Clinical Outcome After Echocardiography-guided LAA-closure; NCT04628078)