Incidence of pericardial effusion after left atrial appendage closure: The impact of underlying heart rhythm-Data from the EWOLUTION study

Introduction: Pericardial effusion/tamponade (PE/PT) is a rare but serious complication following left atrial appendage closure (LAAC). It may be speculated that LAA contraction during sinus rhythm (SR) exerts mechanical force on the device that eventually leads to PE. We sought to determine the incidence and predictors of PE following LAAC using Watchman with special emphasis on the underlying heart rhythm during implant. Methods and results: From 47 centers in 13 European countries 1,020 patients underwent LAAC and data on baseline rhythm were available from 1,010 patients (mean age 73 +/- 9 years, 60% male, median CHA2DS2-VASc = 4). Data were collected via electronic case report forms. A Cox proportional hazard model was calculated adjusting for multiple variables: age, gender, number of recaptures, and device oversizing. During implant, 41% and 59% of patients were in SR and atrial fibrillation (AF), respectively. PE/PT rate was significantly lower in patients implanted during AF at day 30 postimplant (n = 1; 0.2% vs. n = 6; 1.5%; P = 0.02). No PE requiring intervention occurred in the AF group compared to 5 events (1.2%) in the SR group (P = 0.01). While univariate analysis identified SR and gender as predictors for PE/tamponade, multivariate analysis only showed a statistical trend for both variables. Conclusion: The overall incidence of PE/PT was very low after LAAC using Watchman. Although SR was not identified as an independent predictor of PE/PT, all events requiring intervention occurred in patients with SR. It may be advisable to perform an extended echocardiographic follow-up in that patient population.