Related Experiment Video
Updated: Feb 11, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Incidence of pericardial effusion after left atrial appendage closure: The impact of underlying heart rhythm-Data
Boris Schmidt1, Timothy R Betts2, Horst Sievert3
1Cardioangiologisches Centrum Bethanien (CCB), Frankfurt Am Main, Germany.
Insights
Pericardial effusion/tamponade is rare after Watchman left atrial appendage closure (LAAC). Patients implanted during atrial fibrillation had fewer events than those in sinus rhythm, suggesting rhythm management may impact safety.
Area of Science:
- Cardiology
- Medical Devices
- Interventional Cardiology
Background:
- Pericardial effusion/tamponade (PE/PT) is a rare but serious complication after left atrial appendage closure (LAAC).
- The mechanical forces of left atrial appendage (LAA) contraction during sinus rhythm (SR) may contribute to PE/PT.
- Predictors of PE/PT following LAAC require further investigation, particularly the role of heart rhythm during implantation.
Purpose of the Study:
- To determine the incidence and predictors of PE/PT after LAAC using the Watchman device.
- To investigate the impact of the underlying heart rhythm (SR vs. atrial fibrillation) during implantation on PE/PT development.
Main Methods:
- A multicenter study involving 1,010 patients undergoing LAAC with the Watchman device.
- Data collected via electronic case report forms, including baseline rhythm and post-implant complications.
- Cox proportional hazard model used to analyze predictors of PE/PT, adjusting for age, gender, recaptures, and device oversizing.
Main Results:
- The overall incidence of PE/PT was low (1.5% in SR group, 0.2% in AF group).
- PE/PT rate was significantly lower in patients implanted during atrial fibrillation (AF) compared to sinus rhythm (SR) (P=0.02).
- All PE events requiring intervention occurred in patients implanted during SR (P=0.01).
Conclusions:
- The incidence of PE/PT following Watchman LAAC is very low.
- While SR was not an independent predictor in multivariate analysis, all intervention-requiring PE/PT events occurred in SR patients.
- Extended echocardiographic follow-up may be advisable for patients implanted in SR.
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.
Related Concept Videos
Disturbances in Heart Rhythm
Arrhythmias are categorized by their speed, rhythm, and origin. A slow heart...
Behavior of Gas Molecules: Molecular Diffusion, Mean Free Path, and Effusion
Prevalence and Incidence
Prevalence indicates the proportion of individuals in a population who have a specific disease or health...
Cardiac Catheterization III: Left Heart Catheterization
Surface Appendages of Archaea
Pleural Effusion I: Introduction
There are two main types of pleural effusion: transudative and exudative. They are differentiated using Light's...

