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Updated: Feb 13, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Percutaneous Left Atrial Appendage Closure with WATCHMAN™ device: peri-procedural and mid-term outcomes from the
Patrizio Mazzone1, Giuseppe D'Angelo2, Damiano Regazzoli2
1Arrhythmology and Electrophysiology Unit, Cardio-Thoracic-Vascular Department, IRCCS San Raffaele Scientific Institute, Via Olgettina 60, 20132, Milan, Italy. mazzone.patrizio@hsr.it.
Insights
The WATCHMAN device offers a safe and effective alternative to oral anticoagulation for stroke prevention in atrial fibrillation patients. Mid-term follow-up shows low rates of death, stroke, and bleeding events.
Area of Science:
- Cardiology
- Medical Devices
- Interventional Cardiology
Background:
- Atrial fibrillation (AF) patients often require oral anticoagulation (OAC) for stroke prevention.
- The WATCHMAN device provides an alternative to OAC for Left Atrial Appendage Occlusion (LAAO).
- Clinical adoption of LAAO signifies a shift in AF management strategies.
Purpose of the Study:
- To evaluate the safety and efficacy of the WATCHMAN device for LAAO.
- To assess clinical outcomes at mid-term follow-up in a real-world patient cohort.
- To analyze the procedural success and complication rates associated with LAAO.
Main Methods:
- Observational, multicenter TRAPS Registry involving four Italian centers.
- Inclusion of consecutive patients undergoing LAAO with the WATCHMAN device.
- Collection of clinical, demographic, procedural, and mid-term follow-up data.
Main Results:
- Successful implantation in 150/151 patients; minimal peri-procedural leakage.
- Low intra-procedural event rate (3.3%); one case of device embolization without sequelae.
- Median follow-up of 16 months: annual rates of all-cause stroke (2.2%), TIA (1.3%), and major bleeding (0.4%).
Conclusions:
- LAAO with the WATCHMAN device is a safe and effective stroke prevention strategy in non-valvular AF.
- Low rates of death, thromboembolic events, and bleeding observed over mid-term follow-up.
- Findings confirmed in an unselected patient group, including those variably eligible for OAC.
Purpose:
The WATCHMAN device for Left Atrial Appendage Occlusion (LAAO) has proven to be an effective alternative to oral anticoagulation (OAC) in patients with atrial fibrillation (AF), and has now been adopted in clinical practice. In the present study, we analyzed the safety and efficacy profile of the LAAO procedure at mid-term follow-up.
Methods:
The TRAPS Registry is an observational, multicenter registry involving four Italian centers. Consecutive patients who had undergone LAAO with WATCHMAN device were enrolled. Clinical, demographic, and procedural data were collected at the time of implantation, and follow-up data were collected to assess the clinical outcome.
Results:
A total of 151 patients were included in the Registry from May 2012 to October 2015. Implantation of the device was successful in 150/151 patients, with no or minimal (< 5 mm) leakage as assessed by peri-procedural transesophageal echo. In the remaining patient, early device embolization was reported, with no sequelae. Overall, intra-procedural events were reported in 5 (3.3%) patients. During a median follow-up of 16 months (25th and 75th percentile, 10-25), 5 patients died of any cause. The annual rate of all-cause stroke was 2.2% (95% CI, 0.7-5.1), the rate of transient ischemic attack was 1.3% (95% CI, 0.3-3.8), and that of major bleeding 0.4% (95% CI, 0.01-2.4).
Conclusions:
LAAO for stroke prevention was safely and effectively achieved by implantation of the WATCHMAN device in patients with non-valvular AF. Moreover, regardless of the risk profile of the population, we observed low rates of death and thromboembolic and bleeding events over a median follow-up of 16 months. These findings were obtained in an unselected group of consecutive patients who were variably eligible for chronic OAC therapy.
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