Related Experiment Video
Updated: May 11, 2026
The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Primary Outcome Evaluation of a Next-Generation Left Atrial Appendage Closure Device: Results From the PINNACLE FLX
Saibal Kar1,2, Shephal K Doshi3, Ashish Sadhu4
1Los Robles Regional Medical Center, Thousand Oaks, CA (S.K.).
Insights
The WATCHMAN FLX device effectively closes the left atrial appendage, offering a safe alternative to blood thinners for atrial fibrillation patients. This study confirms its high success rate and low complication risk.
Area of Science:
- Cardiology
- Medical Devices
- Thrombosis Prevention
Background:
- Left atrial appendage (LAA) occlusion is an alternative to oral anticoagulation for reducing thromboembolic risk in nonvalvular atrial fibrillation (AF).
- The WATCHMAN device, approved in 2015, is the primary LAA closure device used in the US.
- The PINNACLE FLX study investigated the next-generation WATCHMAN FLX device.
Purpose of the Study:
- To evaluate the safety and effectiveness of the WATCHMAN FLX LAA closure device.
- To assess its suitability as a non-pharmaceutical alternative for patients with nonvalvular AF.
- To determine if the device meets predefined safety and efficacy performance goals.
Main Methods:
- Prospective, nonrandomized, multicenter US FDA study.
- Primary safety endpoint: composite of death, stroke, systemic embolism, or device/procedure-related events within 7 days post-procedure.
- Primary effectiveness endpoint: successful LAA closure (peri-device flow ≤5 mm) assessed by echocardiography at 12 months.
Main Results:
- 400 patients enrolled; mean age 73.8 years, mean CHA₂DS₂-VASc score 4.2.
- Primary safety endpoint incidence was 0.5% (performance goal 4.2%), P<0.0001.
- Primary effectiveness endpoint (LAA closure) incidence was 100% (performance goal 97.0%), P<0.0001.
Conclusions:
- Next-generation LAA closure with the WATCHMAN FLX device demonstrated a low incidence of adverse events.
- High rates of successful anatomic LAA closure were observed.
- The device met its predefined safety and effectiveness performance goals.
Background:
Left atrial appendage (LAA) occlusion provides an alternative to oral anticoagulation for thromboembolic risk reduction in patients with nonvalvular atrial fibrillation. Since regulatory approval in 2015, the WATCHMAN device has been the only LAA closure device available for clinical use in the United States. The PINNACLE FLX study (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the Watchman FLX LAA Closure Technology) evaluated the safety and effectiveness of the next-generation WATCHMAN FLX LAA closure device in patients with nonvalvular atrial fibrillation in whom oral anticoagulation is indicated, but who have an appropriate rationale to seek a nonpharmaceutical alternative.
Methods:
This was a prospective, nonrandomized, multicenter US Food and Drug Administration study. The primary safety end point was the occurrence of one of the following events within 7 days after the procedure or by hospital discharge, whichever was later: death, ischemic stroke, systemic embolism, or device- or procedure-related events requiring cardiac surgery. The primary effectiveness end point was the incidence of effective LAA closure (peri-device flow ≤5 mm), as assessed by the echocardiography core laboratory at 12-month follow-up.
Results:
A total of 400 patients were enrolled. The mean age was 73.8±8.6 years and the mean CHA2DS2-VASc score was 4.2±1.5. The incidence of the primary safety end point was 0.5% with a 1-sided 95% upper CI of 1.6%, meeting the performance goal of 4.2% (P<0.0001). The incidence of the primary effectiveness end point was 100%, with a 1-sided 95% lower CI of 99.1%, again meeting the performance goal of 97.0% (P<0.0001). Device-related thrombus was reported in 7 patients, no patients experienced pericardial effusion requiring open cardiac surgery, and there were no device embolizations.
Conclusions:
LAA closure with this next-generation LAA closure device was associated with a low incidence of adverse events and a high incidence of anatomic closure. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02702271.
Related Concept Videos
01:24Cardiac Catheterization III: Left Heart Catheterization
01:23Mitral Stenosis II: Clinical features and Diagnostic Tests
01:30Acute Coronary Syndrome III: Diagnostic Studies