LAAO with Watchman FLX associated with positive 1-year outcomes, real-world data confirm
![Left atrial appendage occlusion (LAAO) with the Watchman FLX device from Boston Scientific is associated with positive outcomes and limited adverse events after one year, according to new findings published in Circulation: Cardiovascular Interventions.[1] Many prior Watchman FLX studies, including PINNACLE FLX, had focused on the device’s performance in a controlled setting. The study’s authors hoped to gain a better understanding of its real-world impact by reviewing registry data from more than 97,000 U.S](/sites/default/files/styles/top_stories/public/2024-08/screenshot_2024-08-12_at_11.35.13_am.png.webp?itok=5FeQeMFj)
Left atrial appendage occlusion (LAAO) with the Watchman FLX device from Boston Scientific is associated with positive outcomes and limited adverse events after one year, according to new findings published in Circulation: Cardiovascular Interventions.[1]
Many prior Watchman FLX studies, including PINNACLE FLX, had focused on the device’s performance in a controlled setting. The study’s authors hoped to gain a better understanding of its real-world impact by reviewing registry data from more than 97,000 U.S. patients.
First author Samir Kapadia, MD, cardiovascular chair of the Miller Family Heart, Vascular and Thoracic Institute at Cleveland Clinic, colleagues tracked a total of 97,185 LAAO patients treated with the Watchman FLX device from August 2020 to September 2022. The mean patient age was 76.4 years old, 58.7% were men and the mean CHA2DS2-VASc score was 4.8. While 62.3% of patients presented with paroxysmal atrial fibrillation (AFib), 20.7% had persistent AFib, 11.6% had permanent AFib and 5.4% had long-standing persistent AFib. All patient data came from the American College of Cardiology’s NCDR LAAO Registry.
Overall, the mean procedure time in this large patient cohort was 79 minutes. The 27- and 24-mm devices were the most commonly implanted sizes by a significant margin.
The study’s primary safety endpoint—a composite of all-cause death, ischemic stroke, systemic embolism and device- or procedure-related adverse events that require open heart surgery or a major endovascular intervention prior to hospital discharge—was seen in 0.45% of patients.
After 45 days, adverse rates remained “generally low.” The death rate was 0.81%, for example, while ischemic stroke was seen in 0.23% of patients and device-related blood clots were seen 0.44% of patients who underwent follow-up echocardiography or CT imaging. Effective device closure was seen in nearly all patients (99.6%) after 45 days.
Finally, one-year outcomes included an all-cause death rate of 8.2%, stroke rate of 1.5%, ischemic stroke rate of 1.2% and major bleeding rate of 6.4%.
“In this large, contemporary cohort of patients with the Watchman FLX device from the LAAO registry, patients had higher thromboembolic and bleeding risk compared with patients enrolled in the PINNACLE FLX trial,” the authors wrote. “However, the implantation and procedural complication rates were similar to the trial, highlighting that appropriate patients are being treated with proper expertise after the commercialization of the procedure.”
Kapadia et al. also explored key patient factors that may influence the likelihood of poor outcomes.
Men and older patients were associated with an increased risk of the study’s primary safety endpoint. The same was also true for patients who presented with a history of prior ablation, congestive heart failure, abnormal renal function or prior thromboembolic or clinically relevant bleeding events. Patients with a history of stroke, cardiomyopathy or chronic lung disease all faced a heightened stroke risk after one year.
Also, patients with diabetes, chronic lung disease, congestive heart failure, abnormal renal or liver function or prior bleeding events were all more likely to experience a bleeding event within the first year after treatment.
Boston Scientific, the company behind the Watchman FLX device, did fund this analysis. In addition, two co-authors—not the study’s lead author, however—were Boston Scientific employees.
Click here to read the complete analysis in Circulation: Cardiovascular Interventions, an American Heart Association journal.
Michael has more than 16 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.