BACKGROUND: PINNACLE FLX (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the WATCHMAN FLX LAA Closure Technology) demonstrated improved outcomes and low incidence of adverse events with the WATCHMAN FLX device in a controlled setting. The National Cardiovascular Disease Registry's Left Atrial Appendage Occlusion Registry was utilized to assess the safety and effectiveness of WATCHMAN FLX in contemporary clinical practice in the United States.
METHODS: The WATCHMAN FLX Device Surveillance Post Approval Analysis Plan used data from the Left Atrial Appendage Occlusion registry to identify patients undergoing WATCHMAN FLX implantation between August 2020 and September 2022. The key safety end point was defined as all-cause death, ischemic stroke, systemic embolism, or device or procedure-related events requiring open cardiac surgery or major endovascular intervention between device implantation and hospital discharge. Major adverse events were reported at hospital discharge, 45 days, and 1 year.
RESULTS: Among 97 185 patients in the Left Atrial Appendage Occlusion registry undergoing WATCHMAN FLX, successful implantation occurred in 97.5% (n=94 784) of patients. The key safety end point occurred in 0.45% of patients. At 45 days post-procedure, all-cause death occurred in 0.81% patients, ischemic stroke in 0.23%, major bleeding in 3.1%, pericardial effusion requiring intervention in 0.50%, device-related thrombus in 0.44%, and device embolism in 0.04% patients. No peri-device leak was observed in 83.1% of patients at 45 days. At 1 year, the rate of all-cause death was 8.2%, the rate of any stroke was 1.5% (ischemic stroke, 1.2%), and major bleeding occurred in 6.4% of patients.
CONCLUSIONS: In a large contemporary cohort of patients with the WATCHMAN FLX device, the rates of implant success and clinical outcomes through 1 year were comparable with the PINNACLE FLX study, demonstrating that favorable outcomes achieved in the pivotal approval study can be replicated in routine clinical practice.