Left atrial appendage closure with the Watchman device yielded low rates of death, intracranial hemorrhage, stroke and transient ischemic attack at long-term follow-up out to 5 years, according to new data.
Researchers conducted a prospective, single-center study of 102 consecutive patients (mean age, 71.6 ± 8.8 years; 37.3% women) with nonvalvular AF who were implanted with the second-generation Watchman left atrial appendage (LAA) closure device (Boston Scientific) between June 2006 and August 2010. Eligible patients had CHADS2 or CHA2DS2-VASc scores of at least 1, ejection fraction of at least 30%, and no severe mitral insufficiency, mitral stenosis or thrombus formation in the left atrium or the LAA. Patients were seen for follow-up between 45 days and 3 months after implantation, and transesophageal electrocardiography (TEE) was used to assess peri-device flow, device stability and positioning. Patients also were assessed by TEE and electrocardiography at 6-month and 1-year follow-up. After 1 year, participants were followed annually and then every 6 months by alternating office visits or telephone interviews.
The mean patient follow-up was 3 ± 1.6 years, with a maximum of 5 years. The mean CHADS2 score was 2.7 ± 1.3 and the mean CHA2DS2-VASc score was 4.3 ± 1.7.
The device was successfully implanted in 96% (98 of 102) of patients, and post-implantation TEE and fluoroscopic imaging revealed successful closure of the LAA in 97 of 98 patients.
During follow-up, thrombus formation occurred in one patient 3 months after the procedure, and in a second patient 6 months after the procedure. Two patients experienced ischemic strokes more than 12 months after implantation, and two additional patients experienced TIA. Three patients showed evidence of intracranial bleeding. In one patient, evidence of bleeding was seen while on vitamin K agonists; in a second patient, the bleeding occurred while on aspirin and clopidogrel; and in the third patient, intracranial bleeding occurred while on aspirin therapy alone. The third patient died at 26 months after implantation. The following annual event rates were documented during follow-up: TIA, 0.7%; stroke, 0.7%; intracranial hemorrhage, 1.1%; and death, 3.5%.
“Our findings suggest that low procedural complications rates with the Watchman device may result in a more pronounced benefit of percutaneous LAA occlusion than previously expected,” the researchers wrote. “Long-term data from our study confirm the safety and efficacy of LAA occlusion with the Watchman device for stroke protection, irrespective of the postprocedural anticoagulant regime. Thus, LAA occlusion represents a reasonable alternative to oral anticoagulation.” – by Jennifer Byrne
Disclosure: One researcher reports receiving study honoraria, travel expenses and consultant fees from Boston Scientific and other companies.