Left atrial appendage occlusion with the AMPLATZER Amulet device: one-year follow-up from the prospective global Amulet observational registry

Abstract

Aims: Left atrial appendage occlusion (LAAO) is a stroke prevention therapy for patients with non-valvular atrial fibrillation (AF). This study reports one-year outcomes from patients enrolled in the prospective global Amulet registry.

Methods and results: A total of 1,088 patients were recruited, aged 75±9 years; 65% of patients were male. The CHA2DS2-VASc and HAS-BLED scores were 4.2±1.6 and 3.3±1.1, respectively. Eighty-three percent (83%) of patients had contraindications to anticoagulation (OAC); 72% had a history of major bleeding. An AMPLATZER Amulet LAA occluder was successfully implanted in 99% of cases. Transoesophageal echocardiography one to three months after implant showed no residual flow or flow <3 mm in 98.4%. The observed ischaemic stroke rate was 2.9%/year. Device-related thrombus was noted in 1.7% of patients. There were ten cases between 0 and 90 days and eight cases between 91 and 365 days. Patients discharged without OAC (>80%), in particular those on single aspirin therapy, did not appear to have a higher risk of device-related thrombus. In the first year, major bleeding occurred at an annualised rate of 10.3%. All-cause mortality was 8.4% at one year.

Conclusions: In the global prospective Amulet registry of patients at high risk of stroke and bleeding, the annualised ischaemic stroke rate was 2.9%. The LAA was sealed in 98.4% after one to three months and device-related thrombus was observed in 1.7% of cases with only a minority of all patients on anticoagulation treatment.