• Cardiology Clinical Trials
• Interventional Techniques & Devices
• Arrhythmias

The first formal analysis of the ASA-Plavix (ASAP) Registry found that the Watchman left atrial appendage closure device can be used safely and effectively in patients with atrial fibrillation (AF) for whom anticoagulants are contraindicated. Vivek Y. Reddy, MD, Mount Sinai School of Medicine, New York, New York, USA, presented findings from the study.

The purpose of the prospective, nonrandomized, multicenter study was to determine if the Watchman device can be used safely without a warfarin transition in patients with AF and if the device decreases the subsequent risk for stroke. After receiving the device, all of the patients received 6 months of clopidogrel and indefinite aspirin.

The study included 150 patients with paroxysmal, persistent, or permanent nonvalvular AF; a CHADS₂ score of ≥1; and a contraindication for warfarin. Follow-up visits took place at 3, 6, 12, 18, and 24 months and included transesophageal echocardiogram imaging, neurological assessment, Barthel Index/Modified Rankin, and NIH stroke scale. Patients were monitored for a total of 14.4±8.6 months, with a compliance rate of 99.4%.

The mean age of patients was 72.5±7.4 years; 64% were male. Most patients had hypertension (94.7%); 67% had a history of overt bleeding; 61 (40.7%) had a prior stroke, transient ischemic attack, or systemic embolism. Participants were required to have a CHADS₂ score of at least 1, and the average was 2.8 (current guidelines recommend anticoagulation in those with a CHADS₂ score of 2 or above).

Overall implant success at the 4 study sites (3 in Germany and 1 in the Czech Republic) was 94.7%. The mean procedure time was 51.5±27.7 minutes. Measured as events per patient-year, the rate of death from any cause was 5.0% and for all stroke, 2.3%. The rate of major bleeding events, mostly gastrointestinal, was 2.7%. Five patients (3.3%) had device thrombus without sequelae.

According to Dr. Reddy, the expected rate of ischemic stroke, based on the distribution of CHADS₂ scores, was 7.3%; the observed rate in ASAP patients was 1.7%, a relative 77% lower than predicted. The expected rate, if clopidogrel was used throughout follow-up, was 5.1%; the observed rate was a relative 67% lower.

Dr. Reddy noted that a significant number of patients with AF who can not or will not take warfarin are at risk for stroke, and pharmacological alternatives are not suitable. He concluded that Watchman implantation without a warfarin transition is feasible, with a low but manageable rate of device thrombus.

• © 2012 MD Conference Express