PLAATO Data Support ev3's Occlusion Device at 5 Years

July 2, 2009—In the Journal of the American College of Cardiology: Cardiovascular Interventions, Peter C. Block, MD, et al published 5-year results of the PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) study, which aimed to determine 5-year clinical status for patients treated for percutaneous left atrial appendage transcatheter occlusion with the PLAATO system (ev3, Inc., Plymouth, MN) (2009;2:594–600). The investigators concluded that the device is safe and effective with a 5-year follow-up stroke/transient ischemic attack rate of 3.8% per year, which was less than that predicted by the CHADS2 scoring system.

According to the investigators, anticoagulation reduces thromboembolism among patients with nonvalvular atrial fibrillation (AF). However, warfarin is a challenging medication due to risks of inadequate anticoagulation and bleeding. Thus, PLAATO was evaluated as a treatment strategy for nonwarfarin candidate patients with AF who were at a high risk for stroke. Sixty-four patients with permanent or paroxysmal AF participated in this observational, multicenter, prospective study. Primary endpoints were new major or minor stroke, cardiac or neurological death, myocardial infarction, or requirement for cardiovascular surgery related to the procedure within 1 month of the index procedure. Patients were followed for up to 5 years.

The investigators reported that the 30-day freedom from major adverse events rate was 98.4% (95% confidence interval, 90.89% to > 99.99%). One patient, who did not receive a PLAATO implant, experienced two events within 30 days (cardiovascular surgery and death). Treatment success was 100% at 1 month after device implantation. At 5-year follow-up, there were seven deaths, five major strokes, three minor strokes, one cardiac tamponade requiring surgery, one probable cerebral hemorrhage/death, and one myocardial infarction. One event (cardiac tamponade) was adjudicated as related to the implant procedure. After up to 5 years of follow-up, the annualized stroke/transient ischemic attack rate was 3.8%, which was less than predicted by the anticipated rate of 6.6% with the CHADS2 scoring method.