Device closure of LAA and stroke prevention

The Embolic Protection in Patients with Atrial Fibrillation (PROTECT-AF) study was presented at the American College of Cardiology 2009 Scientific Sessions by Dr David R Holmes Jr, the Principal Investigator.

The study included 800 patients aged 18 years or more with documented non-valvular atrial fibrillation who were able to tolerate long-term warfarin. Exclusion criteria included NYHA class IV heart failure, symptomatic carotid disease and a left ventricular ejection fraction below 30%. Patients were randomised in a device-to-control ratio of 2:1, and were followed up clinically and by transoesophageal echocardiography. Device group patients were given warfarin up to day 45 (to allow endothelialisation) but warfarin was then discontinued.

Eighty-seven percent of patients fitted with the device were able to discontinue warfarin treatment.

There was a two-fold increase in safety events in the device group (8.7% versus 4.2%), pericardial effusions representing the largest fraction of safety events. Stroke events were the most serious events in the control group, and bleeding events were also frequent.

By contrast, patients who received the device had improved primary efficacy rates (3.4% versus 5.0%, relative risk [RR] 0.68). For all strokes, there was a 2.6% device event rate and a 3.5% control event rate (relative risk 0.74). Ischaemic strokes were more common in the device group (RR1.53) but haemorrhagic stroke was lower in the device group (0.2% versus 1.9%, RR 0.09, meeting superiority criteria).

In practice, this device may be used first in high-risk patients who cannot tolerate warfarin treatment. The device was scheduled to go before the FDA advisory panel in April.