St. Jude Medical (NYSE:STJ) announced on Friday that it has enrolled the first patient in its trial to judge the effectiveness of its Amplatzer Cardiac Plug in preventing stroke in patients suffering from atrial fibrillation. The trial, dubbed the ACP Trial, will measure both efficacy and safety of the device, while enrolling between 400 and 3,000 patients in the U.S. and Canada.

The American Heart Association estimates 2.7 million Americans suffer from atrial fibrillation, making the market a potentially lucrative one for St. Jude. The World Health Organization further projects around a third of all atrial fibrillation patients will suffer a stroke in their lifetimes if not treated.

The Amplatzer Cardiac Plug first  won CE Mark approval in 2008, and St. Jude is hoping successful data from the ACP Trial can contribute to an FDA approval, as well.

St. Jude's President of Medical Cardiovascular and Ablation Technologies Division, Frank J Callaghan, explained the opportunity provided by the trial, saying:

The AMPLATZER Cardiac Plug has shown great promise in international markets and we look forward to establishing the evidence required to make it available in the U.S.... This trial will help us understand the long-term benefits of LAA occlusion therapy for lowering the risk of stroke in atrial fibrillation patients and potentially improve their quality of life.

St. Jude shares rose 1.3% on Friday with the announcement.