The future is unclear for a promising heart device aimed at preventing strokes in people at high risk of them because of an irregular heartbeat.
Early results from a key study of Boston Scientific Corp.'s Watchman device suggest it is safer than previous testing suggested, but may not be as good as a drug that is used now for preventing strokes, heart-related deaths and blood clots in people with atrial fibrillation. That condition causes the heart to flutter rather than beat as it should, which can lead to clots that cause strokes.
The results were to have been the top study at an American College of Cardiology conference in San Francisco on Saturday but the presentation was pulled because the company released results early.
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