ORLANDO, Fla. A device to treat a common heart problem that can lead to stroke shows promise, according to a new study.

The device, called the Watchman, targets a heartbeat problem called atrial fibrillation. The current standard treatment is the drug warfarin, but it requires frequent blood tests to get the dose right.

A study presented at a cardiology conference in Orlando, Fla., showed the Watchman was just as effective as the drug. However, the research showed there were safety risks with it, too. The Watchman is made by Atritech of Minnesota.