Fast Heartbeat May Raise Stroke Risk

People with a very fast heartbeat that is not causing symptoms may still have a higher risk of stroke, new research finds. The study included 2,580 older adults with high blood pressure. All of them had a pacemaker or defibrillator implanted to help control their heart rhythm. This device kept a record of the speed and rhythm of their heart over time. None of the people had a known history of atrial fibrillation. This is a very fast, irregular rhythm in the heart’s upper chambers. It causes them to quiver rather than beat normally. Soon after the study started, the devices recorded a very rapid heartbeat that lasted several minutes in about 1 out of 10 people. They usually had no symptoms. But in the next 2 ½ years they were more likely to develop lasting atrial fibrillation. They also were more likely to have a stroke.