Your heart beats about 100,000 times a day. Sometimes it beats faster and sometimes more slowly, depending on what you're doing and whether, for instance, you're all worked up about something. So ...

A racing heart is usually a sign of agitation or excitement. But if it's not unusual for your heart to beat too fast or to skip a beat, it might be worth having it checked out by a doctor. In order to ...

In atrial fibrillation, the heartbeat is very irregular and often fast. Doctors use medicines to control both the speed and ...