Sign up for CNN’s Sleep, But Better newsletter series. Our seven-part guide has helpful hints to achieve better sleep. About 1 in 4 women may experience irregular ...

An arrhythmia, or irregular heartbeat, is a problem with the rate or rhythm of the heartbeat. People with this condition may have a heart that beats too quickly, too slowly or has an irregular rhythm.

Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable ...