Cardiac electrophysiology, or simply electrophysiology, is a subspecialty of cardiology. Cardiac electrophysiologists are doctors who really feel the beat: they specialize in the rhythm of the heart and the way it uses electrical impulses to move.
Cardiac electrophysiologists diagnose problems with heartbeats, or arrhythmias. Arrhythmias can be present at birth or simply come with age. Other medical conditions can also affect the heart's rhythm: for example, sleep disorders, diabetes, high blood pressure, and hardened arteries.
Cardiac electrophysiologists treat heart rhythm disorders with medication or surgical procedures. One such procedure is called an "ablation," which uses radio frequency waves to kill heart cells that may be misfiring. Cardiac electrophysiologists can also implant devices that control the rhythm of the heart, such as pacemakers or defibrillators.