Arrhythmia is an abnormal heart rhythm created by a disturbance in the heart's electrical system. During an arrhythmia, the heart may beat too fast, too slow or in an irregular pattern. Certain abnormal heart rhythms can be very dangerous, and in some cases even fatal. On the other hand, some arrhythmias are common, so-called benign arrhythmias, and aren't associated with health problems.
Years ago, the only treatments for abnormally fast heart rhythms, known as tachycardias, was medication or, in extreme cases, open heart surgery. Today, radiofrequency catheter ablation — a procedure pioneered by UCSF cardiologists — destroys the abnormal electrical pathway that causes the condition. The procedure delivers a pinpoint of heat inside the heart. Another procedure, called cryoablation, destroys the abnormal cells or electrical pathway by freezing.
A premature heartbeat comes too soon and interrupts the regular rhythm of the heart. Premature beats may originate in the atrium, called a premature atrial contraction or PAC, or in the ventricles, called a premature ventricular contraction or PVC. These premature heartbeats can make it feel like your heart is skipping or flip-flopping.
Although premature beats are more common in people with heart disease, almost everyone has experienced a skipped beat once in a while, which may be due to smoking, fatigue, alcohol, caffeine and other stimulants, or may have no apparent cause. Usually single premature beats require no treatment. However, when they are frequent or annoying, your doctor may recommend a test to search for their cause.