Atrioventricular nodal reentry tachycardia (AVNRT) is a type of irregular heartbeat, also called an arrhythmia. It is the most common type of supraventricular tachycardia.

People with AVNRT have an irregularly fast heartbeat that often starts and ends suddenly. In AVNRT, the heart beats more than 100 times a minute. The condition is due to a change in heart signaling. There is an extra pathway for heart signals to travel, called a reentrant circuit. That extra pathway causes the heart to beat too early.

AVNRT tends to occur more often in young women. But anyone can have it at any age. AVNRT may not need treatment. When recommended, treatment may include specific actions or movements, medicines, or a heart procedure.