Atrioventricular Nodal Reentrant Tachycardia (AVNRT)

What is AVNRT

Atrioventricular nodal reentrant tachycardia (AVNRT) is a type of abnormal heart beat. It is the most common type of supraventricular tachycardia (SVT), accounting for about 60% of all SVTs.
AVNRT is known as a reentrant tachycardia. As with all reentrant SVT, patients with AVNRT have been born with an extra electrical connection in the heart. In AVNRT, the extra connection - and the entire reentrant circuit that produces the arrhythmia - is located within the tiny atrioventricular node (AV node).

Symptoms of AVNRT

The symptoms of AVNRT are typical for SVT, and generally include a sudden onset of palpitations, lightheadedness, and/or dizziness. Episodes commonly last from a few minutes to several hours.

What are the risks of AVNRT

AVNRT is usually well tolerated, often occurring in patients with no structural heart disease.

Using antiarrhythmic drugs to prevent recurrent AVNRT is often only moderately effective. However, AVNRT can usually (more than 95% of the time) be cured with ablation therapy, in which the abnormal electrical connection within the AV node is carefully mapped and ablated.