Atrioventricular Nodal Reentry Tachycardia (AVNRT)

Diagnosis

Atrioventricular nodal reentry tachycardia (AVNRT) is diagnosed by a healthcare professional through a physical exam, reviewing your medical history, and listening to your heart and lungs with a stethoscope.

Tests to Diagnose AVNRT

Blood tests
Used to check for thyroid disease or other conditions that may trigger an irregular heartbeat.

Electrocardiogram (ECG or EKG)
Records the electrical activity of the heart to show how fast or slow it is beating.

Holter monitor
A portable ECG device worn for a day or more to record heart activity during daily life. It can detect fast or irregular heartbeats not captured on a standard ECG.

Echocardiogram
Uses sound waves to create images of the beating heart, showing heart size and blood flow.

Exercise stress tests
Monitor heart activity while walking on a treadmill or riding a stationary bike. If you cannot exercise, medicine may be used to simulate the effects of exercise on the heart.

Electrophysiological (EP) study
A specialized test that pinpoints where the irregular heartbeat originates. Flexible tubes called catheters are guided through a blood vessel to the heart. Sensors at the tips record the heart’s electrical signals.

Treatment

Many people with AVNRT do not need treatment. However, if fast heartbeats are frequent or prolonged, treatment options may include:

Vagal maneuvers
Simple actions such as coughing, bearing down, massaging the neck artery, or applying an ice pack to the face can stimulate the vagus nerve to slow the heart rate.

Medicines
Prescribed to control heart rate or prevent frequent episodes of fast heartbeat.

Cardioversion
Electric shocks are delivered via paddles or patches on the chest to reset the heart rhythm, typically used when vagal maneuvers and medicines are ineffective.

Catheter ablation
Recommended if medicines are ineffective or cause side effects. A thin, flexible catheter is inserted into a blood vessel and guided to the heart. Heat or cold energy creates tiny scars that block abnormal electrical signals, restoring a normal heartbeat.