Atrioventricular nodal reentry tachycardia (AVNRT)

Diagnosis

AVNRT can be diagnosed by the following:

• Blood tests: for thyroid disease, cardiac disorders and other health concerns that raise the risk of developing irregular heartbeats.
• Electrocardiogram (ECG):used to look at the functioning of cardiac electrical signals including the timing and duration of the heartbeat.
• Holter monitor: helps the doctor record the activities of the heart with this portable ECG device while you are doing your normal activities.
• Echocardiogram: which creates images of your heart and shows its size, structure and movement with sound waves.

AVNRT can also be diagnosed by deliberately triggering an episode of the disease. The following tests are used to trigger the symptoms:

• Stress test: A patient is required to run on a treadmill or stationary bicycle while having the cardiac activity recorded and analyzed.
• Electrophysiological study and cardiac mapping: help the doctor with the location of the arrhythmia occurrence.

Treatment

Most people with AVNRT don’t need treatment. Those with frequent or prolonged episodes of AVNRT or those that have symptoms continuously recurring might be recommended any of the following treatment approaches:

• Vagal maneuvers: a process that requires you to hold your breath and strain, dunk your face in ice water, or cough to stop the episode of AVNRT.
• Cardioversion: This option is recommended for patients who do not respond well to vagal maneuvers. In this process, you will either be prescribed medications or receive a shock to the heart sent from paddles or patches on your chest. Your doctor uses the shocking process to restore a normal heart rhythm.
• Medications: which are mostly prescribed to those with frequent episodes of AVNRT to put the heart rate under control or make the heart rhythm normal.
• Catheter ablation: One or more catheters are delivered into the blood vessels before being guided to the heart. The surgeons will then use sensors at the tip of the catheter to create scars on the heart’s lining to block the irregular signals that are causing the heart to beat faster. In order to close the scars radiofrequency which is heat energy or extreme cold energy called cryoablation is used.