Supaventricular tachycardia (SVT) is a rapid type of heartbeat of the upper heart chambers. During SVT, electrical signals travel from the upper heart chambers to the lower heart chambers from as little as 100 beats per minute to 300 beats per minute.
Types of SVT include:
- Atrioventricular nodal reentrant tachycardia (AVNRT) – Electrical signals travel around the AV node in a circular motion, as if going around a racetrack.
- Atrioventricular reciprocating tachycardia (AVRT) – Electrical signals go down one staircase from the top chamber to the bottom chamber and then takes the second staircase from the bottom chamber and back up to the upper chamber
SVT can be caused by bad electrical connections in the heart or by certain medications. The condition can also be genetic.
SVT usually has no symptoms and can start and end quickly. Similar to AF and AFL, symptoms can include:
- Heart palpitations
- Fast pulse
- Chest pain
- Lightheadedness and fainting
The most common type of treatment includes medicine like beta-blockers and calcium channel blockers. More serious symptoms of SVT can also be treated with an ablation procedure, a catheter-based procedure that delivers electrical signals to the heart tissue to stop abnormal firings of the heart.