PSVT, or Paroxysmal Supraventricular Tachycardia (PSVT), is an arrhythmia or unusual heart rhythm triggered by short circuits in the upper heart chambers. During PSVT, your heart beat will be regular but fast, occurring in short bursts that start and stop abruptly.
Every heartbeat starts when an electrical signal is initiated from the Sinoatrial Node or SA Node in the right atrium. These electrical impulses are generated at 60-100 per minute. In Supraventricular tachycardia, most commonly referred to as SVT, the electrical stimulation is generated elsewhere in the upper chambers suddenly at a very fast rate (usually 150-250 beats/min).
The leading reason for PSVT is Atrioventricular Nodal Reentrant Tachycardia (AVNRT). An electrical impulse entering the small extra path close to the Atrioventricular node will circulate rapidly, resulting in a paroxysmal or sudden rapid heartbeat in both ventricles and the atria.
Lightheadedness or syncope, or fainting spells are common symptoms of AVNRT, although it is not a fatal arrhythmia.