Supraventricular Tachycardia (SVT)

Supraventricular tachycardia (SVT) is an abnormally fast heart rhythm arising from improper electrical activity in upper part of the heart. There are four main types: atrial fibrillation, paroxysmal supraventricular tachycardia (PSVT), atrial flutter, and Wolff-Parkinson-White syndrome. Symptoms may include palpitations, feeling faint, sweating, shortness of breath, or chest pain.

They start from either the atria or atrioventricular node. They are generally due to one of two mechanisms: re-entry or increased automaticity. The other type of fast heart rhythm are ventricular arrhythmias—rapid rhythms that start within the ventricle. Diagnosis is typically by electrocardiogram (ECG), holter monitor, or event monitor. Blood tests may be done to rule out specific underlying causes such as hyperthyroidism or electrolyte abnormalities.

Specific treatments depend on the type of SVT. They can include medications, medical procedures, or surgery. Vagal maneuvers or a procedure known as catheter ablation may be effective in certain types.