What is supraventricular tachycardia? Is it serious?

See below. Supraventricular tachycardia (svt) is an episodic fast heart rate that usually originates in the upper chambers of the heart. It usually starts all of a sudden and stops all of a sudden, usually is not life threatening by itself, and is mostly rather easily treatable with a cardiac procedure called ablation which is performed by an electrophysiologist.
Arrhythmia coming . From top chambers of the heart (atria)...Can be serious depending upon symptoms. See a cardiologist and get evaluated as many treatments are available.