If an abnormal focus is found it can be treated through the same catheter. This type of testing and treatment is becoming common as more centers develop the expertise. Finally, there are ventricular tachycardias, caused by an abnormal focus in the ventricles which stimulate the tachycardia. Ventricular tachycardia is often associated with structural heart disease. SVTs may be very frightening, with a rapid pounding heartbeat.
People commonly believe that they are dying.
However, an SVT arising in someone with a healthy heart is rarely life threatening, and the heart can go on beating rapidly literally for hours. Therefore, it is seldom a cause of sudden death, and a person having such an attack usually has plenty of time to get to an emergency room for treatment. Ventricular tachycardias on the other hand are much more dangerous. They seldom occur in a healthy heart, and the tachycardia therefore will compound any other heart problem already present. They also can degenerate into ventricular fibrillation, which is a common cause of sudden death in people who have had a heart attack.