Catecholaminergic polymorphic ventricular tachycardia or CPVT is a condition that results in ventricular rhythm problems (bidirectional and polymorphic ventricular tachycardia and ventricular fibrillation) that can cause fainting or sudden death. Events usually occur with exercise or during stress. CPVT is caused by abnormalities in the way the heart muscle cells handle calcium.
Fainting – caused by ventricular tachycardia - usually with exercise or other activities that are associated with high adrenaline levels.
Cardiac arrest if the ventricular tachycardia degenerates into ventricular fibrillation. Cardiac arrest may be the first symptom in CPVT patients.
CPVT is diagnosed primarily by
either treadmill stress testing to provoke rhythm abnormalities, or
catecholamine provocation testing
In children too young to perform exercise testing a 24-hour Holter monitor may help with the diagnosis. (In children with CPVT, the heart muscle function and the heart structure are normal). Note: a resting ECG that is usually normal