Catecholaminergic polymorphic ventricular tachycardia, or CPVT, is a rare, but treatable, condition. It’s less common than LQTS, but does affect apparently healthy infants, children, adolescents, and adults.
With increased awareness, genetic testing, and effective treatment options, CPVT can be diagnosed early and sudden deaths can be prevented.
CPVT is caused by abnormalities in the way the heart muscle cells handle calcium. This results in heart rhythm problems that can cause fainting or sudden death. Events usually occur with exercise or during stress.
You can suspect a CPVT diagnosis when there is a family history of unexplained syncope (fainting), unexplained seizures, or sudden death in young people, especially in the setting of stress or exercise.
Syncope usually occurs during exercise or other activities that are associated with high adrenaline levels. You may faint or feel lightheaded. You may have an unpleasant awareness of your heartbeat. It may also happen when you feel emotionally stressed.
Your doctor will diagnose CPVT either through:
- treadmill stress testing to provoke heart rhythm abnormalities
- Holter monitoring, and/or implantable loop recorders
- sometimes a catecholamine infusion test is required
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 usually normal.
A resting ECG is usually normal in those with CPVT, and is therefore insufficient as a diagnostic tool.
CPVT runs in families – about a third of patients have a positive family history. Genetic testing is a very important diagnostic test of a patient suspected to have CPVT. Mutations in just one gene, RYR2, explain nearly two-thirds of all cases of CPVT
If you’re symptomatic, you should receive treatment. All children and young adults should be treated, even if they don’t have symptoms, because sudden death may be the first symptom.
The usual treatment involves taking beta-blocker medications daily. The dose of beta-blocker needs to be monitored closely, and exercise testing may help determine if the medication is effective. If you continue to have symptoms despite appropriate doses of beta-blockers, you may also require additional medications or devices.
Once a family member is identified with CPVT, it is extremely important that other family members be tested for the syndrome. This screening, by treadmill testing or Holter monitoring, will allow all affected family members to be identified and treated early in order to prevent tragic and unnecessary sudden deaths.