catecholaminergic polymorphic ventricular tachycardia

(redirected from CPVT)
Also found in: Acronyms, Wikipedia.

catecholaminergic polymorphic ventricular tachycardia

An inherited cardiac conduction disorder of early onset (age 7 to 9), which is characterised by episodic syncope occurring during exercise or acute emotion, which triggers ventricular tachycardia, usually followed by spontaneous recovery or less commonly by ventricular fibrillation and sudden death without CPR.

Diagnosis
Reproducible ventricular arrhythmias during exercise stress testing.

EKG
Alternating 180-degree-QRS axis on a beat-to-beat basis, so-called bidirectional VT, and irregular polymorphic VT without a "stable" QRS vector alternans.

Management 
Beta-blockers, even in absence of clinical disease; implantable cardioverter-defibrillator for recurrent cardiac arrest, anticoagulation as needed.

Prevent secondary complications 
Avoid exacerbating asthma, cardiac-specific beta-blocker: metoprolol is preferred. Follow-up visits with a cardiologist every 6–12 months to monitor therapy.
Avoid competitive sport and strenuous exercise.
Test blood relatives at risk with resting EKG, Holter monitoring, and exercise stress testing.

Genetic counselling
(1) RYR2-related CPVT is autosomal dominant—i.e., each child has a 50% chance of inheriting the mutation.
(2) CASQ2-related CPVT is autosomal recessive—i.e., each parent of an affected child is a carrier.
Mentioned in ?
References in periodicals archive ?
The researchers developed a mouse model for CPVT (by eliminating the calsequestrin gene) and proposed using the model to study medications and interventions for the disorder.
In isolated heart cells, flecainide blocked the ryanodine receptor and the calcium "leak" (the underlying molecular defect in CPVT), and it completely prevented ventricular arrhythmias in the mouse model of CPVT.
Ackerman says that to identify at-risk relatives, all immediate family members of the person who died inexplicably must undergo comprehensive cardiac evaluation that includes, at a minimum, an electrocardiogram and an exercise stress test as initial screens for LQTS and CPVT.