Catecholaminergic polymorphic ventricular tachycardia in a patient with recurrent exertional syncope

Area of Science:

• Cardiology
• Genetics
• Electrophysiology

Background:

• Recurrent syncope and cardiac arrest in adolescents can indicate serious underlying cardiac conditions.
• Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare, life-threatening inherited arrhythmia triggered by adrenergic stress.

Purpose of the Study:

• To investigate the genetic basis and clinical presentation of CPVT in a young male patient.
• To highlight the diagnostic challenges and management strategies for CPVT.

Main Methods:

• Case report of a 16-year-old male presenting with syncope and cardiac arrest.
• Electrocardiogram (ECG) and echocardiography for cardiac assessment.
• Exercise and epinephrine stress testing to provoke arrhythmias.
• Genetic testing for mutations in the cardiac ryanodine receptor (RYR2).

Main Results:

• The patient exhibited bidirectional ventricular tachycardia and survived cardiac arrest.
• Diagnosis of CPVT was made, but stress tests only induced premature ventricular complex bigeminy.
• Genetic analysis revealed compound heterozygous missense mutations in the RYR2 gene, inherited from both parents.
• The proband was symptomatic with both mutations.

Conclusions:

• Compound heterozygous RYR2 mutations can cause symptomatic CPVT.
• Genetic testing is crucial for diagnosing CPVT, especially in cases with atypical stress test findings.
• Management involves avoiding strenuous physical activity and beta-blocker therapy.