Arrhythmogenic right ventricular cardiomyopathy (ARVC) formerly referred to as arrhythmogenic right ventricular dysplasia (ARVD) is a familial hetergenous clinical and molecular disease characterized by dilatation and dysfunction of the right ventricle and ventricular arrhythmias. The ventricular arrhythmias are heart rate and catecholamine dependent. Not infrequently, there is involvement of the left ventricle. The diagnosis of ARVC is critical as therapy including implantable defibrillators may prevent sudden death. However, identification of affected family members remains a major challenge due to limitation of current imaging and diagnostic techniques. We propose (1) to establish the sensitivity and specificity of the isoproterenol challenge test for ARVC by testing both patients with known ARVC and healthy volunteers; (2) to estimate the proportion of family members who present with incomplete criteria for ARVC but are subsequently diagnosed with the condition by an isoproterenol challenge test; and, (3) to study the inheritance of ARVC and the potential role of occult infection in its development.
INCLUSION CRITERIA: Patients with ARVC: Either gender, aged greater than 5 years. The presence of two major criteria; one major and two minor criteria; or four minor criteria from separate diagnostic categories. Normal Volunteers: Age and gender matched with ARVC patients, age greater than 18 years. No known cardiac disease. Normal EKG, normal echocardiogram, normal Bruce protocol treadmill exercise test. Family Members of Patients with ARVC: Either gender, aged greater than 5 years. A proband with ARVC EXCLUSION CRITERIA: Patients with ARVC: Pregnancy or lactation excludes tests with potential risk, e.g. radiation, isoprenaline, MRI, but does not exclude 12-lead ECG and echocardiogram. Coronary artery disease. Known infiltrate or congenital heart disease that could mimic the appearances of ARVC. Asthma prevents participation in Isoproterenol infusion. Any other condition that would prevent participation in the study. Normal Volunteers: Pregnancy or lactation. Asthma. Coronary artery disease, hypertension, diabetes, hypertrophic cardiomyopathy, or other known cardiomyopathy. Known infiltrative or congenital heart disease that could mimic the appearances of ARVC. Any Acute or chronic illness. Chronic drug therapy. Family Members of Patients with ARVC: Pregnancy or lactation excludes tests with potential risk, e.g. radiation, isoprenaline, MRI, but does not exclude 12-lead ECG and echocardiogram. Coronary artery disease. Known infiltrative or congenital heart disease that could mimic the appearances of ARVC. Asthma prevents participation in Isoproterenol infusion. Any other condition that would prevent participation in the study.