FAMILIAL INCIDENCE OF LATE VENTRICULAR POTENTIALS AND ELECTROCARDIOGRAPHIC ABNORMALITIES IN ARRHYTHMOGENIC RIGHT-VENTRICULAR DYSPLASIA

Familial forms of arrhythmogenic right ventricular dysplasia (ARVD) ha ve been described. Signal-averaged electrocardiograms (SAECGs) and sta ndard electrocardiograms have been used to detect ARVD. The purpose of this prospective study, for a given family member, was to evaluate th e risk of having ARVD or only belonging to an affected family. To addr ess these issues, we assessed the incidence of late ventricular potent ials and electrocardiographic (ECG) abnormalities in the families of o ur patients with ARVD. SAECGs and electrocardiograms were recorded in 101 eligible family members and compared with those recorded in ARVD p atients with sustained ventricular tachycardia (13 patients in 12 fami lies), and in 37 control subjects with a normal electrocardiogram. The incidence of late ventricular potentials was significantly higher in family members than in control subjects (16% vs 3%, p <0.05). The inci dence of ECG abnormalities was 34% in family members. When the inciden ce of late ventricular potentials and/or ECG abnormalities were added up, results were 38% abnormal findings in family members. Late ventric ular potentials and/or ECG abnormalities were found in members of all 7 families; these abnormalities were initially thought to be sporadic forms, and thereafter were classified as familial forms. Thus, SAECGs and standard ECG recordings in ARVD family members showed 38% abnormal findings, and that all cases of ARVD could be classified as familial forms. The incidence of familial forms of ARVD was greater than was pr eviously believed, which is highly suggestive of a genetic transmissio n of the disease in our geographic area. (C) 1997 by Excerpta Medico, Inc.