Prevalence of J-Point Elevation in Sudden Arrhythmic Death Syndrome Families

ObjectivesThe purpose of this study was to assess the prevalence of J-point elevation among the relatives of sudden arrhythmic death syndrome (SADS) probands.BackgroundJ-point elevation is now known to be associated with idiopathic ventricular fibrillation. We hypothesized that this early repolarization phenomenon is an inherited trait responsible for a proportion of otherwise unexplained SADS cases.MethodsFamilies of SADS probands were evaluated in an inherited arrhythmia clinic. Twelve-lead electrocardiograms were analyzed for J-point elevation defined as >0.1 mV from baseline present in 2 or more of the inferior (II, III, and aVF) or lateral (1, aVL, V4 to V6) leads. Electrocardiographic data were compared with those of 359 controls of a similar age, sex, and ethnic distribution.ResultsA total of 363 first-degree relatives from 144 families were evaluated. J-point elevation in the inferolateral leads was present in 23% of relatives and 11% of control subjects (odds ratio: 2.54, 95% confidence interval: 1.66 to 3.90; p < 0.001).ConclusionsJ-point elevation is more prevalent in the relatives of SADS probands than in controls. This indicates that early repolarization is an important potentially inheritable pro-arrhythmic trait or marker of pro-arrhythmia in SADS.