aVR sign as a risk factor for life-threatening arrhythmic events in patients with Brugada syndrome

BackgroundRisk stratification in Brugada syndrome (BS) is controversial, especially in asymptomatic individuals.ObjectiveThe aim of this study was to evaluate the significance of lead aVR in patients with BS.MethodsTwenty-four patients with the electrocardiogram pattern of BS (24 male, mean age 32.1 ± 13.6 years) and 24 healthy age- and gender-matched controls were studied.ResultsThirteen patients were symptomatic. The R-wave amplitude or R/q ratio in lead aVR was significantly greater in patients experiencing a recurrence compared with those who did not. The aVR sign was defined as R wave ≥ 0.3 mV or R/q ≥ 0.75 in lead aVR. Most of the recurrences (78%) were in patients with present aVR sign; 84% of BS patients with present aVR sign had events during follow-up. In contrast, only 27% of BS patients with absent aVR sign had events during follow-up.ConclusionOur study shows significant correlation between a prominent R wave in lead aVR (aVR sign) and risk for development of arrhythmic events in BS. In the presence of BS, prominent R wave in lead aVR may reflect more right ventricular conduction delay and subsequently more electrical heterogeneity, which in turn is responsible for a higher risk of arrhythmia.