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aVR sign as a risk factor for life-threatening arrhythmic events in patients with Brugada syndrome
Mohamad Ali Babai Bigi1, Amir Aslani, Shahab Shahrzad
1Cardiology Department, Shiraz University of Medical Sciences, Shiraz, Iran.
Background:
Risk stratification in Brugada syndrome (BS) is controversial, especially in asymptomatic individuals.
Objective:
The aim of this study was to evaluate the significance of lead aVR in patients with BS.
Methods:
Twenty-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.
Results:
Thirteen 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.
Conclusion:
Our 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.
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