Gary Tse1, Sharen Lee2, Ngai Shing Mok3, Tong Liu4, Dong Chang5. 1. Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, PR China; Xiamen Cardiovascular Hospital, Xiamen University, Xiamen, PR China. 2. Laboratory of Cardiovascular Physiology, Li Ka Shing Institute of Health Sciences, Hong Kong, China. 3. Department of Medicine and Geriatrics, Princess Margaret Hospital, Hong Kong, China. 4. Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, PR China. Electronic address: liutongdoc@126.com. 5. Xiamen Cardiovascular Hospital, Xiamen University, Xiamen, PR China. Electronic address: cdheart@126.com.
Abstract
BACKGROUND: Atrial electrophysiological abnormalities have previously been reported in Brugada syndrome. We investigated the incidence and electrocardiographic predictors of atrial fibrillation (AF) in a Chinese cohort of Brugada syndrome patients. METHODS: A retrospective study of Brugada syndrome patients admitted to tertiary centers in Hong Kong. RESULTS: A total of 275 patients were included (median age at presentation: 53 [40-64], 247 (90%) males) with a median follow-up duration of 67 (31-113) months. A total of 14 patients (5%) developed AF. Inter-atrial block and AV block were found in 36% (n = 100) and 13% (n = 37) of all patients. Compared to those in sinus rhythm, patients with AF showed significantly longer P-wave duration (PWD) (125 [116-137] vs. 114 [106-124] ms, P = 0.009) and PR interval (190 [163-214] vs. 169 [153-184] ms; P = 0.023). They were more likely to develop syncope (79 vs. 43%; P = 0.012) or VT/VF (43 vs. 14%; P = 0.012), undergo electrophysiological studies (36 vs. 19%; P = 0.005) and receive ICDs (71 vs. 25%; P = 0.001). Univariate logistic regression showed that mean PWD (odds ratio [OR]: 1.03 [1.00-1.06], P = 0.021), PR interval (OR: 1.02 [1.01-1.04]; P = 0.010) and QT interval (OR: 1.02 [1.00-1.04], P = 0.012), syncope (OR: 4.80 [1.31-17.61], P = 0.018) and R-wave amplitude in lead V5 (OR: 0.30 [0.09-1.00]; P = 0.05) significantly predicted incident AF. Receiver operating characteristic analysis revealed an optimum cut-off point of 123 ms and area under the curve of 0.71 for PWD. CONCLUSION: The incidence of AF was 5% in this cohort. PWD, PR and QT intervals significantly predicted AF and are simple electrocardiographic markers for identifying potential at-risk patients.
BACKGROUND: Atrial electrophysiological abnormalities have previously been reported in Brugada syndrome. We investigated the incidence and electrocardiographic predictors of atrial fibrillation (AF) in a Chinese cohort of Brugada syndromepatients. METHODS: A retrospective study of Brugada syndromepatients admitted to tertiary centers in Hong Kong. RESULTS: A total of 275 patients were included (median age at presentation: 53 [40-64], 247 (90%) males) with a median follow-up duration of 67 (31-113) months. A total of 14 patients (5%) developed AF. Inter-atrial block and AV block were found in 36% (n = 100) and 13% (n = 37) of all patients. Compared to those in sinus rhythm, patients with AF showed significantly longer P-wave duration (PWD) (125 [116-137] vs. 114 [106-124] ms, P = 0.009) and PR interval (190 [163-214] vs. 169 [153-184] ms; P = 0.023). They were more likely to develop syncope (79 vs. 43%; P = 0.012) or VT/VF (43 vs. 14%; P = 0.012), undergo electrophysiological studies (36 vs. 19%; P = 0.005) and receive ICDs (71 vs. 25%; P = 0.001). Univariate logistic regression showed that mean PWD (odds ratio [OR]: 1.03 [1.00-1.06], P = 0.021), PR interval (OR: 1.02 [1.01-1.04]; P = 0.010) and QT interval (OR: 1.02 [1.00-1.04], P = 0.012), syncope (OR: 4.80 [1.31-17.61], P = 0.018) and R-wave amplitude in lead V5 (OR: 0.30 [0.09-1.00]; P = 0.05) significantly predicted incident AF. Receiver operating characteristic analysis revealed an optimum cut-off point of 123 ms and area under the curve of 0.71 for PWD. CONCLUSION: The incidence of AF was 5% in this cohort. PWD, PR and QT intervals significantly predicted AF and are simple electrocardiographic markers for identifying potential at-risk patients.