The relationship between myocardial bridges and myocardial repolarization

Background: Although the muscular bridge (MB) which seen in the coronary arteries is known to be a benign condition, it is reported to be associated with adverse cardiac events in some studies. Although some condition such as coronary ischemia have been blamed in the occurrence of these adverse events, it is thought that the negative effects of myocardial electrical conduction will contribute to this situation.In this study, the relationship between electrocardiography parameters that demonstrate the electrical activity of the heart and the muscular bridgewas investigated. Material and Methods: This study included 36 patients (26 males, mean age 56 years) who were diagnosed with MB and 36 patients with normal coronary artery (30 male, mean age 51 years). 12- lead electrocardiography (ECG) was performed in supine position and QT interval, QT corrected (QTc), Tp-Te interval, Tp-Te/QT and Tp-Te/QTc measurements were performed. These parameters were compared between groups. Results: There were no significant differences between MB group and control group in terms of clinical and baseline demographic characteristics However, QT interval, QTc, Tp-Te interval, Tp-Te / QT and Tp-Te / QTc were significantly higher in the MB group. (360 ± 1.9 vs 355±2.3, p <0.001; 428.1 ± 1.6 vs 417.3±1.4, p <0.001; 83.3 ± 1.4 vs 72.1±1.3, p <0.001; 0.24 ± 0.005 vs 0.2±0.004, p <0.001; 0.2±0.003 vs 0.17±0.003, p <0.001). Multivariate analysis was performed to determine the independent predictors of the Tp-e interval. The length of MB was detected as an independent predictor of Tp-Te interval. (β = 0.530, p = 0.005) Conclusion: Length of MB is an independent predictor of Tp-Te interval