The Relationship between Tpeak-end Interval Duration and Tpeak-end/QT Ratio, and Arrhythmias in Patients with Coronary Slow Flow

Background: Coronary Slow Flow (CSF) is described as delayed opacification of the distal vasculature and angiographically Normal Coronary Arteries (NCA). Numerous studies have suggested that the interval from the peak to the end of electrocardiographic T wave (Tp-e) may correspond to transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias.

Objectives: The present study aimed to evaluate ventricular repolarization in patients with CSFby using Tp-e interval and Tp--e/QT ratio.

Patients and Methods: This study was conducted on electrocardiographic parameters of 100 patients with angiographically proven NCA with CSF in all three coronary arteries and 100 patients with NCA without CSF. The patients were followed up for arrhythmias and clinical events.

Results: Tp–e tail interval (120 ± 5.5 msn, 101 ± 3.9 msn; P < 0.001), Tp–e tangent interval (99 ± 4.0 msn, 78 ± 3.0 msn, P < 0.001), Tp-e tail/QT ratio (0.31 ± 0.004, 0.26 ± 0.003, P < 0.001), and Tp-e tangent/QT ratio (0.25 ± 0.003, 0.19 ± 0.003, P < 0.001) were significantly higher in the CSF patients compared to the NCA group. Rhythm holter analyses also showed that ventricular extrasystoles were higher (157 ± 22.5, 87 ± 11.9, P = 0.002) in the CSF group compared to the NCA group.

Conclusions: Tp-e interval and Tp-e/QT ratio were significantly higher in the patients with CSF compared to the NCA group.