Evaluation of the Tp-Te interval, Tp-Te/QTc ratio, and QT dispersion in patients with Turner syndrome

Objective: To evaluate ventricular repolarization parameters using the interval from the peak to the end of the T wave (Tp-Te), together with QT and corrected QT (QTc) intervals, QT dispersion (QTd), and Tp-Te/QTc ratio in patients with Turner syndrome (pwTS) and to compare the results with those from healthy controls. Methods: In total, 38 patients previously diagnosed with Turner syndrome (TS) and 35 healthy girls (controls) were included in our cross-sectional study. Twelve-lead electrocardiography (ECG) and echocardiography after a 30-min rest were performed. The QT, QTc, QTd, Tp-Te interval, and Tp-Te/QTc ratio were determined. Results: No differences in age or sex were observed between the groups. QT intervals were similar in both groups [pwTS: 354.76 +/- 25.33 ms, controls (C): 353.29 +/- 17.51 ms, p=0.775]. pwTS had significantly longer QTc and QTd than controls (411.87 +/- 22.66 ms vs. 392.06 +/- 13.21 ms, p<0.001 and 40.31 +/- 2.02 ms vs. 37.54 +/- 1.83 ms, p<0.001, respectively). Similarly, the Tp-Te interval and Tp-Te/QTc ratio were significantly longer in pwTS than in controls (71.89 +/- 3.39 ms vs. 65.34 +/- 2.88 ms, p<0.001 and 0.17 +/- 0.01 vs. 0.16 +/- 0.01, p=0.01). Conclusion: As pwTS have longer QTc, QTd, Tp-Te interval, and Tp-Te/QTc ratio, an annual follow-up with ECG can provide awareness and even prevent sudden death in them. Also avoiding the use of drugs that makes repolarization anomaly and having knowledge about the side effects of these drugs are essential in pwTS.