Document Type : Original Article

Author

Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia.

Abstract

Background: The increased Tpe/QT ratio is a novel, promising predictor of cardiac arrhythmias. However, no consensus exists regarding the Tpe/QT measurement. This study aimed to evaluate Tpe/QT variability among standard ECG leads.
 
Methods: Tpe/QT magnitudes were analyzed in 8 standard ECG leads (I, II, V1–V6) in 33 patients with a definite diagnosis of arrhythmogenic right ventricular cardiomyopathy. Tpe/QT values were calculated in several ways: averaging against 1 or more leads over all the patients and searching the maximum value among all measured leads in each patient (the true maximum), followed by averaging over all the patients.
 
Results: Maximum and minimum Tpe/QT values were distributed among all the tested ECG leads. In each lead, minimum and maximum Tpe/QT values could be observed in different patients. The dispersion of Tpe/QT magnitudes calculated in various ways reached the value of 0.055.
 
Conclusions: The Tpe/QT magnitude depends on the method of determining the T-wave ending and the number of ECG leads used for its calculation. To detect the increased Tpe/QT ratio, the analysis of all available ECG leads against 1 or a few leads is preferable. (Iranian Heart Journal 2024; 25(2): 75-80)

Keywords