Dispersion of repolarization parameters in hypertensive cardiomyopathy

Introduction: The heterogeneity of refractory periods and conduction velocities of adjacent myocardial areas is well known as mechanisms of arrhythmogenesis, the dispersion of ventricular repolarization being described. Aim: Comparison of classical parameters of dispersion of repolarization (QT interval, QT dispersion (dQT)) versus novel ones (T peak-end interval (Tpe), Tpe/QT ratio and Tpe dispersion (dTpe)) in relation to left ventricular geometry and diastolic function in hypertension. Method: 62 patients with grades I and II hypertension, 58% women, age 55 ± 11 years, were evaluated by echocardiography and electrocardiography. Ventricular remodeling was assessed by calculating the left ventricular mass index (LVMI) using Devereux formula and the diastolic function by transmitral E and A wave velocities and E/A ratio. Tpe was defined as the interval between the peak and end of the T wave (in the precordial leads). Results: Parameters that correlated with LVMI were Tpe and Tpe/QT in lead V2 (r = 0.27, p = 0.04, r = 0.33, p = 0.01, respectively) and in lead V3 (r = 0.42 and r = 0.43, respectively, p = 0.001) and dTpe (r = 0.32, p = 0.01). E/A ratio correlated with QT interval (r = -0.39, p = 0.008), Tpe in lead V3 (r = -0.39, p = 0.008), Tpe/ QT in lead V3 (r = -0.36, p = 0.01) and dTpe (r = -0.36, p = 0.01). Conclusions: Novel parameters exploring the dispersion of ventricular repolarization (Tpe interval, Tpe/ QT ratio and Tpe dispersion) seem to be superior to classical ones (QT interval and QT dispersion), correlating with LVMI and E/A ratio. The leads useful for measuring Tpe and Tpe/QT ratio in hypertensive patients appear to be V2 and V3.

ISSN – online: 2734 – 6382
ISSN-L 1220-658X
ISSN – print: 1220-658X
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CODE: 379
CME Credits: 10 (Romanian College of Physicians)