The indices of ventricular repolarization heterogeneity may be used as diagnostic criteria for left ventricular hypertrophy in patients with arterial hypertension. Analyzing the variability of T-wave amplitudes and repolarization integrals

Background. The values of ventricular repolarization variability are higher in patients with hypertensive left ventricular hypertrophy (LVii) and (hey correlate with the left ventricular myocardial mass index (LVMMl). Objective. To develop diagnostic criteria for LVH, which are based on the analysis of the values of ventricular repolarization heterogeneity, the indices of the variability of a T-wave amplitude. Subjects and methods. The study included 69 patients with arterial hypertension and 20 patients without cardiovascular diseases who were divided, on the basis of echocardiography determination of LVMMI into groups with or without LVH. The par of the variability of repolarization parameters were analyzed. These included dispersion (Disp), normalized dispersion (Dispnorm), root mean square deviation (RMSD) of T-wave amplitude, as well as total repolarization integrals (TRI, a product of JT_end interval, and the T-wave amplitude), early repolarization integrals (ERI, a product of the JT_apex interval, and the T-wave amplitude,) late repolarization integrals (LRI, a product of the T_apex - T_end interval, and the T-wave amplitude.) of EGG leads 12 and V₁-V₆. Results. An analysis of V₁-V₆ leads has indicated that as compared to male patients with normal l.VMMI. the males with I.VII had higher values of T-wave amplitude variability and increased values of the variability of total and early repolarization integrals (of Disp, Dispnorm and RMSD), which correlated with LVMMI. A regression analysis has shown that LVMMI was an independent predictor of the dispersion of T-wave amplitudes and that of the variability of Disp, Dispnorm, of TRI, the relative thickness of the walls of the left ventricle is an independent predictor of Dispnorm and RMSD of T-wave amplitudes, as well RMSDo f TRI and ERI variability. The best diagnostic characteristics were demonstrated by RMSD of T_amp of ≥ 37 ms (39 % sensitivity, 91 % specificity, 86 % positive predictive value, and 51 % negative predictive value) and Dispnorm of TRI of ≥ 300 mV x msec (45 % sensitivity, 91 % specificity, 88 % positive predictive value, and 54 % negative predictive value). These characteristics were comparable with those for the Cornell criteria, but they were less than those for the Sokolov-Lyons criteria in sensitivity. In females with LVH, the values of the variability of T-wave amplitudes and repolarization integrals did not differ from those with normal LVMMI. The correlation of LVMMI and the values of the variability of T-wave amplitudes and repolarization integrals was insignificant. Conclusion. The values of the amplitude heterogeneity of ventricular repolarization and variability of repolarization integrals may be used as independent criteria of LVH in males with arterial hypertension.

ventricular repolarization variability index, left ventricular hypertrophy, arterial hypertension

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