RISK ESTIMATION OF T WAVE ALTERNANS AND VENTRICULAR LATE POTENTIALS IN PATIENTS WITH CARDIOMYOPATHY

Abstract

Background: T wave alternans and ventricular late potentials represent repolarization heterogeneity and slowing of cardiac impulse which may lead to ventricular arrhythmias. Cardiomyopathy is a disorder which puts the patients on the risk of sudden arrhythmic death. Present study was designed to evaluate the risk of developing T wave alternans and ventricular late potentials in patients with cardiomyopathy. Methods: This cross-sectional comparative study was carried out at Armed Forces Institute of Cardiology, Rawalpindi from Feb to Aug 2016. Sixty cardiomyopathic patients and 60 healthy controls were recruited through convenience sampling. Ambulatory ECG was recorded by using DMS 300-4L Holters. T wave analysis was done by Cardioscan Premier 12 Lux software. Mortara ELI 350 Electrocardiograph was used to obtain Signal Averaged ECG for analysis of Ventricular Late Potentials. Results: T wave alternans was positive in 13 (21.66%) cardiomyopathic patients while in healthy controls only 4 (6.66%) participants demonstrated positive T wave alternans. Ventricular late potentials were present in 14 (23.33%) cases and 5 (8.33%) healthy controls. The relative risk of having positive T wave alternans and ventricular late potentials was 3.3 and 2.8 times greater respectively in patients with cardiomyopathies as compared to healthy controls. Conclusion: Patients with cardiomyopathy are at higher risk of developing positive T wave alternans and ventricular late potentials. Patients positive for both parameters constitute a high-risk subset for developing ventricular arrhythmias.

Pak J Physiol 2018;14(4):14–7