Journal List > Korean Circ J > v.35(8) > 1016016

TOOLS
Hwang, Jun, Choi, Yoo, Ahn, Choi, Choi, Zhen, Choi, Choi, Yoon, Shin, and Tahk: Efficacy of T-Wave Alternans for the Prediction of Lethal Arrhythmic Events after Myocardial Infarction
Original Article
Korean Circulation Journal

Korean Circulation Journal 2005; 35(8): 597-604.

Published online: 31 August 2005

DOI: https://doi.org/10.4070/kcj.2005.35.8.597

Efficacy of T-Wave Alternans for the Prediction of Lethal Arrhythmic Events after Myocardial Infarction

Gyo Seung Hwang, Dae Geun Jun, Un Jung Choi, Sang Young Yoo, Sung Gyun Ahn, Jung Hyun Choi, Byoung Joo Choi, Zhen Guo Zhen, Tae Young Choi, So Yeon Choi, Myeong Ho Yoon, Joon Han Shin, Seung Jea Tahk

Department of Cardiology, Ajou University School of Medicine, Suwon, Korea.

Department of Biomedical Engineering, The Graduate School, Yonsei University, Seoul, Korea.

hwanggs@ajou.ac.kr

Copyright © 2005 The Korean Society of Circulation

Abstract

BACKGROUND AND OBJECTIVES: The prevention of sudden death in patients with a myocardial infarction (MI) remains the therapeutic target. T-wave alternans is as a heart rate dependent measure of repolarization, which correlates with ventricular arrhythmia vulnerability. The goals of this study were to clarify whether microvolt-level T-wave alternans (mTWA) can predict lethal arrhythmic events, and compare their role with other risk indices in predicting lethal events following a MI.
SUBJECTS AND METHODS: The mTWA was analyzed in 78 MI patients, using a power-spectral method during bicycle exercise testing. Additionally, the left ventricular ejection fraction (EF), late potentials (LP) and heart rate variability were also measured.
RESULTS: The mTWA was positive in 16 patients (21%), negative in 36 (46%) and indeterminate in 21 (33%). Lethal arrhythmic events developed in 7 patients (3 sudden deaths, 3 ventricular tachycardia and 1 ventricular fibrillation), during a mean follow-up of 12±3 months. The event rate was significantly higher in patients with a positive mTWA (relative risk 12.0, 95% CI 1.2 to 118.1, p=0.01) or lower EF (<40%)(relative risk 11.0, CI 1.9 to 65.0, p=0.002). The mTWA test exhibited the highest sensitivity, relative risk and negative predictive value, but the lowest specificity; positive predictive values were observed compared with the EF or a combination of the two indices.
CONCLUSION: mTWA was closely related to the occurrence of lethal arrhythmic events in patients with a MI. Therefore, mTWA with a lower EF could be a useful screening test for the prediction of potentially lethal arrhythmic events following a MI.

Keywords: Myocardial infarction, Sudden cardiac death, Tachycardia, ventricular, Ventricular fibrillation

TOOLS
Similar articles