Since its initial description, a number of studies have described the use of microvolt T-wave alternans (MTWA) as a predictor of the primary or secondary occurrence of ventricular arrhythmic events. These studies, however, have been limited by small sample sizes and disparate patient populations. Studies of MTWA in post-myocardial infarction (MI) patients are few in number, but hold predictive value for risk of ventricular arrhythmias. We performed a study of MTWA in post-myocardial infarction patients to clarify the predictive accuracy and usefulness of MTWA compared to other invasive and non-invasive techniques. We enrolled 120 patients (74 men, 46 women, mean age 62.3 ± 15.2 years in men, and 64.2 ± 13.8 years in women) with a history of myocardial infarction but no prior sustained ventricular arrhythmias. Patients were assessed by echocardiography, Holter, signal averaged ECG, MTWA, and electrophysiology study. Mean follow-up was 14 months. The MTWA test had a good negative predictive value for arrhythmic events in post-MI patients and can be used for risk stratification. We consider that in patients with positive MTWA further invasive evaluation, respectively electrophysiology study, is necessary.
Keywords: T-wave alternans; risk stratification; sudden death; ventricular arrhythmias.