Background: Prevention of sudden cardiac death on the basis of left ventricular ejection fraction (LVEF) alone is inefficient. Microvolt T-wave alternans (TWA) and electrophysiological study (EPS) has been proposed as useful tools in identifying patients unlikely to benefit from prophylaxis implantable cardioverter-defibrillator (ICD). The purpose of this trial was to determine whether TWA and EPS either one or both predict ventricular tachyarrhythmic events (VTEs) in post-myocardial infarction patients.
Methods: This trail is a one center prospective study enrolled patients with ischemic cardiomyopathy with LVEF≤40%. All patients underwent EPS and some had also TWA. ICDs were mandated if either test was positive.
Results: These are preliminary results. Analyses were conducted on 178 patients followed for a median of 19 months (84% male; average age of 66±8.9 years; LVEF of 31.1±6.5% and NYHA of 2.4±0.61). 127/178 (71%) had positive EPS and 34/60 had positive TWA. 16/127(12.6%) with positive EPS compared to 0/51(0%) with negative EPS had an ICD therapy (ATP and/or shock), p
Conclusions: Among ischemic cardiomyopathy patients with EF≤40%, an abnormal EPS test is associated with higher risk of arrhythmias. Combined positive EPS and TWA identify a subgroup with significantly higher risk for arrhythmias. Patients with normal EPS and or TWA have a very good prognosis and are likely to benefit little from ICD therapy.
