[Prognostic significance of signal averaged electrocardiogram in survivors after myocardial infarction].

We evaluated the relationships between the prognosis and the presence of late potentials (LP) on signal averaged electrocardiogram (SAE) in 165 patients surviving an acute myocardial infarction (MI). SAE was performed four weeks after the onset of MI. Arrhythmic events was defined as nonsustained ventricular tachycardia (VT), sustained VT and ventricular fibrillation. LP was detected in 41 (25%) of 165 patients. Patients with LP had dilated left ventricle and lower ejection fraction. At a mean follow-up of 4.4 years, 6 of 124 patients (5%) without LP and 20 of 41 patients (49%) with LP had a late arrhythmic event. Arrhythmic death and sudden death were observed in 2 patients (2%) without LP and in 9 patients (22%) with LP.