LATE POTENTIALS IN POSTINFARCTION PATIENT S - ARRHYTHMOGENIC RISK ANDCLINICAL CHARACTERISTICS

A prospective study was performed of the correlation of ventricular la te potentials (LP) and clinical parameters in patients after acute myo cardial infarction. To evaluate the prognostic significance of the sig nal averaged-electrocardiogram (SAECG) in risk stratification of sudde n cardiac death and arrhythmogenic events, the clinical characteristic s of these postinfarction patients were performed in a follow-up-perio d. 243 consecutive patients underwent SAECG for detection of late pote ntials in the second week after acute myocardial infarction. After a m ean follow-up of 9 months the patients were asked a standardized quest ionnaire. Late potentials are independent of age, sex, left ventricula r ejection fraction, peak activity of MB fraction of creatine kinase, and the cardiovascular risk factors in postinfarction patients. In pat ients, who received thrombolytic therapy, the incidence of late potent ials is lower (p < 0.05) and in patients with posterior wall infarctio n it is significantly higher (p < 0.04). In the follow-up period patie nts with abnormal SAECG show a significantly higher rate of angina pec toris, palpitations, dizziness, and syncope. By way of contrast, posti nfarction patients with normal SAECG feel mainly comfortable in the fo llow-up (p < 0.01). The mortality was even in both groups. Sudden card iac death in the late postinfarction period shows a significant correl ation with the finding of late potentials in SAECG in the early myocar dial infarction period (p < 0.01). The SAECG for detection of late pot entials as a non-invasive investigation in the early postinfarction pe riod characterizes patients with an arrhythmogenic risk, especially su dden cardiac death, independent of other conventional methods. Further more, the impaired patient with clinical symptoms in the late postinfa rction period is hereby identified.