A SIMPLE ELECTROCARDIOGRAPHIC PREDICTOR OF THE OUTCOME OF PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION TREATED WITH A THROMBOLYTIC AGENT - A -STUDIO-DELLA-SOPRAVVIVENZA-NELLINFARTO-MIOCARDICO (GISSI-2)-DERIVED ANALYSIS

Objectives. This analysis aimed to evaluate in a large patient cohort the relation between ST segment alterations after fibrinolytic therapy for acute myocardial infarction and 1) the combined end point of in-h ospital mortality plus clinical congestive heart failure or extensive left ventricular damage, and 2) mortality 30 and 180 days after random ization. Background. Angina relief, enzyme release acceleration and ST segment normalization are related to coronary artery reperfusion and prognosis. Electrocardiographic (ECG) evaluation before and after fibr inolytic drug administration has been used to predict short-and long-t erm clinical outcome in acute myocardial infarction. Methods. Patients enrolled in the Gruppo Italiano per lo Studio della Sopravvivenza nel l'Infarto Miocardico (GISSI-2) trial underwent a standard ECG on admis sion and after 4 h of alteplase or streptokinase therapy; 7,426 record ings were suitable for ST segment analysis. A decrease greater than or equal to 50% in the sum of ST segment elevation in all ECG leads was adopted as the cutoff for predicting coronary artery patency. Recanali zation was deemed to have occurred in 4,951 patients (group A) versus 2,475 patients without reperfusion (group B). Results. Group A patient s experienced a lower incidence of the combined end point than did gro up B patients (16.2% vs. 22.9%, respectively), as well as of all its c omponents (death, clinical heart failure, ejection fraction <35%, inju red myocardial segment >45%, QRS score >10). Thirty- and 180-day morta lity rates were lower in group A than group B (3.5% and 5.7% vs. 7.4% and 9.9%, respectively); relative risk (Cox) was 0.46 (95% confidence interval [CI] 0.37 to 0.57) for 30-day and 0.58 (95% CI 0.48 to 0.70) for 180 day mortality. Patients in group A had significantly less vent ricular fibrillation and sustained ventricular tachycardia but more is chemic episodes (early recurrent angina plus myocardial infarction rec urrence). Conclusions. A simple, inexpensive instrumental evaluation, unaffected by different epidemiologic and clinical characteristics of the population analyzed, can allow early assessment of the effectivene ss of fibrinolytic treatment with respect to the main clinical outcome s.