The mortality predictive power of discharge electrocardiogram after first acute myocardial infarction.

The prognostic value of discharge ECG was studied in 457 patients after their first acute myocardial infarction. Thirteen different ECG variables were studied on the discharge ECG. When cumulative 4-year survival rates were calculated by standard life-table method for each variable individually, the following variables had statistically significant prognostic power: PTF (P terminal force), PTFA (P terminal frontal axis), AF (atrial fibrillation), ST depression, ST elevation, QRS duration, and the combination block (LBBB/RBBB + LAHB/LPHB). The variables with no statistically significant predictive power were: QTc, LBBB or RBBB, LAHB or LPHB, AV block, T wave angle, T negativity, and sigma R. The relative risks for the most important variables in the discrete life-table model were: PTF 3.4, QRS duration 3.3, ST depression 2.6, PTFA 2.5, and ST elevation 2.2. In further analysis a model with only three ECG variables (PTF, ST depression, and ST elevation) was developed which stratified the study population in categories with 1.9% to 75.5% estimated 4-year survival rates.