Prognosis following acute myocardial infarction in patients with ST-T abnormalities on electrocardiograms obtained before myocardial infarction

Background: Many studies have examined the relationship between prognosis a fter myocardial infarction (MI) and electrocardiographic (ECG) findings at the time of or after the onset of MI. However, little work has been done co ncerning the association between ECG findings obtained before the onset of MI. (pre-MI) and the prognosis after MI. Hypothesis: The study was undertaken to determine whether ST-T segment and T-wave morphology on pre-MT ECGs provides useful information for prognosis after acute MT. Methods: Pre-MI ECGs of 212 patients recorded within the 6-month period bef ore MI were studied for the presence of high-voltage R waves, ST-segment de pression, and negative T waves. The Kaplan-Meier method and multivariate an alysis were used to determine the relationship between these ECG findings a nd in-hospital cardiac death. Results: In-hospital cardiac death occurred in 32 (15.1%) patients. The in- hospital mortality rate was 38.5% (5/13) for the patients with high-voltage R waves, 54.5% (6/11) for patients with ST-segment depression, and 45.6% ( 15/33) for patients with negative T waves. The in-hospital mortality rate w as 13.6% (27/199) for patients without high-voltage R waves, 12.9% (26/201) for patients without ST-segment depression, and 9.5% (17/179) for those wi thout negative T waves. Multivariate analysis identified age and negative T waves as independent risk factors for cardiac death, with a hazard ratio f or negative T waves of 3.1. Conclusion: Negative T waves on pre-MI ECGs represent an independent predic tor of in-hospital cardiac death in patients with MT.