The outcome of patients with a first non-Q wave acute myocardial infarction presenting with ST segment depression, ST segment elevation, or no ST deviations on the admission electrocardiogram

We evaluated the prognosis of patients with a first non-Q wave myocardial infarction according to their admission electrocardiogram. Hospital and 1-year mortality rates in patients with ST elevation (15%, and 21% respectively) and ST depression (17%, and 27% respectively) were similar and significantly higher than in patients with no ST changes (3%, and 10% respectively). Likewise, the adjusted hospital and I-year mortality risks of patients with ST elevation or depression were comparable but higher than the corresponding mortality risk of patients with no ST deviations. The cumulative 5-year mortality rate was highest among patients with ST segment depression (51%) compared to patients with ST elevation (34%) or no ST deviation (21%), (p<0.001 for both comparisons). The adjusted 5-year mortality risk of patients with ST depression was higher (HR: 1.83, 95% C.I., 1.17-2.83) compared to patients with baseline ST elevation (HR-1.33, 95% C.I., 0.83-2.12) or patients with no ST changes (reference group). Patients with baseline ST segment elevation and coexistent ST segment depression in other electrocardiogram leads, had a higher in-hospital mortality rate (19%) compared to counterparts without concomitant ST depression (10%) and a tendency for higher in-hospital mortality risk but not for subsequent 1- and 5-year mortality risks. Conclusions: Patients with a first non-Q wave MI with ST elevation or depression on admission have similar hospital and 1-year mortality risk, but the long-term mortality risk is higher among patients with ST segment depression. Patients with ST elevation and concomitant ST segment depression are at increased risk for mortality during the index hospitalization. (C) 1998 Elsevier Science ireland Ltd. All rights reserved.