Mueller C et al. (2004) Prognostic value of the admission electrocardiogram in patients with unstable angina/non-ST-segment elevation myocardial infarction treated with very early revascularization. Am J Med 117: 145–150

A report by Mueller and colleagues has provided new information about the prognostic value of the admission ECG in cases of myocardial ischemia. The study included a cohort of 1,450 consecutive patients with unstable angina/non-ST-segment elevation myocardial infarction (MI), who were assessed by coronary angiography within 24 hours of admission. Patients were divided into three groups according to the presence of new ST-segment depression (n = 136), T-wave inversion (n = 419) or no changes on the admission ECG (n = 895). Revascularization was carried out in the majority of patients (n = 1,066), most often using percutaneous coronary intervention (PCI) with stent placement. Coronary artery bypass grafting was carried out in selected patients. The primary end point was all-cause mortality.

Adjusting for potential confounders, the cumulative death rate at 36 months was significantly higher for patients with ST-segment depression (hazard ratio [HR] 2.2, 95% confidence interval [CI] 1.1–4.6) than for patients with no ECG changes; in contrast, T-wave inversion was associated with a more favorable outcome (HR 0.44, 95% CI 0.20–0.96). Surprisingly, the prognostic value of these ECG changes was similar in men and women.

Mueller et al. conclude that ST-segment depression and T-wave inversion were important prognostic factors in patients undergoing very early revascularization for unstable angina/non-ST-segment elevation MI. It is unclear whether these findings will apply outside the study, where early and aggressive use of PCI may be less common.