Characteristics and outcomes in patients with acute myocardial infarction with ST-segment depression on initial electrocardiogram

Background Acute myocardial infarction (AMI) with nonreciprocal ST-segment depression is said to have a poor prognosis, and early diagnosis and treatment are problematic. The aim of this study was to determine the proportion of unselected consecutive patients admitted to a university center with AMI with nonreciprocal ST-segment depression and to characterize these patients in terms of clinical features, treatment, and short- and long-term prognoses. Methods and Results Admission electrocardiographic data on B52 consecutive admissions with AMI were analyzed. Nonreciprocal ST-depression was an admitting feature in 95 (11%) patients, the majority of whom had ST depression>3 mm. These were older (70.3 vs 66.8 years, P <.05), more likely to have had myocardial infarction (40% vs 25%, P <.01), and to have left ventricular failure (56% vs 42%, P <.5), cardiogenic shock (15% vs 9% P =.06), and atrial fibrillation (34% vs 19%, P <.01). Hospital mortality rate was significantly higher (31 % vs 17%, P <.01). Patients were less likely to undergo thrombolysis (17% vs 31%, P <.01), angiography (22% vs 35%, P <.05), or percutaneous revascularization (5% vs 9%, P <.01). Patients with ST depression undergoing coronary angiography were more likely to have 3-vessel disease (71 % vs 47%, P <.05). Mortality rate at follow-up (median 36 months) was significantly higher in patients with ST depression (56% vs 32%, P <.001). Analysis by individual electrocardiography demonstrated ST-segment depression to be the third most frequent presentation after ST elevation (n = 327) and T-wave changes (n = 258), in whom hospital mortality rates were 24% and 9%, respectively. In multivariate analysis, previous myocardial infarction was an independent predictor of nonreciprocal ST depression at initial examination (odds ratio 2.04 [1.25 to 3.34], P <.005). No electrocardiographic presentation was an independent predictor of death in the hospital after AMI. Conclusions In unselected cases of AMI, patients with ST-segment depression make up a significant minority (11%), who are likely to be older with a high prevalence of previous myocardial infarction and multivessel disease, and who have a poor prognosis.