Abstract
BACKGROUND: Patients with successful reperfusion and preserved left ventricular ejection fraction (LVEF) after ST-segment myocardial infarction (STEMI)have always been thought to have low risk for adverse events. Great interest is focused on finding simple, noninvasive tools to refine risk stratification among them. OBJECTIVES: We hypothesized that degree of ST-segment resolution (STR) after STEMI can identify high-risk group among patients with LVEF ≥ 50% following STEMI. METHODS: During the period from January to July 2017, patients with successful reperfusion of STEMI and LVEF ≥ 50% were prospectively included. Patients were divided into two groups based on the percent of ST segment resolution using single lead STR method; group I (complete STR ≥ 70%) and group II (partial STR 50%-70%). The endpoint was a composite of cardiovascular mortality, re-hospitalization for heart failure and urgent revascularization at 30-day. RESULTS: After exclusion, 110 patients were left for final analysis. No significant differences in all baseline characteristics were found between both groups. The primary endpoint occurred in seven patients (12.7%) of group I versus 17 patients (30.9%) of group II (Relative risk = 2.43, 95%CI = 1.1-5.4, p = 0.021) driven by a significant reduction in rates of re-hospitalization due to heart failure. A multivariate logistic regression analysis showed incomplete STR to be a significant independent predictor for 30-dayMACEs (OR 3.25, 95% CI1.2-8.83, p = 0.02) even after adjustment for location of infarction. CONCLUSION: Complete STR predicts 30-day outcome in patients with preserved LVEF following successful reperfusion of STEMI.