Predictors of left ventricular ejection function decline in young patients with ST-segment elevation myocardial infarction

OBJECTIVE: A decrease in the left ventricular ejection fraction (≤40%) in the setting of ST-segment elevation myocardial infarction is a significant predictor of mortality in the young ST-segment elevation myocardial infarction population. In this study, we aimed to investigate the predictors of left ventricular ejection fraction reduction and evaluate the long-term mortality rates in young ST-segment elevation myocardial infarction patients with or without decreased left ventricular ejection fraction. METHODS: We enrolled retrospectively 411 consecutive ST-segment elevation myocardial infarction patients aged 45 years or below who underwent primary percutaneous coronary intervention. Young ST-segment elevation myocardial infarction patients were divided into two groups according to their left ventricular ejection fraction (≤40%, n=72 and >40%, n=339), which were compared with each other. RESULTS: Statin use, white blood cell count, C-reactive protein, peak creatine kinase-MB, prolonged ischemia time, left anterior descending artery-related infarction, proximally/ostial located lesion, and no-reflow were independently associated with low left ventricular ejection fraction. Additionally, long-term mortality was considerably higher in the left ventricular ejection fraction ≤40% group than those in the left ventricular ejection fraction>40% group (18.1% versus 2.4%; p<0.001). CONCLUSIONS: In young ST-segment elevation myocardial infarction patients, lesion properties (left anterior descending lesion, proximally located lesion), no-reflow, and prolonged ischemia time appeared to be important determinants for the left ventricular ejection fraction decline, rather than coronary disease severity or demographic and hematological parameters. Statin use may be preventive in the development of left ventricular ejection fraction decline in young ST-segment elevation myocardial infarction patients.