Background: It remains controversial whether cardiac strain accurately predicts adverse events after acute ST-segment elevation myocardial infarction (STEMI). The aim of the present study was to evaluate the effects of cardiac strain revealed on cardiac magnetic resonance (CMR) imaging on cardiac events and adverse left ventricular (LV) remodeling.Methods: Between February 2015 and September 2016, we conducted a prospective two-center cohort study of patients with STEMI treated with primary percutaneous coronary intervention comprising stent implantation. All included patients underwent CMR imaging before discharge. Major adverse cardiac events (MACE) and LV remodeling were assessed during 6 months of follow-up.Results: Seventy-six patients were available for the final analysis. The MACE rate was 23.7%, using cardiac death, reinfarction, unplanned revascularization, and heart failure as combined events during 6 months of follow-up. The global longitudinal strain (GLS) was an independent predictor of MACE (OR=1.21 (1.07–1.36), P=0.002) and LV remodeling (OR=2.06 (1.14–3.73), P=0.017).Conclusion: In patients with STEMI treated with primary percutaneous coronary intervention, the GLS determined on CMR imaging performed before discharge is a predictor of MACE and adverse LV remodeling during 6 months of follow-up.