Prediction of long-term major events soon after a first ST-segment elevation myocardial infarction by cardiovascular magnetic resonance

• CMR allows the simultaneous and accurate assessment of a variety of variables that include LVEF, IS, edema, hemorrhage, microvascular obstruction, and myocardial salvage.
• CMR predicts the occurrence of ME soon after a first reperfused STEMI.
• A combined assessment of LVEF and IS contributes the most valuable prognostic information.

BackgroundCardiovascular magnetic resonance (CMR) predicts combined clinical events in post-ST-segment elevation myocardial infarction (STEMI) patients. However, its contribution to predicting long-term major events (ME: cardiac death and non-fatal myocardial infarction [MI]) is unknown. We aimed to assess whether CMR predicts long-term MEs when performed soon after STEMI.Methods and resultsWe prospectively recruited 546 STEMI patients between 2004 and 2012. The Left ventricular (LV) ejection fraction (LVEF,%), infarct size (IS), edema, hemorrhage, microvascular obstruction, and myocardial salvage were quantified by CMR at pre-discharge. During a mean follow-up of 840 days, 57 ME events (10%; 23 cardiac deaths, 34 non-fatal MIs) were documented. Patients with MEs has more depressed LVEFs (p < 0.001), larger ISs (p < 0.001), more extensive edema, hemorrhage, and microvascular obstruction, and lower myocardial salvage (p < 0.05). CMR indexes were dichotomized according to the best cutoff values for predicting ME. In a comprehensive multivariate model, a LVEF < 40% (HR: 2.3; 95% CI [12, 43]; p =  0.009) and an IS > 30% of LV mass (HR: 2.4; 95% CI [13, 44]; p =  0.007) independently doubled the ME risk. The ME risk rates were 6%, 14%, and 30%, respectively (p < 0.001) in patients with both the LVEF ≥ 40% and an IS ≤ 30% of LV mass (n = 393), those with only one altered value (n = 84), and in cases with both the LVEF < 40% and an IS > 30% of LV mass (n = 69). Similar tendencies were observed regarding cardiac deaths (2%, 6%, 14%; p < 0.001) and MI (4%, 8%, 16%; p < 0.001).ConclusionsCMR performed soon after STEMI predicts long-term MEs. Combined analysis of CMR-derived LVEF and IS allows robust stratification of patient outcomes.