Ten-year prognostic impact of cardiac magnetic resonance endpoints in patients with ST-segment elevation myocardial infarction

AIMS: The study aimed to investigate the importance of infarct size (IS), microvascular obstruction (MVO), and myocardial salvage index (MSI) on the 10-year outcome in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS: Patients with STEMI had cardiac magnetic resonance (CMR) performed during admission and after 3 months to assess acute and 3-month IS, MSI, left ventricular ejection fraction (LVEF), MVO and transmurality. Adjusted Cox regression models were used to investigate the association between CMR endpoints and all-cause mortality or hospitalization for heart failure 10 years after STEMI. A total of 811 patients had either acute or follow-up CMR performed. During median follow-up of 10.9 years, 173 (21%) patients died or were hospitalized for heart failure. Acute IS [adjusted hazard ratio (HR): 1.02; 95%-confidence interval (CI): 1.01-1.04; P = 0.005], 3-month IS (adjusted HR: 1.04; 95%-CI: 1.02-1.06; P < 0.001), acute MSI (adjusted HR: 0.99; 95%-CI: 0.98-1.00; P = 0.007), 3-month MSI (adjusted HR: 0.99; 95%-CI: 0.98-1.00; P = 0.004), acute LVEF (adjusted HR: 0.97; 95%-CI: 0.95-0.99; P = 0.001), 3-month LVEF (adjusted HR: 0.95; 95%-CI: 0.93-0.97; P < 0.001), acute transmurality (adjusted HR: 1.01; 95%-CI: 1.00-1.02; P = 0.024), and 3-month transmurality (adjusted HR: 1.01; 95%-CI: 1.00-1.02; P = 0.003) were all significant predictors of the composite outcome. MVO was not associated with the composite outcome (adjusted HR: 1.04; 95%-CI: 0.98-1.09; P = 0.20).

CONCLUSION: Smaller IS, smaller transmurality, higher MSI, and higher LVEF measured acutely and 3 months after STEMI were independently associated with lower all-cause mortality and/or hospitalization for heart failure within 10 years after STEMI, whereas MVO was not.

CLINICAL TRIAL REGISTRATION: Registered with ClinicalTrials.gov (identifiers: NCT01435408 and NCT01960933).