Magnetic Resonance Imaging in prognostic stratification of patients with Acute Myocardial Infarction

Purpose: The purpose of this study was to verify the role of cardiac magnetic resonance imaging in prognostic stratification of patients with acute myocardial infarction (STEMI) treated with primary angioplasty (PCI). Materials and Methods: During the years 2012 and 2013, 36 patients treated with primary angioplasty were selected in order to be examined with magnetic resonance imaging in acute stage (within 6 days) and at a later stage after 6-7 months. The MR protocol included SSFP sequences, T2Black-Blood FAT SAT for edema evaluation and contrastographic IRGE sequences for the evaluation of delayed enhancement. The ejection fraction in acute and follow-up was considered as the fundamental parameter of prognostic stratification. In addition, by using post-processing dedicated tools, the following data was extrapolated: the end-diastolic volume, the amount of edema and scar, then correlated to the ejection fraction. Results: In acute phase, the end-diastolic volume, edema and the delayed enhancement (DE) presented variable correlation with ejection fraction (r = 0.58, and 0.80 0.69); while after 6 months, the correlation between the end-diastolic volume, delayed enhancement and ejection fraction was 0.64 and 0.87. None of the patients presented edema in chronic phase. Conclusions: The data of our study suggest that MRI is an important prognostic stratification tool in patients with STEMI, especially for the significant correlation between ejection fraction and the amount of delayed enhancement.