The role of multiparametric cardiac magnetic resonance in myocardial infarction with non obstructive coronary arteries: a single - center cohort study

Abstract Background Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a heterogeneous condition with diverse underlying pathophysiological mechanisms. Multiparametric cardiac magnetic resonance (CMR) has emerged as a pivotal diagnostic tool, enabling precise tissue characterization, identification of alternative diagnoses, and prognostic assessment. Purpose This study aimed to evaluate the diagnostic and prognostic yield of multiparametric CMR in patients with suspected MINOCA and assess its impact on clinical reclassification. Methods We conducted a retrospective cohort study including 62 patients diagnosed with MINOCA according to European Society of Cardiology (ESC) criteria who underwent CMR in our Institution, between February 2021 and October 2024. CMR findings were analyzed to confirm or reclassify the MINOCA diagnosis, and all patients underwent a follow-up visit. Patients were categorized based on their final CMR diagnosis. Medical history, clinical characteristics, ECG findings, echocardiographic data, and CMR parameters were then compared across groups. Results Multiparametric CMR provided a definitive diagnosis in all cases. MINOCA was confirmed in 48.4% of patients, while 9.7% had normal findings. Alternative diagnoses were identified in 41.9% of cases, with Takotsubo syndrome being the most frequent (27.4%), followed by myocarditis (4.8%) and other cardiomyopathies, including arrhythmogenic cardiomyopathy (3.2%), non-dilated left ventricular cardiomyopathy (2 patients, 3.2%), cardiac sarcoidosis (1 patient, 1.6%), and inflammatory cardiomyopathy (1 patient, 1.6%). Our cohort exhibited a higher diagnostic yield than previous studies, likely due to the rigorous selection of patients with high clinical suspicion of MINOCA, excluding those with a high pre-test probability of being ‘MINOCA mimics.’ Conclusion Multiparametric CMR plays a crucial role in the diagnostic workup of MINOCA, particularly when preceded by careful patient selection.Mann-Whitney test on T1 mapping values Proportion of patients with LGE