Cardiac magnetic resonance imaging in myocardial infarction with non-obstructed coronary arteries: diagnostic and prognostic value

Myocardial infarction with non-obstructed coronary arteries (MINOCA) occurs when patients experience a heart attack without significant coronary artery blockage despite showing acute coronary syndrome symptoms. Unlike stable atherosclerosis, MINOCA involves acute myocardial infarction (MI) without obstructive coronary artery disease (CAD). The diagnostic criteria included meeting the universal MI definition, non-obstructive coronary arteries on angiography (< 50% stenosis), and no apparent cause of the acute event. The causes include coronary, cardiac, and extracardiac origins, such as plaque rupture, coronary spasm, myocarditis, or pulmonary embolism. MINOCA affects 5-6% of patients with acute MI undergoing angiography, with variations based on demographic factors. Although MINOCA was initially believed to have a favorable outcome, recent findings have indicated that MINOCA patients have a worse prognosis than the general population. Current guidelines strongly advocate the use of cardiac magnetic resonance imaging (CMR) to evaluate suspected MINOCA cases. However, multiple studies have demonstrated that CMR may fail to detect some instances of MINOCA, particularly in cases of mild inflammation or minor infractions. This could lead to a false-negative diagnosis requiring further testing. This review aimed to evaluate the diagnostic and prognostic value of CMR in patients with potential MINOCA.