Myocardial infarction with non-obstructive coronary arteries (
MINOCA) is a heterogeneous and diverse disease entity, which accounts for about 6 % of all acute
myocardial infarction (AMI) cases. In patients with
chest pain and acute myocardial injury detected by a highly sensitive
troponin assay, the absence of epicardial
coronary stenosis of 50 % or greater on angiography leads to the working diagnosis of
MINOCA. The updated JCS/CVIT/JCC 2023 Guideline described
MINOCA as a new disease concept and recommended a multimodality approach to uncovering the underlying causes of
MINOCA. Cardiac magnetic resonance (CMR) is useful in not only making a definite diagnosis of
MINOCA, but also excluding non-ischemic causes that mimic AMI such as
takotsubo cardiomyopathy and
myocarditis. Meanwhile, intracoronary imaging, particularly optical coherence tomography (OCT), enables us to evaluate precisely intracoronary morphological alterations including plaque disruption and
spontaneous coronary artery dissection which are not revealed by angiographic findings alone. Recent studies have shown that an initial workup with the combination of CMR and OCT could provide a definite diagnosis in a significant percentage of patients suspected of
MINOCA. Consecutively, patients with inconclusive results of a series of CMR and OCT implementation are eligible for assessing the potential for coronary functional abnormalities or blood coagulopathy as another factor involved in the development of
MINOCA. Although uncovering the pathogenesis of
MINOCA might be essential for establishing an individualized treatment approach, significant knowledge gaps in terms of
secondary prevention strategies for
MINOCA focusing on the improvement of long-term prognosis remain to be overcome. In this review, we summarize our current understanding of
MINOCA and highlight contemporary diagnostic approaches for patients with suspected
MINOCA.