Objective To analyze the risk factors of morbidity, clinical manifestations, and short-term prognosis of non-obstructive coronary myocardial infarction (MINOCA).

Methods Totally, 838 patients with myocardial infarction who underwent coronary angiography in the Cardiac Intervention Center of Zhongshan Hospital, Fudan University from March 2020 to March 2021 were included. There were 77 MINOCA patients and 761 myocardial infarction patients complicated with obstructive coronary artery disease (MI-CAD). The high-risk factors, laboratory indexes, ECG, echocardiography, and the incidence of adverse events were compared between the two groups.

Results The proportions of males, hypertension, diabetes, and smoking in the MINOCA group were lower than those in the MI-CAD group (P < 0.05). The levels of troponin T, N-terminal pro-brain natriuretic peptide (NT-proBNP), white blood cell count, and neutrophil count were lower in the MINOCA group than those in the MI-CAD group (P < 0.001). The proportions of ST-segment elevation, abnormal wall systolic activity, and decreased ejection fraction in the MINOCA group were significantly lower than those in the MI-CAD group (P < 0.001). There was no difference in the incidence of adverse events between the two groups.

Conclusions The incidence of MINOCA has no obvious gender tendency, the risk factors of MI-CAD are different from those of MI-CAD, and MINOCA patients have milder cardiac damage and better short-term prognosis.