Myocardial infarction with non-obstructive coronary arteries (MINOCA) in Chinese patients: Clinical features, treatment and 1 year follow-up.

Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is characterised by clinical evidence of myocardial infarction with normal or near-normal coronary arteries on angiography (stenosis<50%). We investigated clinical features among Chinese MINOCA patients and one-year follow-up on medication management and cardiovascular events.

Methods: The data of 2029 patients with acute myocardial infarction were consecutively collected. MINOCA patients were identified with coronary angiography (<50% stenosis). Clinical features, medication management and cardiovascular events were assessed.

Results: One hundred and twenty-eight patients (6.3%) were diagnosed as MINOCA. Compared with the myocardial infarction with obstructive coronary arteries (MI-CAD) patients, the prevalence of traditional risk factors of CAD was lower in MINOCA patients. The levels of TG, LDL-C, cTnT, CK-MB and myoglobin in the MINOCA group were significantly lower, whereas LVEF was higher. MINOCA patients are less likely to receive secondary prevention medication for MI, and use of all recommended drugs decreased at one-year follow-up. MACE in the MINOCA group was lower. After adjusting related risk factors, logistic analysis showed MINOCA was independently associated with lower risk of MACE. Independent predictors for MACE in MINOCA patients were older age (≥60 years), females, atrial fibrillation and reduced LVEF.

Conclusion: Compared with MI-CAD, MINOCA was accompanied by fewer traditional risk factors of CAD, less likely to be discharged upon secondary prevention medication of MI and the occurrence of MACE during 1 year follow-up was lower. Older age (≥60 years), females, atrial fibrillation and reduced LVEF were independent risk factors for MACE in MINOCA patients within one year.