Abstract

Background: The coronary angiography results in a group of patients with myocardial infarction (MI) are normal or near-normal; which is diagnosed as myocardial infarction with non-obstructive coronary arteries (MINOCA). This study aimed to compare the mortality rate and risk factors between MINOCA and myocardial infarction with obstructive coronary artery (MI-CAD).Methods: This retrospective cohort study was conducted from January 1, 2018, to December 31, 2019. A total of 679 patients admitted to Afshar Hospital in Yazd with a diagnosis of ST-elevation myocardial infarction (STEMI) from 2018-2019 who underwent primary Percutaneous Coronary Intervention (PCI) were enrolled in the study. Demographic, and clinical variables, ECG finding and one-year mortality, were extracted using MI registry data from the Yazd Cardiac Research Center.Results: The estimated frequency of MINOCA was 4.6. Patients with MINOCA (47.14 +/- 6.2) were younger than patients with MI-CAD (57.61 +/- 9.1) (P <0.0001). MINOCA patients (47.4 +/- 9.47) had a considerably greater left ventricular ejection fraction (LVEF) than MI-CAD patients (43.5 +/- 6.8) (P =0.018). The majority site of MI in MINOCA patients was located in the non-anterior wall (p <0.0001). A comparison of MINOCA and MI-CAD patients' one-year mortality revealed no significant difference (P =0.07).Conclusion: The prevalence of patients with MINOCA in Yazd was similar to other communities. Although these patients probably do not have a better prognosis, despite being younger and having better LV systolic function and lower CAD risk factors.