Epidemiological Profile of Myocardial Infarction with Non-Significant Stenosis of Coronary Arteries (MINOCA)

Abstract

Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) remains a puzzling clinical entity characterized by clinical evidence of myocardial infarction (MI) with normal or near-normal coronary arteries on angiography (stenosis < 50%). This pathology is poorly understood, several studies are underway for a better understanding of this disease. The aim of our work was to review the literature and assess the epidemiology, clinical features, prognosis and etiologies of MINOCA. Methods: Descriptive, prospective study, spread over a period of 36 months from January 2018 to December 2020 involving a total number of 585 patients undergoing coronary angiography at the cardiology department of CHU Tlemcen, for a reason for acute myocardial ischemia. We defined the patients as having acute myocardial ischemia with obstructive coronary artery disease (MI-CAD) if there was revascularization or plaque ≥ 50% and as having MINOCA if there was <50% obstruction or a mechanism without plaque. Patients who received thrombolytics before angiography were excluded. We studied the epidemiological, clinical and prognostic profile of the MINOCA population then compared them to patients with obstructive coronary artery disease and finally we established an etiological analysis of the MINOCA population. Results: The number of MINOCA cases in our sample of 585 AMI patients was 10.25% vs. 525 (89.74%) cases of AMI-CO, it was more common in men (78.3% vs. 21, 7%; odds ratio at 3.61) and in the youngest patients. MINOCA patients were more likely to be without traditional cardiac risk factors (7.9% vs. 2.1%; P <0.001) but more predisposed to non-traditional risk factors than AMI-CO patients (3.7% against 1.8%; P = 0.026). Smoking is the only traditional risk factor frequent in the MINOCA population versus MI-CAD (P at 0.001). Depression, stress, drug addiction, DVT history and autoimmune disease history are more frequent in the MINOCA population versus MI-CAD (P <0.05) STEMI are more found in the MINOCA population versus MI-CAD (P = 0.000) In terms of prognosis, the MINOCA population had a better prognosis: less risk of recurrence than the MI-CAD population 6.7% versus 10.45% (P = 0.03) also less mortality 0% versus 4.6% (P = 0.007). Conclusion: The patients with MINOCA were more men, smokers, depressed, stressed, drug addicts with hypercoagulable states compared to patients with obstructive coronary artery disease (MI- CAD) however they had a better quality of life and a good prognosis.