Prevalence and Clinical Profile of Patients with Myocardial Infarction with Non-obstructive Coronary Arteries in Turkey (MINOCA-TR): A national multi-centre, observational study

OBJECTIVE: Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) is a relatively new term that is characterized by clinical evidence of MI with normal or near-normal coronary arteries on coronary angiography (QCA). To date, there have been no population-based studies on the prevalence of MINOCA in Turkey. The aim of this nationwide study was to document the prevalence and demographics of MINOCA in a Turkish population. METHODS: MINOCA-TR is national, multi-center, prospective, all-comer study that was conducted in 32 hospitals. All consecutive patients who were ≥18 years old, diagnosed with MI according to the Third Universal Definition of Myocardial Infarction, and had undergone QCA were included in the study. Patients with stable coronary artery disease, unstable angina pectoris, a history of revascularization, and type 4/5 MI were excluded. RESULTS: A total of 1793 patients who were diagnosed with MI and had undergone QCA were screened between March 2018 and October 2018, of whom 1626 (mean age: 61.5±12.5 years, 70.7% male) were enrolled from 32 centers. The prevalence of MINOCA was 6.7% (n=109) in the overall study population. Compared with non-MINOCA patients, those with MINOCA were younger, had a higher prevalence of the female gender, and had a history of flu. The percentages of current smokers, ST-segment elevated myocardial infarction patients, and those with a history of hypertension, diabetes mellitus, and hyperlipidemia were significantly lower in MINOCA patients (p<0.05, for all). Also, the median left ventricular ejection fraction as seen on echocardiography and the ratio of Killip Class I status at presentation was significantly higher in MINOCA patients than in non-MINOCA patients (p<0.001). Patients with MINOCA received a preload dose of P2Y12 antagonist before QCA less often than non-MINOCA patients (p<0.001). CONCLUSION: The prevalence of MINOCA in Turkey is 6.7% in patients who were admitted with MI. Also, as compared to non-MINOCA patients, the MINOCA patients were exposed to fewer traditional risk factors of coronary artery disease.