Myocardial infarction without coronary artery atherosclerosis ( MINOCA) — scientific interest or practical need?

Abstract

In recent years, much attention has been paid to the diagnosis and treatment of myocardial infarction (MI) without obstructive coronary artery atherosclerosis (MINOCA). According to statistics, the average prevalence of MINOCA is 6 — 8 % of all cases of MI. The diagnostic criteria for MINOCA are: presence of criteria for MI, absence of obstructive coronary artery disease according to data of coronary angiography (including angiographic stenosis < 50 %); no other cause of myocardial damage. According to the consensus of the American Heart Association (AHA) (2019), the diagnosis of MINOCA includes 3 stages. In the first stage, reanalysis of the clinical situation should be performed to rule out alternative diagnoses. In the second stage, it is necessary to evaluate the functional reserve of blood flow, to exclude non‑ischemic mechanisms of damage with the help of instrumental methods of research. The third stage is carried out in a specialized clinic, where the etiological factors of MI are verified.The article presents a clinical case of MI in a patient of 26 years of age. The diagnosis was confirmed by an increased level of troponin, changes in the electrocardiogram, echocardiographic examination and magnetic resonance imaging. With CA performed within 12 hours from the onset of the disease, hemodynamically significant coronary artery constrictions were not detected. During the laboratory examination, a significant increase in the level of homocysteine was found — 69 μmol/l (norm < 12.0 μmol/l). Given the weighted heredity, the emergence of MI at a young age, the absence of triggering factors (medications, stress, excessive physical activity, trauma, etc.) and diseases (diabetes, systemic connective tissue disease), an increased level of homocysteine, the role of thrombosis is highly probable. The patient is advised to consult a hematologist to identify hereditary thrombophilia as the cause of thrombosis (while taking antiplatelet/anticoagulant therapy performance of the tests and their interpretation are incorrect). It is recommended to take an angiotensin‑converting enzyme inhibitor, clopidogrel 75 mg/day, rivaroxaban 2.5 mg 2 times a day; β‑blocker, statins. Given the high level of homocysteine, the patient should follow a diet rich in folic acid‑rich foods.