Clinical and laboratory features of primary acute myocardial infarction in patients with non-obstructive atherosclerotic lesions of the coronary arteries.

Currently, the pathogenetic mechanisms of myocardial infarction (MI) in non-obstructive coronary artery disease (CA) are being actively studied, but such clinical situations still cause difficulties due to conflicting information about the clinical manifestations of myocardial ischemia, the dynamics of laboratory parameters, electrocardiographic and echocardiographic picture in this category of patients. Purpose. To study clinical and laboratory features ofprimary MI development and course in patients with non-obstructive CA lesions. Material and methods. The study included patients hospitalized with a diagnosis of “primary acute MI” in 2015-2016 : patients with acute MI and 100% acute occlusion of the only heart attack-responsible KA - obstructive atherosclerotic lesion of KA-and patients with acute MI and non-obstructive atherosclerotic lesion of KA, according to coronary angiography. Results. Surveyed 1,240 patients; the 1st group was 21.9%, 2nd group-7.7% of patients. The mean age of patients in groups 1 and 2 was 56.59±11.6 and 67.9±11.5 years, respectively (p<0.001). Among patients with non-obstructive atherosclerotic lesion of SC, the comorbid background was marked as burdened compared to patients with obstructive atherosclerotic lesion of SC: diabetes mellitus-20.8% vs. 7.4%, chronic kidney disease-25% vs. 11.8%, chronic obstructive pulmonary disease-25% vs. 11.8%. The most common symptom of myocardial ischemia in groups 1 and 2 was chest pain (89.7% vs. 54.2%, p<0.05). In 37.5% of patients of group 2 non-specific symptoms were revealed. ST segment elevation was recorded in 76.5 and 37.5% (p<0.01) patients, respectively. Non-specific electrocardiographic changes were registered in 33.3% of patients of group 2. In the analysis echocardiographically indicators of significant differences indicators in the groups were not observed. Analysis of cardiospecific enzymes showed consistent dynamics of the concentration of troponin I in the 1st and 2nd groups at admission - 0.13 ng/ml (95% CI 0,03 0,31-) against 0.20 ng/ml (95% CI 0,04 - 3,23, p=0,8); after 6 h -20,21 ng/ml (95% CI 8,25 - 45,25) against 1.8 ng/ml (95% CI 0.87 to - of 7.06, p<0.0001). The natural dynamics of the level of creatine kinase and its MB fraction were detected only in patients of the 1st group. Significant changes in the 2nd group is not marked. Elderly patients, mostly women, with a burdened General somatic history are subject to primary MI with non-obstructive atherosclerotic lesion of SC. In the clinical picture of myocardial ischemia, 54.2% ofpatients have chest pain, in other cases-shortness of breath and nonspecific symptoms. In 33.3% of patients on the ECG revealed nonspecific changes that complicate the diagnosis of THEM.