Comparative characteristics of patients with acute coronary syndrome without ST segment elevation depending on extent of coronary artery stenosis (Record-3 data)

The aim of the study was to create a patient portrait, to evaluate prognosis, and establish the principles of therapy in patients with acute coronary syndrome without ST elevation with non-obstructive coronary atherosclerosis in comparison with the obstructive coronary atherosclerosis group.Material and Methods. Data come from the acute coronary syndrome register REСORD-3 that was implemented in the Emergency Cardiology Department of Cardiology Research Institute, Tomsk National Research Medical Centre, along with 45 other centers in Russia. Patients with myocardial infarction without ST segment elevation who were exposed to coronary angiography were separated into two independent groups based on whether they had MINОСА or not: 148 persons with non-obstructive coronary atherosclerosis and 537 persons with obstructive coronary atherosclerosis.Results. Non-obstructive coronary atherosclerosis group, compared to obstructive coronary atherosclerosis, comprised 75 women (50.7%) compared to 177 men (32.9%). Hypertension was detected less often in this group: 120 (81.1%) versus 475 (88.5%). The rates of diabetes mellitus were 16 (10.8%) versus 115 (21.4%) and the rates of smoking were 162 patients (30.2%) versus 32 (21.6%), respectively, in patients with and without non-obstructive coronary atherosclerosis. Non-obstructive coronary atherosclerosis group had significantly lower rate of individuals with diagnostic increase in cardiospecific enzymes. This may be indicative of non-prolonged myocardial ischemia that, in some cases, does not lead to necrosis. The final diagnosis of non-ST segment elevation myocardial infarction was significantly less confirmed in patients with non-obstructive coronary atherosclerosis (14.8 vs. 45.3%). However, in this group, the “other cardiac cause of hospitalization” was more frequent (29.7 vs. 2.2% of cases), which explains the need to continue the diagnostic search to exclude all possible causes of the chest pain. The variety of final diagnoses in patients with acute coronary syndrome with non-obstructive coronary atherosclerosis and “clean” coronary arteries should encourage a thorough analysis of the pathogenesis in each of these patients.Conclusion. A typical acute coronary syndrome patient with non-obstructive coronary atherosclerosis without ST segment elevation was represented by a 59 (53:65)-year-old woman with traditional risk factors for coronary heart disease, but the incidence of each of these factors was less than in the obstructive coronary atherosclerosis group. Final diagnosis of non-ST segment elevation myocardial infarction was confirmed significantly less often in patients with non-obstructive coronary atherosclerosis. The mortality rates did not differ between groups and were minimal. Acute coronary syndrome patients with non-obstructive coronary atherosclerosis without ST segment elevation were less likely to receive ticagrelor and statins in hospital, but they were administered more often with fondaparinux. Patients with non-obstructive coronary atherosclerosis at discharge were less likely to be recommended to take antiplatelet agents, statins, and nitrates.