Aim. To identify specific risk factors and features of the course of myocardial infarction (MI) in young patients.

Material and methods. The study design is based on a comparison of observation data for patients of different ages from the Russian RECORD-3 registry (n=2359) and the registry of acute coronary syndrome of the Kemerovo city in 2015 (n=1343). The clinical and anamnestic portrait was determined, the frequency of hospital complications and the “hard” endpoints were evaluated.

Results. Young patients with myocardial infarction (MI) according to RECORD-3 are more often male smokers (p=0.001) with a heredity in cardiovascular pathology (p=0.034), who have an uncomplicated STEMI upon admission to the hospital, and are sent for coronary angiography with stenting (p=0.001), without prescribing statins in the primary and secondary prevention (p=0.050 and p=0.016, respectively). There were no differences with other age groups by endpoints a year later; during the current hospitalization, young patients less often died (p=0.001) or had a relapse of MI (p=0.011). Young patients with MI from Kemerovo were also mostly male smokers (p=0.001), who more often had a history of chronic kidney disease, chronic heart failure, and lipid metabolism disorders (p=0.001), who admitted to the hospital with uncomplicated STEMI, actively undergoing thrombolytic therapy and endovascular diagnosis and treatment (p=0.001). However, it should be noted that these patients were less likely to receive aspirin (p=0.015), dual antiplatelet therapy (p=0.003), angiotensin converting enzyme (ACE) inhibitors (p=0.040) and statins (p=0.001). Moreover, in young patients with MI, deficiency of high density lipoproteins (p=0.005) was more often found in the absence of very high values of low density lipoproteins (p=0.001). Among the complications of inpatient treatment, it should be noted a tendency to bleeding (p=0.001). One year after referent MI a high proportion of repeated non-fatal MI (p=0.005) and deaths (p=0.001) were observed. A comparison of the registries showed that young patients from Kemerovo were more likely to have STEMI (p=0.032), they were more likely to have stenting (p=0.004), they were more often diagnosed with chronic renal and heart failure (p=0.001), and more often ACE inhibitors was prescribed (p=0.017), and MI during hospitalization was more often complicated by bleeding (p=0.003).

Conclusion. From 1.7 to 2.4% of all MI occurs in young patients. The most frequent version of the debut is STEMI. The leading factors of cardiovascular risk in such patients are the male gender, active smoking, a hereditary history of cardiovascular diseases, low cholesterol of high density lipoproteins with insufficient statins prevention. In young patients of the Kemerovo registry, chronic heart failure and chronic kidney disease were more often observed, and ACE inhibitors were prescribed, hospitalization was often accompanied by bleeding. In a young age differences in the frequency and structure of outcomes in one year after referent MI were not found when comparing registries.