One-hour Diagnostic Algorithm for NSTEMI

After enrollment in the study, patients will undergo the following procedures: 1. Physical examination (at baseline) and monitoring of vital signs (blood pressure, heart rate, breathing rate) at hours 1, 2, and 3 after admission to hospital. 2. Registration of 12-lead electrocardiogram (ECG) (at baseline, after 24 hours, and at the day of discharge). 3. At baseline (at the time of admission to hospital), venous blood will be obtained to perform blood tests for determination of troponin I, FABP, and CPK-MB levels. At the same time, venous blood will be sampled for routine clinical laboratory blood tests. At hours 1, 2, and 3 after admission to hospital, venous blood will be sampled for assessment of the troponin I and FABP levels. 4. Echocardiography will be performed 24 hours after admission (LVEDV, LVESV, and EF). At day 3, standard echocardiography will be performed.