PECULIARITIES OF EXERCISE TOLERANCE IN THE POST-INFARCTION PERIOD DEPENDING ON THE PRESENCE OF DECOMPENSATED HEART FAILURE

The aim of the study was to evaluate the functional capacity and expediency of using a six- minute walk (SMW) test in patients with decompensated heart failure (HF) in the early and late post-infarction period against the background of indicators of natriuretic propeptide type B. Materials and methods. There were exam- ined 160 patients with acute myocardial infarction. De- pending on the development of decompensated HF in the early and late post-infarction period, the patients have been divided into two subgroups. The major criterion for inclusion of patients to the study was transferred not earlier than 28 days after the beginning of Q-QS and non- Q myocardial infarction. Clinical diagnosis has been made in accordance with the recommendations of the European Society of Cardiologists. The studied groups were homogeneous according to age, sex, severity of the disease, duration of post infarction period, presence of clinical manifestations of decompensation. SMW test, individual susceptibility to Borg scale, CG in 12 standard leads was evaluated for the purpose of fixing hemody- namic destabilization, immuno-enzymatic determination of NT-proBNP level were performed to all patients. Results of the research and their discussion. During the study of clinical and electrocardiological signs of functional capacity, such as depression of the ST seg- ment, angina pectoris, dyspnea, central and peripheral nervous systems symptoms (dizziness, cyanosis/pallor) and a significant deterioration in the status of patients with Q-QS and non-Q MI complications with complicat- ed decompensated HF, were detected. Because of analyz- ing six-minute walk test, it was found that the presence of decompensated HF significantly degrades the perfor- mance of it. The deterioration has also been found of individual perception of loading in patients with decom- pensation of HF in the early and late post infarction peri- od. In patients with signs of decompensation in the post infarction period, there were probably higher levels of NT-proBNP in serum and amounted to (850.54 ± 20.51) pg/ml (p≤0.05) compared with the first group (428.5 ± 6, 81) pg/ml (p≤0.05). Thus, the most important for the clinical and prognostic estimation of the post infarction period complicated by decompensated HF is the response of the patient's organism to metered physical activity and the level of NT-proBNP. Conclusions. During the study, it has been found out that an inadequate response to metered physical activity, a high level of NT-proBNP may be useful not only for early diagnosis and prediction of the occurrence of decompensated heart failure in the early and late post infarction period, but also for the decision on optimal further dispensary treatment of such contingent of the patients and decision on discharge after hospitalization. Increasing the tolerance to physical activity can help prevent the formation of decompensation of HF in the post-infarction period.