Использование модифицированного гарвардского степ-теста в определении толерантности к физической нагрузке у пациентов с функционально единственным желудочком сердца после тотального кавопульмонального соединения

According to the literature, nearly one-third of patients with congenital heart diseases have signs of heart failure. Objective: to assess the possibility and results of using a modified Harvard step test (MHST) for the evaluation of exercise tolerance in children with a functional single ventricle. The investigation covered 110 healthy children aged 6 to 16 years and 29 patients aged 3 to 16 years with a functional single ventricle after total cavopulmonary connection with an extracardiac conduit a year after surgery and fenestration closure. MHST using a complete protocol was carried out in 44,8% of the patients. In the other examinees, the reason for stopping the test was premature muscle weakness and dyspnea. This could establish Functional Class (FC) II heart failure in 55,2% of the sick children. In the examinees, the MHST index (MHSTI) characterizing exercise tolerance ranged from 22,4 to 111. The median MHSTI scores significantly differed between the groups of patients with FC I and II heart failure (p=0,021). Exercise tolerance was lower in 17,2% of the patients with a functional single ventricle; in the others it was average and above average (41,5 and 41,3%, respectively), which was suggestive of good hemodynamic adaptation in patients after surgery. The findings prove the safety and efficiency of using the above test in the evaluation of exercise tolerance in children 3 years of age and older.