Influence of Metoprolol Succinate on Regulatory and Adaptive Status of Patients With Chronic Heart Failure Functional Class I. Results of Not Comparative Study

Aim. To estimate metoprolol succinate effect on regulatory and adaptive status (RAS) of patients with сhronic heart failure (CHF) functional class (FC) I and arterial hypertension (HT) I-II stages. Material and methods. 51 patients with CHF FC I and HT I-II stage, (30 men and 21 women aged 52.6±1.4 yeas). Cardio-respiratory synchronism (CRS) test, 6-minute walking test, tread-mill burden test with registration of maximal oxygen consumption, 24-hour blood pressure monitoring, echocardiography and determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) blood level were performed initially and after 6 months of therapy with metoprolol succinate (dose 78.1±5.7 mg/day) in sustained-release presentation. Results. Metoprolol succinate therapy had no significant effect on RAS (there was no unidirectional dynamics of the basic CRS test parameters: a range of synchronization decreased significantly from 8.8±0.4 to 7.2±0.6 сardio-respiratory cycles per minute (in 18%; р<0.05), and duration of CRS development on the minimal boundary from 18.8±2.2 to 14.3±1.2 сardiocycles (in 24%; р<0,05); RAS index considerably did not change), myocardium structure, exercise tolerance and neuro-humoral activity. Metoprolol therapy only moderately improved left ventricle diastolic function. Conclusion. Metoprolol succinate therapy has no significant effect on RAS of patients with CHF FC I and HT I-II stages.