The level of NT-proBNP in ambulatory patients with chronic heart failure with preserved ejection fraction of the left ventricle

The prevalence of chronic heart failure (CHF) remains high. Echocardiography is a reliable method of diagnosing heart failure. Determination of brain natriuretic peptide allows to identify patients with the most probable diagnosis of heart failure, which requires further instrumental examination of patients. Aim. To study the level of the brain natriuretic peptide in patients with diastolic chronic heart failure with preserved left ventricular ejection fraction. Materials and methods. The study included 96 outpatients with diastolic chronic heart failure I-III functional class with a preserved left ventricular ejection fraction at the age of 65.06 +/- 1.15 years and 50 practically healthy people aged 39.90 +/- 1.64 years as a control group who underwent a preventive examination. The level of the N-terminal fragment of the medullary natriuretic peptide (NT-proBNP) in serum was determined using a test system (Vector-Best, Russia). Results. The concentration of NT-proBNP in patients with diastolic heart failure with a preserved left ventricular ejection fraction was 108.18 +/- 21.64 in the range from 0.0 to 1212.3 pg/ml compared to the control of 7.6 +/- 1.38 pg/ml, p<0.05. A positive correlation was found between the concentration of NT-proBNP and the area of the left atrium (r=0.35), left ventricular E/e '(r=0.6), and left ventricular end-systolic volume (r=0.48). The level of NT-proBNP had no correlation with the functional class of CHF (r=0,23), as well as with the stage of CHF (r=0,23). Conclusions. Thus, patients with diastolic CHF with a preserved ejection fraction in 67% of cases had a level of NT-proBNP in the blood less than the diagnostic threshold. The concentration of NT-proBNP in the serum positively correlates with increased pressure in the cavity of the left ventricle, the end-systolic volume in it and the area of the left atrium.