Peculiarities of chronic heart failure formation in patients with persistent atrial fi brillation depending on the renal dysfunction phenotype

Aim. To study the features of chronic heart failure (CHF) formation in patients with persistent atrial fibrillation (AF) depending on the phenotype of renal dysfunction. Material and Methods . The study included 60 patients with persistent AF and CHF. To diagnose CHF, echocardiography study was performed and the concentrations of NT-pRoBNP and sST2 in the blood serum were determined. Renal filtration function was assessed by glomerular filtration rate (GFR) calculated based on creatinine and cystatin C. Plasma NGAL concentration was determined to assess tubular dysfunction. Three phenotypes of renal damage were identified. Group 1 included 14 individuals (23.3%) with isolated tubular dysfunction assessed by NGAL; group 2 included 14 patients (23.3%) with isolated glomerular dysfunction assessed by GFR (CKD-EPIcys); group 3 comprised 32 patients (53.3%) with a combination of tubular and glomerular dysfunction. Results . The GFR value (CKD-EPIcre) below 60 mL/min/1.73 m2 was found in 36.7% of patients from groups 2 and 3. The concentration of cystatin C significantly diff ered between groups and was the highest in group 3. The value of GFR (CKDEPIcys) below 60 mL/min/1.73 m2 was detected in 76.7% of patients from all groups. The value of GFR (CKD-EPIcys) significantly diff ered between groups and was the lowest in group 3. When comparing serum creatinine and cystatin C in group 1, eight patients (57.1%) showed latent glomerular dysfunction, which manifested only in the concentration of cystatin C. A relationship was found between the level of DBP and NGAL (r = 0.44; p < 0.05). The correlations were identified between the parameters of left ventricular (LV) diastolic function and indicators of filtration function and tubular apparatus of the kidneys, namely: between E/e’ and NGAL concentration (r = 0.31; p < 0.05); between E/e’ and cystatin C concentration (r = 0,30; p < 0.05); between E/A and NGAL concentration (r = –0.36; p < 0.05); and between septal e’ and cystatin C concentration (r = –0.30; p < 0.05). Relationships were found between the concentrations of NGAL and sST2 (r = 0.44; p < 0.05) and between the concentrations of cystatin C and TIMP-1 (r = 0.39; p < 0.05). Conclusion . The use of blood cystatin C to assess kidney filtration function allowed to detect latent glomerular dysfunction in 57.1% of patients with heart failure and persistent AF, which could not be determined by GFR (CKD-EPIcre). Patients with persistent AF developed CHF with preserved LV EF regardless of the phenotype of renal dysfunction. The severities of glomerular filtration and kidney tubular apparatus abnormalities correlated with the severity of diastolic dysfunction. Unlike clinical indicators and blood concentration of NT-proBNP, sST2 levels allowed to detect the diff erences in heart failure severity in patients with persistent AF depending on the phenotype of renal dysfunction: the lowest severity was observed in the presence of glomerular dysfunction; the highest severity was found in the presence of combined dysfunction. Glomerular dysfunction in patients with CHF and persistent AF was associated with the impaired collagen formation and TIMP-1 activation.