Effect of haemodialysis and residual renal function on serum levels of galectin-3, B-type natriuretic peptides and cardiac troponin T.

Abstract

Levels of plasma markers of myocardial fibrosis (galectin-3), stretch (B-type natriuretic peptide (BNP)) and injury (troponin T (TnT)) may be affected by haemodialysis and residual renal function (RRF) in addition to cardiac pathology. We aimed to determine the association of RRF, urine output and haemodialysis itself on clinically important cardiac biomarkers in haemodialysis patients. Adult haemodialysis patients underwent venesection pre- and post- haemodialysis followed by echocardiography and inter-dialytic urine collection to calculate RRF (mL/minute/1.73m2 ) and urine output (mL/day). Galectin-3, BNP-32, NT-ProBNP and high-sensitivity TnT were measured and levels compared across tertiles of echocardiographic parameters, RRF and urine output using the non-parametric test for trend across ordered groups. Twenty-three patients (17 male) with mean age 67.7±13.8 years and median (interquartile range, IQR) dialysis duration 13.6 (9.8-19.1) months participated. Galectin-3 was substantially lower following haemodialysis: 55ng/mL (47-70) versus 23ng/mL (19-27, p<0.001), but other biomarkers changed little. By increasing tertile of RRF, post-dialysis galectin-3 was 32.6ng/mL (23.7-36.6), 21.9ng/mL (19.0-23.2) and 19.0ng/mL (16.9-21.0, p=0.001) and NT-ProBNP was 10,192ng/L (2,303-21,504), 2,037ng/L (1,224-10,795) and 1,481ng/L (172-2,890, p=0.016). Changes were less marked with BNP-32 and hs-TnT. Results were similar for daily urine volume, but left ventricular ejection fraction, left ventricular mass index and E:A ratio were not associated with biomarker concentrations. Plasma concentration of galectin-3 is reduced by the haemodialysis procedure. Lower RRF and urine volume are strongly associated with higher levels of galectin-3 and NT-Pro-BNP. These associations are important to the clinical interpretation of these biomarker levels in haemodialysis patients.