The significance of NT-proBNP decline in the evaluation of heart failure during maintenance hemodialysis

Objective To analyze the significance N-terminal pro-brain natriuretic peptide (NT-proBNP) decline in evaluation of heart failure during hemodialysis in patients with maintenance hemodialysis (MHD). Methods The level of NT-proBNP and ultrafiltration at 0 h, 1 h, 2 h, 3 h and end of hemodialysis were monitored in 92 patients with MHD. According to the conditions of blood pressure before dialysis, the patients were divided into hypotension group (48 cases) and stable blood pressure group (44 cases). NT-proBNP levels at various time points of dialysis were compared between the two groups. The rate of the rates of change of NT-proBNP changes at various timepoints were calculated, and correlation of NT-proBNP decline rates at various timepoints with ultrafiltration, was analyzed. Results (1) There was six patients in the hypotension group stopped at 2 hours of dialysis,and 42 ones performed dialysis for 3-4 hours. In the blood pressure stable group hemodialysis for all the patients lasted 4 hours. (2) There were differences in NT-proBNP levels between the two groups at 0, 1 h, 2 h, 3 h and end of dialysis (P<0.01). (3) The NT-proBNP decline rates at 1 h, 2 h, 3 h and 4 h of dialysis in the stable blood pressure group had positive correlation with the ultrafiltration volume (P<0.05). The NT-proBNP decrease rates at 1 h and 2 h of dialysis in the hypotension group was positively correlated with the ultrafiltration volume (P<0.01). The NT-proBNP decrease rates at 3 h and end of dialysis in the hypotension group had no correlation with the ultrafiltration volume (P>0.05). The lowest NT-proBNP decline rate in the hypotension group was -96.3%, the highest value was 78.6%, and the mean decrease rate of NT-proBNP was 38.5% when dialysis was intolerable in the hypotension group. Conclusions Hypotension patients with MHD have poor cardiac function and poor dialysis tolerance compared to stable blood pressure patients with MHD. NT-proBNP decline in patients with stable blood pressure and MHD is associated with reduced volume load, NT-proBNP decline rate in hypotension patients with MHD does not reflect the degree of volume load decrease.