Myocardial markers are highly altered by higher rates of fluid removal during hemodialysis

Introduction

Although hemodialysis is lifesaving in patients with kidney failure extensive interdialytic weight gain (IDWG) between dialyses worsens the prognosis. We recently showed a strong correlation between IDWG and predialytic values of cardiac markers. The aim of the present study was to evaluate if the cardiac markers N-terminal pro-B-type natriuretic peptide (proBNP) and troponin T were influenced by IDWG and speed of fluid removal (ultrafiltration-rate).

Methods

Twenty hemodialysis patients performed in total 60 hemodialysis (three each). Predialytic values of proBNP and troponin T and changes from predialysis to 180 min hemodialysis (180–0 min) were compared with the IDWG calculated in percent of body weight. The ultrafiltration-rate was adjusted (UF-rate_adj) to IDWG: (100 × weight gain between dialysis [kg])/(estimated body dry weight [kg] × length of hemodialysis session [hours]).

Results

UF-rate_adj correlated (Spearman) with (1) predialytic values of IDWG (r = 0.983, p < 0.001), proBNP (r = 0.443, p < 0.001), and troponin T (r = 0.296, p = 0.025); and (2) differences in proBNP_180–0min (r = 0.572, p < 0.001) and troponin T_180–0min (r = 0.400, p = 0.002). UF-rates_adj above a breakpoint of 0.60 caused more release of proBNP_180–0min (p = 0.027). Remaining variables in multiple regression analysis with ProBNP_180–0min as dependent factor were predialytic proBNP (p < 0.001) and the ultrafiltration-rate (p < 0.001).

Conclusion

Higher UF-rate_adj during dialysis was correlated to increased levels of cardiac markers. Data support a UF-rate_adj lower than 0.6 to limit such increase. Further studies may confirm if limited fluid intake and a lower UF-rate_adj should be recommended to prevent cardiac injury during dialysis.