Acute effects of conventional and extended hemodialysis and hemodiafiltration on high-sensitivity cardiac troponins

Abstract

Elevated concentrations of cardiac troponin T (cTnT; ±37 kDa) and I (cTnI; ±24 kDa), and the N-terminal fragment of the prohormone brain-type natriuretic peptide (NTproBNP; ±8.5 kDa) have been reported in end-stage renal disease patients and are associated with cardiovascular morbidity and mortality [1,2]. Also, cTnT, cTnI and NTproBNP correlate with glomerular filtration rate, suggesting a significant role of renal removal and consequences for the clinical interpretation of these cardiac markers [3]. The influence of hemodialysis (HD) on cardiac biomarkers itself remains contradictory. Previous studies have demonstrated intra-dialytic decreases [4] and increases in NTproBNP [5]. Also, significant reductions as well as increases in cTnT and cTnI concentrations have been reported following dialysis [5][6][7][8]. These differences can be attributed to the use of different dialysis modalities and membrane filters [5,8].Currently, most patients are treated with 4-h high-flux HD. However, it has been shown that uremic toxins were better removed when patients were treated with hemodiafiltration (HDF) and extended 8-h dialysis treatments resulted in more hemodynamic stability [9]. The aim of the present study was therefore to assess the acute effects of conventional and extended high-flux HD and HDF on cardiac biomarkers in the same population as previously described [9], especially focusing on high-sensitivity (hs-) cTnT and hs-cTnI results.Prevalent conventional HD patients were recruited receiving chronic conventional HD treatments, without residual urine production and acute illness, such as infection or cardiovascular events. All patients underwent one mid-week session in random order: 4-h HD (HD4), 8-h HD (HD8), 4-h online HDF (HDF4) and 8-h online HDF (HDF8) sessions; with a 2-week interval between the study sessions. Between the study sessions, these patients received conventional HD (HD4) treatments. All treatments were performed with the Fresenius 5008 Therapy System (Fresenius Medical Care). High-flux FX80 and FX800 dialysers (both Fresenius) were used for HD and HDF, respectively. Blood flow and dialysate flow were 300 and 600 mL/min, respectively. Substitution flow was 83.3 mL/min to achieve a total substitution volume of 15 L for HDF4 and 30 L for HDF8. Dialysate composition was 1.5 mmol/L calcium, 2 mmol/L potassium, 136-138 mmol/L sodium and 35-38 mmol/L bicarbonate and remain unchanged during the study period. This study (NL34908.068.10/MEC10-2-098) was approved by the Local Ethics Committee, and written informed consent was obtained from each patient.Blood was drawn from the inlet bloodlines in serum tubes, immediately before and after dialysis. Serum samples were aliquoted, stored at −80 °C and thawed prior to analysis. For HDF8, hs-cTnI and NTproBNP could not be measured in three patients due to a lack of

Variation of High-Sensitivity Troponin T Results in Patients Undergoing Continuous Renal Replacement Therapy

“…This likely reflects the longer duration of dialysis and possibly the greater convective clearance of larger molecular weight substances such as hs-cTnT (and/or their degradation products, which have been shown to cross-react with the hs-cTnT assay). 9 This is also consistent with the study by Cardinaels and colleagues 7 demonstrating greater reduction in serum levels of hs-cTnT with longer duration of hemodiafiltration.…”

“…6 Another study using high-sensitivity cTnT (hs-cTnT) demonstrated no reduction after conventional HD, but interestingly a significant reduction in serum levels after hemodiafiltration, particularly with a longer duration. 7 In a study of 10 chronic HD patients, we recently demonstrated that hs-cTnT falls by approximately 11% during and shortly after HD, before rising back to baseline levels 11 hours later. 8 The purpose of this study was to describe the influence of CRRT on hs-cTnT levels among patients admitted to the ICU with AKI.…”

High sensitivity Troponin-I levels in asymptomatic hemodialysis patients

“…The remaining studies that used high-flux HD reported median percentage reduction only up to 7.6%. This might be caused by the prescriptions of blood flow and dialysate flow rates in previous studies was lower than the present study [18,19]. The clearance by dialysis would be the explanation of this reduction.…”

“…The effect of HD on hsTnI levels are unestablished, reporting either increasing [17], unchanged [14,18] or decreasing of post-dialysis hsTnI levels (Table 3) [19,24]. The present study demonstrated that dialysis process affected the levels of hsTnI.…”

“…This might not represent the majority of HD patients currently undergoing high-flux HD which includes either HD or online hemodiafiltration (HDF) using high-flux dialyzer. Three studies in high-flux HD patients included quite a small number of patients [14,18,19] while the other two studies did not focus on the subgroup of patients with heightened post-dialysis hsTnI from possible intradialytic myocardial hypoperfusion [15,16]. On the contrary, modern HD modalities might remove TnI molecule and reduce post-dialysis hsTnI levels.…”