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BACKGROUND: Brain natriuretic peptide (BNP), N-terminal-proBNP (NT-proBNP), and high sensitive cardiac troponin T (TnT) are markers that are elevated in chronic kidney disease and correlate with increased risk of mortality. Data are conflicting on the effect of biomarker levels by hemodialysis (HD).Our aim was to clarify to what extent HD with low-flux (LF) versus high-flux (HF) membranes affects the plasma levels of BNP, NT-proBNP, and TnT.

METHODS AND MATERIALS: 31 HD patients were included in a crossover design, randomized to start dialysis with a LF-HD or HF-HD dialyzer. Each patient was his/her own control. The dialyses included in the study were the first treatments of two consecutive weeks with each mode of dialysis. Patients normally on hemodiafiltration (HDF) also performed a HDF the third week. Values after HD were corrected for extent of ultrafiltration.

RESULTS: During LF-HD the biomarkers NT-proBNP and TnT increased (15 versus 6%, P ≤ .001) while there was a slight decrease in BNP (P<.05). During HF-HD the NT-proBNP, BNP and TnT levels decreased (P ≤ .01 for all). During HDF all three markers decreased (P<.01 for all). The rise in TnT during LF-HD correlated with dialysis vintage (months on HD, r = .407, P = .026), Kt/V-urea (r = .383, P = .037), HD time in hours/treatment (r = .447, P = .013) and inversely with residual urinary output (r = -.495, P = .005). The baseline levels of BNP and NT-proBNP correlated with blood pressure.

CONCLUSIONS: Cardiac biomarkers increase slightly during LF-HD. A HF-HD eliminates the biomarkers and can mask increases caused by, e.g., myocardial infarction.

Background: High interdialytic weight gain (IDWG) and ultrafiltration rate have been associated with increased mortality in patients undergoing haemodialysis. Cardiac biomarkers reflecting strain, including N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (TnT), are known to increase during haemodialysis sessions. Previous studies suggest that these intradialytic increases may be related to ultrafiltration rate, with a proposed threshold of 0.6 IDWG per hour. This study therefore aimed to prospectively evaluate whether reducing ultrafiltration rate attenuates the haemodialysis-associated increase in these cardiac biomarkers.

Method: In this multicentre, prospective study prevalent haemodialysis patients with a relative IDWG > 2.5% of body weight and ultrafiltration rate ≥ 0.72 IDWG per hour underwent one standard and one prolonged haemodialysis session with a ≥ 20% reduction in ultrafiltration rate, targeting an ultrafiltration rate ≤ 0.6 IDWG per hour. NT-proBNP and TnT were analysed directly before dialysis, at 180 minutes, and at the end of each haemodialysis session.

Results: Of 238 screened patients, 65 met the inclusion criteria and none of the exclusion criteria. Of these, 56 were enrolled and 41 included in the final analysis, meeting the pre-specified sample size required to detect a clinically relevant difference. NT-proBNP and TnT increased significantly during both dialysis sessions (p < 0.001). However, no difference was observed in ∆NT-proBNP (p = 0.967) or ∆TnT (p = 0.823) between treatments with different ultrafiltration rates. Achieving an ultrafiltration rate ≤ 0.6 IDWG per hour required a mean treatment duration of 423 ± 139 minutes (min 246, max 775). Among the 12 patients (29.3%) who achieved the targeted ultrafiltration rate of ≤0.6 IDWG per hour, changes in NT-proBNP (p = 0.062) and TnT (p = 0.114) did not differ significantly between sessions with different ultrafiltration rates.

Conclusions: In stable, prevalent haemodialysis patients who tolerate their ordinary treatment, reducing the ultrafiltration rate by at least 20% did not attenuate the increase in NT-proBNP and TnT during a single haemodialysis session. In these patients, achieving an ultrafiltration rate ≤ 0.6 IDWG/h generally required treatment durations that are not feasible in routine in-centre haemodialysis.

Background: An arteriovenous fistula (AVF) is the first choice when considering access for haemodialysis (HD).When a forearm AVF fails an upper arm AVF is a frequent subsequent dialysis access option. The latter may causecardiac strain. NT-pro-B-type natriuretic peptide (NT-NT-proBNP) is a marker used to estimate volume overload andcardiac strain.This case report shows the benefit of using longitudinal individual follow-up of pre-dialysis NT-proBNP in clinicalpractice to detect changes in cardiac condition that may be due to high-output AVF.

Case presentation: An 18 years old patient performed HD via an upper arm AVF before he was admitted to ourunit. NT-proBNP was above the upper detection level of 70,000 ng/L. Echocardiography revealed a left-ventricularcardiac insufficiency. Interdialytic weight gain (IDWG) was above 5%. He was instructed to lower fluid intake andIDWG towards 2%. Four months later NT-proBNP surpassed 70,000 ng/L again. Flow in the brachial artery was at3034 ml/min. Reconstructive surgery of the AVF did not reduce flow and NT-proBNP in the long run. Clinically, heworsened to NYHA class III-IV. It was decided to close the upper arm AVF and to replace it with a lower arm AVFleading to a reduced artery flow of 1344 mL/min. The clinical condition successively recovered and NT-proBNPdecreased to 7000 ng/L.

Conclusions: Pre-dialysis NT-proBNP should be considered as a suitable routine marker for cardiac strain such ascaused by high-output AVF besides variables such as IDWG. Brachial artery flow besides AVF flow measurement ishelpful.

Background: Haemodialysis access patterns differ internationally. This can not only be explained by differences in patient cohorts. What is considered the right access for the right patient is debated and it is unclear which patient-related factors affect the choice of access. The aim of the study was to investigate how patient-specific factors as body size and comorbidities influenced the choice of haemodialysis access in a real-life setting.

Methods: Retrospective cohort study including all patients receiving a haemodialysis access in Sweden between 2013 and 2022. Data from the Swedish Renal Registry (SNR) and the National Patient Register (NPR) was used. Data regarding age, sex, cause of kidney failure, previous kidney replacement therapy, height and weight (after dialysis), were collected from SNR. Data on comorbidities were extracted both from SNR and the NPR. AV-accesses were grouped into four categories depending on location of artery. Changes in arteriovenous access creation over time and patient-related factors affecting the choice of first access were analysed.

Results: Of 10,170 patients, 9706 with 17,709 accesses were included. The creation of upper-arm fistulas (p = 0.042) and arteriovenous grafts (p = 0.007) increased. Small body size, female sex, diabetes mellitus, vintage, previous haemodialysis treatment (all p < 0.001), age (p = 0.002) and peripheral arterial disease (p = 0.031) led to more central venous catheters. Small body size, female sex, peripheral arterial disease, vintage, previous haemodialysis treatment (all p < 0.001) and diabetes mellitus (p = 0.023) decreased the probability for selecting a forearm fistula. Upper-arm fistulas were preferred over arteriovenous grafts for those with small body size (p < 0.001 for body surface area), female sex (p = 0.003) and previous haemodialysis (p < 0.001).

Conclusions: The use of upper-arm fistulas and arteriovenous grafts is increasing, while forearm arteriovenous fistulas remain the primary access modality. Patient-related factors influencing the choice of access seemed to be related to vessel size and quality, rather than age and cardiovascular comorbidities.

Rationale & Objective: There is increasing evidence that arteriovenous fistulas (AVFs) might alter cardiac function. Upper arm AVFs are associated with higher access flow, and their use is increasing. It has been hypothesized that the creation of upper arm AVFs would lead to a higher incidence of heart failure compared with forearm AVFs.

Study Design: Retrospective cohort study.

Setting & Participants: All patients who received a hemodialysis access between 2013 and 2022 in Sweden. Patients with prevalent heart failure or previous hemodialysis were excluded.

Exposure or Predictor: Type of hemodialysis access and access flow.

Outcome: New-onset heart failure.

Analytical Approach: Cox proportional hazards regression for type of access and restricted cubic splines for access flow. Comorbid conditions were included as covariates in both models.

Results: In total, 10,170 patients were included. Of those, 6,579 patients with a total of 11,238 accesses remained after excluding patients with prevalent heart failure or prevalent hemodialysis. The risk of new-onset heart failure was comparable between forearm and upper arm AVF (P = 0.57). Access flow was highest in upper arm AVF (P < 0.001), but there was a substantial overlap. The risk of heart failure development depending on access flow was nonlinear (P < 0.001) with increased risk in patients with lowest as well as the highest flow.

Limitations: Reliance on International Classification of Diseases (ICD)-10 codes is a limitation because of potential underascertainment and misclassification. The findings may not be generalizable to settings where upper arm AVF are used more liberally than in Sweden.

Conclusions: Upper arm AVFs were not associated with the development of heart failure. Comorbid conditions such as ischemic heart disease, heart valve disease, and diabetes as well as age were more important factors for the development of heart failure than access type. The association between access flow and new-onset heart failure is U-shaped.