Percutaneous Arteriovenous Fistula Creation with the WavelinQ 4-French EndoAVF System: A Single-Center Retrospective Analysis of 30 Patients.

PURPOSE: To retrospectively assess the safety and efficacy of percutaneous arteriovenous fistula (pAVF) creation with the WavelinQ 4-F EndoAVF System. MATERIALS AND METHODS: From February 2018 to June 2020, 30 pAVFs were created in 30 consecutive patients (men; age, 55.3 years ± 13.6). Of the 30 patients, 21 (70%) were already on hemodialysis using a central venous catheter. The primary outcome measures were technical success, complications, and cannulation rate. The secondary outcome measures included the number of secondary procedures needed for cannulation, maintenance time to cannulation, and pAVF survival. RESULTS: Technical success was 100%. The adverse event rate was 6.7% (2/30), including a pseudoaneurysm of the brachial artery that developed immediately after sheath removal and an aneurysm of the anastomosis 17 days after the procedure, which was treated with a covered stent placed in the arterial side. The mean follow-up was 547 days ± 315.7 (range, 14-1,071 days). The cannulation rate was 86.7% (26/30). The mean time to cannulation was 61.3 days ± 32.5 (range, 15-135 days). The mean follow-up after cannulation was 566.2 days ± 252.7 (range, 35-1,041 days). Four pAVFs were thrombosed after cannulation, with 2 of them successfully declotted. Sixteen interventions were needed to achieve cannulation after the index procedure in 15 patients (overall, 0.53 procedures/patient). Seven maintenance endovascular interventions (following cannulation) were performed during the follow-up period in 6 patients (overall, 0.27 procedures/patient, 0.17 procedures/patient-years). For the pAVFs that were cannulated, patency was 96% at 1 year, and 82% at 2 and 3 years, according to the Kaplan-Meier survival analysis. CONCLUSIONS: This initial experience suggests that pAVF creation is safe and can be successfully performed with high maturation and long-term patency rates. Larger-scale prospective studies are needed to validate the results.

Altered Expression of Intestinal Tight Junction Proteins in Heart Failure Patients with Reduced or Preserved Ejection Fraction: A Pathogenetic Mechanism of Intestinal Hyperpermeability.

Although intestinal microbiota alterations (dysbiosis) have been described in heart failure (HF) patients, the possible mechanisms of intestinal barrier dysfunction leading to endotoxemia and systemic inflammation are not fully understood. In this study, we investigated the expression of the intestinal tight junction (TJ) proteins occludin and claudin-1 in patients with HF with reduced (HFrEF) or preserved ejection fraction (HFpEF) and their possible association with systemic endotoxemia and inflammation. Ten healthy controls and twenty-eight patients with HF (HFrEF (n = 14), HFpEF (n = 14)) underwent duodenal biopsy. Histological parameters were recorded, intraepithelial CD3+ T-cells and the expression of occludin and claudin-1 in enterocytes were examined using immunohistochemistry, circulating endotoxin concentrations were determined using ELISA, and concentrations of cytokines were determined using flow cytometry. Patients with HFrEF or HFpEF had significantly higher serum endotoxin concentrations (p < 0.001), a significantly decreased intestinal occludin and claudin-1 expression (in HfrEF p < 0.01 for occludin, p < 0.05 for claudin-1, in HfpEF p < 0.01 occludin and claudin-1), and significantly increased serum concentrations of IL-6, IL-8, and IL-10 (for IL-6 and IL-10, p < 0.05 for HFrEF and p < 0.001 for HFpEF; and for IL-8, p < 0.05 for both groups) compared to controls. Occludin and claudin-1 expression inversely correlated with systemic endotoxemia (p < 0.05 and p < 0.01, respectively). Heart failure, regardless of the type of ejection fraction, results in a significant decrease in enterocytic occludin and claudin-1 expression, which may represent an important cellular mechanism for the intestinal barrier dysfunction causing systemic endotoxemia and inflammatory response.

Altered Expression of Intestinal Tight Junctions in Patients with Chronic Kidney Disease: A Pathogenetic Mechanism of Intestinal Hyperpermeability.

BACKGROUND: Systemic inflammation in chronic kidney disease (CKD) is associated (as a cause or effect) with intestinal barrier dysfunction and increased gut permeability, with mechanisms not yet fully understood. This study investigated different parameters of the intestinal barrier in CKD patients, especially tight junction (TJ) proteins and their possible association with systemic endotoxemia and inflammation. METHODS: Thirty-three patients with stage I-IV CKD (n = 17) or end-stage kidney disease (ESKD) (n = 16) and 11 healthy controls underwent duodenal biopsy. Samples were examined histologically, the presence of CD3+ T-lymphocytes and the expression of occludin and claudin-1 in the intestinal epithelium was evaluated by means of immunohistochemistry, circulating endotoxin concentrations were determined by means of ELISA and the concentrations of the cytokines IL-1ß, IL-6, IL-8, IL-10 and TNF-α in serum were measured using flow cytometry. RESULTS: Patients with stage I-IV CKD or ESKD had significantly higher serum endotoxin, IL-6, IL-8 and IL-10 levels compared to controls. Intestinal occludin and claudin-1 were significantly decreased, and their expression was inversely correlated with systemic endotoxemia. Regarding occludin, a specific expression pattern was observed, with a gradually increasing loss of its expression from the crypt to the tip of the villi. CONCLUSION: The expression of occludin and claudin-1 in enterocytes is significantly reduced in patients with CKD, contributing to systemic endotoxemia and inflammatory responses in these patients.

Vascular access hands-on training for young nephrologists: The fellows' experience of the N-PATH project REVAC module.

Chronic kidney disease is a major public health problem, as population studies record a prevalence of 7.2% in individuals over 30 years and is expected to increase in the future. Many of them will end up undergoing hemodialysis treatment, and vascular access is not only an essential requirement for the technique, but also a determining factor in their prognosis; for all these reasons, every nephrologist should have both theoretical and practical knowledge of vascular access; however, the practical training is generally uneven and dependent on the hospital in which you train. It is within this context that the N-PATH (Nephrology Partnership for Advancing Technology in Healthcare) program was born with the objective of training 40 young European nephrologists in theoretical and practical aspects of Interventional Nephrology. To fulfill its mission, the 2-year program is composed of four modules of 6 months each including theoretical courses and hands-on training: Renal Expert in Molecular Pathology (REMAP), Renal Expert in Vascular Access (REVAC), Renal Expert in Medical Ultrasound (REMUS), and Renal Expert in Peritoneal Dialysis (REPED). By bringing together young nephrologists from all over Europe, the goal is also to create a strong network and promote Nephrology career at the European level. This publication highlights the experience of fellows who attended the REVAC hands-on training in Milan, focused on simulation and virtual reality for vascular access, and its impact on their nephrology training.

Drug-Coated Balloons for the Dysfunctional Vascular Access: An Evidence-Based Road Map to Treatment and the Existing Obstacles.

An underlying stenosis within the venous limb of a hemodialysis access circuit is the main etiology for graft and fistula dysfunction as well as other symptoms such as arm, breast, and neck swelling. Treatment options for both peripheral and central venous stenoses include plain old balloon angioplasty, angioplasty with drug-coated balloons, and stenting. This article discusses the current evidence for the use of drug-coated balloon angioplasty in this patient population.