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This commentary uses the negative results of the PAVE (Paclitaxel-coated Balloons and Angioplasty of Arteriovenous Fistulas) study to (i) discuss the role of drug-coated balloons in the armamentarium of therapies for dialysis vascular access stenosis and (ii) suggest a more patient centered, individualized, and precision medicine-based approach for the future care of patients with dialysis vascular access dysfunction., (Copyright © 2021 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Endovascular salvage plays an important role in dialysis access care. Angioplasty using standard high- and ultrahigh-pressure balloon is the mainstay of therapy, while the use of cutting balloons and balloons designed to deliver pharmacologically active agents to the site of recurrent stenosis is demonstrating improved performance for specific targets that have to be further defined. Stents and stent grafts are additional tools for use at access segments predisposed for inward remodeling such as the cephalic arch or basilic swing point. The juxta-anastomotic segment has particular relevance in maturation of autogenous accesses as well as maintenance of access flow volume. Depending on the location of the access in the forearm or upper arm, and which artery is feeding into the access vein, any type of balloon angioplasty and stent or stent graft placement may be used to establish and maintain patency. Successful management of dialysis access options relies on preservation of venous real estate during the chronic kidney disease phase of kidney disease as well as on knowledgeable evaluation of arm veins and the access by physical examination, bed side ultrasound, and angiographic studies., (Copyright © 2020 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: To present final, 2-year results of a randomized trial comparing paclitaxel-coated vs uncoated balloon angioplasty following vessel preparation with ultra-high-pressure percutaneous transluminal angioplasty (PTA) in hemodialysis arteriovenous fistulae (AVFs)., Materials and Methods: Twenty-three sites enrolled 285 subjects with dysfunctional AVFs located in the arm. Before 1:1 randomization, successful vessel preparation was achieved (full waist effacement, < 30% residual stenosis). Follow-up was clinically driven except for a 6-month office visit., Results: Ninety-six of 141 subjects in the drug-coated balloon (DCB) arm and 111 of 144 in the control arm completed the study. Target lesion primary patency (TLPP) rates for the DCB and control groups were 58% ± 4 vs 46% ± 4 (P = .02) at 9 months, 44% ± 5 vs 36% ± 4 (P = .04) at 12 months, 34% ± 5 vs 28% ± 4 (P = .06) at 18 months, and 27% ± 4 vs 24% ± 4 (P = .09) at 24 months, respectively. Mean time to TLPP event for subjects with an event was longer for DCBs (322 vs 207 d; P < .0001). Fewer interventions were needed to maintain target lesion patency in the DCB group at 9 months (P = .02) but not at 12 (P = .08), 18 (P = .13), or 24 months (P = .19). The noninferiority safety target was met at all intervals (P < .01). Mortality did not differ between groups (P = .27). Post hoc analyses showed equivalent DCB effect in all subgroups., Conclusions: Two-year results demonstrate long-term safety and variable efficacy of DCB angioplasty in AVFs., (Copyright © 2019 SIR. Published by Elsevier Inc. All rights reserved.)

Children with chronic illness often require prolonged or repeated venous access. They remain at high risk for venous catheter-related complications (high-risk patients), which largely derive from elective decisions during catheter insertion and continuing care. These complications result in progressive loss of the venous capital (patent and compliant venous pathways) necessary for delivery of life-preserving therapies. A nonstandardized, episodic, isolated approach to venous care in these high-need, high-cost patients is too often the norm, imposing a disproportionate burden on affected persons and escalating costs. This state-of-the-art review identifies known failure points in the current systems of venous care, details the elements of an individualized plan of care, and emphasizes a patient-centered, multidisciplinary, collaborative, and evidence-based approach to care in these vulnerable populations. These guidelines are intended to enable every practitioner in every practice to deliver better care and better outcomes to these patients through awareness of critical issues, anticipatory attention to meaningful components of care, and appropriate consultation or referral when necessary., (© 2019 American Society for Parenteral and Enteral Nutrition.)

Background: Restenosis remains a problem in hemodialysis access interventions. Paclitaxel-coated balloons have shown promise in reducing access-related restenosis in small trials. The primary hypotheses for our multicenter trial were superior effectiveness at 180 days and noninferior safety at 30 days of a drug-coated balloon compared with conventional angioplasty for treatment of dysfunctional arteriovenous fistulas., Design, Setting, Participants, & Measurements: This randomized trial enrolled 285 patients with dysfunctional arteriovenous fistulas at 23 centers. Grafts, central venous stenoses, thrombosed fistulas, and immature fistulas were excluded. All patients received angioplasty of the lesion responsible for access dysfunction. After successful angioplasty (≤30% residual stenosis), lesions were treated with either a paclitaxel-coated balloon or an uncoated control balloon of similar design to the drug-coated balloon. Access function during follow-up was determined per centers' usual protocols; reintervention was clinically driven. The primary efficacy outcome assessment was done at 6 months, and the safety assessment was done within 30 days of the procedure. Prespecified secondary end points included assessment of postintervention target lesion primary patency and access circuit primary patency at 6 months., Results: The 180-day end point was not met with target lesion primary patency (71%±4% for the drug-coated balloon and 63%±4% for control; P =0.06), representing a difference of 8%±6% (95% confidence interval, -3% to 20%). Access circuit primary patency did not differ between groups. Interventions to maintain target lesion patency were fewer for the drug-coated balloon at 6 months (0.31 versus 0.44 per patient; P =0.03). The primary safety noninferiority end point was met and did not differ between groups ( P =0.002)., Conclusions: Paclitaxel-coated balloon-assisted angioplasty did not meet the primary effectiveness end point at 180 days compared with conventional angioplasty. Both arms showed equivalent safety (ClinicalTrials.gov number NCT02440022)., (Copyright © 2018 by the American Society of Nephrology.)

Purpose: To present final, 2-year data from randomized comparison of an expanded polytetrafluoroethylene stent graft (SG) and percutaneous transluminal angioplasty (PTA) for treatment of arteriovenous graft (AVG) anastomotic stenoses., Materials and Methods: A 28-site, prospective, controlled US study enrolled 270 patients with malfunctioning AVG anastomotic stenoses of ≥ 50%; 138 patients underwent SG placement, and 132 underwent PTA alone. Follow-up imaging and intervention were event-driven., Results: The study was completed by 191 patients (97 SG, 94 PTA). Five patients were lost to follow-up or withdrew; 74 patients died during the study (38 SG, 36 PTA). At 12 months, treatment area primary patency (TAPP) was SG 47.6% versus PTA 24.8% (P < .001), access circuit primary patency (ACPP) was SG 24% versus PTA 11% (P = .007), and index of patency function (IPF) was SG 5.2 months/intervention ± 4.1 versus PTA 4.4 months/intervention ± 3.5 (P = .009). At 24 months, TAPP was SG 26.9% versus PTA 13.5% (P < .001), ACPP was SG 9.5% versus PTA 5.5% (P = .01), and IPF was SG 7.1 months/intervention ± 7.0 versus PTA 5.3 months/intervention ± 5.2; estimated number of reinterventions before graft abandonment was 3.4 for SG patients versus 4.3 for PTA patients. There were no significant differences in adverse events (P > .05) except for restenosis requiring reintervention rates of 82.6% in PTA patients versus 63.0% in SG patients (P < .001)., Conclusions: At 2 years, SG use provided a sustained, greater than 2-fold advantage over PTA in treatment area and overall access patency. Time to subsequent intervention was longer in the SG group., (Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.)

Cardiovascular implantable electronic devices (CIEDs) are frequently utilized in hemodialysis patients. CIED leads are typically implanted via the subclavian vein resulting in stenosis and venous hypertension. We studied 1235 chronic hemodialysis patients under the care of our nephrology practice. For each, we determined the presence of a CIED, indication for implantable cardioverter-defibrillator (ICD), and type of hemodialysis access. Records were reviewed to identify all interventions performed on the access circuit and the central veins specifically. A CIED was present in 129 patients (10.5%), including ICDs in 75 (6.1%) and pacemakers in 54 (4.4%). The access circuit intervention rate was 1.48/access year (AY) and was similar when a CIED was ipsilateral (1.53/AY) or contralateral (1.44/AY) to arteriovenous access (p = 0.477). The rate of central venous interventions was greater in the ipsilateral (0.59/AY) versus contralateral group (0.28/AY), (p < 0.001). Fifty-four of 59 patients with ipsilateral access and CIED required <2 interventions per AY, but six failed angioplasty and required access ligation. None had superior vena cava stenosis requiring intervention. We conclude that there is a high prevalence of CIEDs in our HD patients. Ipsilateral CIED and arteriovenous access results in higher central venous intervention rates compared with contralateral cases; overall access circuit intervention rates are similar., (© 2014 Wiley Periodicals, Inc.)

Cardiovascular implantable electronic devices (CIEDs) are frequently utilized for management of cardiac dysrhythmias in patients with chronic kidney disease or end-stage renal disease receiving hemodialysis. The survival benefit from use of implantable cardioverter defibrillators in patients with CKD or ESRD is not as clear as in the general population, particularly when used for primary prevention of sudden cardiac death. Transvenous CIED leads are associated with central vein stenosis resulting in significant adverse consequences for existing or future arteriovenous access. Venous hypertension from CIED lead-related central vein stenosis is a challenging clinical problem and may require repeated percutaneous interventions, replacement of the CIED, or creation of alternative arteriovenous access. Infections associated with transvenous CIED leads are more frequent and associated with worse outcomes in patients with renal disease. Epicardial CIED leads or other nontransvenous devices may reduce complications of both central venous stenosis and endovascular infection in these vulnerable patients. Consensus recommendations are offered for avoidance and management of complications arising from the use of CIEDs and arteriovenous hemodialysis access., (© 2012 Wiley Periodicals, Inc.)

A high-quality autogenous arteriovenous fistula provides the optimal access for hemodialysis. Following initial surgical construction of a fistula, the maturation process is driven by hemodynamic, cellular, and humoral factors that must result in increased blood flow, vessel dilation, and thickening of the vessel wall before the fistula can be successfully used for dialysis needle access. Different demands are placed on each fistula depending on the individual patient's hemodialysis requirements, which must be clearly understood to properly assess and treat the immature fistula. When spontaneous maturation fails to achieve a functional fistula, additional surgical or minimally invasive interventional procedures may be necessary to enhance the maturation process. Various techniques have been reported to achieve successful fistula maturation. The purpose of this article is to review the concepts of fistula maturation and the interventions that may be performed in cases where there is failure to mature spontaneously.

Purpose: Symptomatic central vein stenosis commonly occurs when cardiac rhythm management device (CRMD) leads are placed via the subclavian vein ipsilateral to arteriovenous (AV) hemodialysis (HD) access. The purposes of this study were to determine the outcomes, complications, and patency following stenting of CRMD lead-associated central vein stenosis or occlusion, and to determine the effect of stents on CRMD function., Methods: Fourteen HD patients with AV access and an ipsilateral CRMD were treated with stents for symptomatic central vein stenosis or occlusion following inadequate response to angioplasty from January 2005 to December 2009. Subsequent access interventions, complications, and outcomes were reviewed retrospectively. Cardiology records were examined to assess CRMD function., Results: Treatment of stenosis or occlusion with angioplasty and stenting resulted in 100% procedural success and no complications. At 6 and 12 months, respectively, primary patency rates were 45.5% and 9.0%; primary-assisted patency rates were 90.9% and 80.0%; secondary patency rates were 100% and 90.0%. There were 42 repeat interventions performed in 12 patients; five received additional stents. The mean number of subsequent interventions was 3.2 per patient (2.1 per patient-year). All CRMD testing demonstrated normal function with no device or lead failure. Seven of the 14 subjects died resulting in a 35.3% annual mortality rate. No deaths were attributable to dysrhythmia or CRMD failure and no patient required CRMD removal or exchange., Conclusions: Placement of stents for CRMD lead-associated stenosis or occlusion yields high success and low complication rates with no effect on CRMD function. Patency rates are similar to those reported in other series of central venous stents.

The field of interventional nephrology is rapidly developing as an important new area of nephrology practice that holds great promise for improved patient care, outcomes, and cost control. This development is contingent on nephrologists acquiring the necessary knowledge and skills through suitable training and experience, and obtaining hospital privileges to perform these interventions. As more training programs are created, and credentialing criteria are established and accepted, it will become more practical for nephrologists to become interventionists. Reimbursement for interventional procedures can be complicated and confusing, with special problems applicable to a nephrology practice involved in the overall care of end-stage renal disease (ESRD) patients. It is essential to become familiar with applicable procedure codes, global periods, and code modifiers to correctly describe these procedures and receive correct reimbursement. Nephrologists work together with vascular access surgeons and interventional radiologists to provide care for dialysis patients. The role of each specialist in the management of vascular access depends on his or her level of interest, knowledge, and technical skill. These roles may vary considerably from one practice to another. There is potential for this area to become highly contentious, especially if one specialist feels threatened by the activities of another. Optimal patient care will be achieved only if all involved physicians take a serious intellectual interest in vascular access, develop superior clinical skills, and maintain cooperative, collegial, relationships., (Copyright 2002, Elsevier Science.)

Tunneled dialysis catheters (TDC) are extensively used for long-term venous hemodialysis access and their use is frequently associated with infectious complications. Catheter-related bacteremia (CRB) is the most common and important infection associated with TDC use and may be caused by a wide variety of Gram-positive or Gram-negative organisms. Prevention of CRB can be difficult despite use of rigorous infection-control techniques for catheter insertion and access. A number of antibacterial catheter-packing solutions hold promise for reduction of CRB. Treatment of CRB with antibiotics alone yields poor results and may increase the risk for other infectious complications, especially endocarditis. In selected cases where initial infection control can be achieved with antibiotics, guidewire exchange of the TDC results in cure rates equivalent to those of TDC removal and subsequent replacement. Dialysis programs should monitor TDC infections with attention to incidence, bacteriology, and outcomes.

Bacteremia is a frequent complication associated with tunneled, cuffed, permanent catheters (PCs). The incidence, spectrum of infecting organisms, and optimal treatment for catheter-associated bacteremia (CAB) have not been clearly established. In this study, 101 chronic hemodialysis (HD) patients with PCs for blood access were prospectively monitored for infection during a 24-month period. Data recorded for each patient included the number of catheter-days, episodes of suspected bacteremia, blood culture results, method of treatment, complications, and outcomes. All patients with CAB were treated with a 21-day course of intravenous antibiotics. The PC was removed if the patient had uncontrolled sepsis or if other vascular access was ready for use. Once the infection was controlled, catheter salvage was attempted, either by exchanging for a new catheter over a guidewire or treating with antibiotics only, leaving the original PC in place. Catheter exchange was the recommended approach in our program, but this was decided in each case by the treating nephrologist. During this study, there were 15,581 catheter-days, with 86 episodes of CAB, or 5.5 episodes/1,000 catheter-days (95% confidence interval, 4.5 to 6.8/1,000 d). Forty-five infections (52.3%) were caused by gram-positive cocci only, including Staphylococcus aureus, coagulase-negative Staphylococcus, and Enterococcus species. Twenty-three infections (26.7%) were caused by gram-negative rods only, including a wide variety of enteric organisms. Eighteen infections (20.9%) were polymicrobial. Thirty-nine of 86 episodes (45.3%) included at least one gram-negative organism. Five PCs were removed because of severe uncontrolled sepsis, and eight PCs were removed because they were no longer required. Of the remaining 73 cases, attempted PC salvage was successful in 11 of 30 patients (36.7%) treated with antibiotics alone versus 35 of 43 patients (81.4%) who underwent PC exchange in addition to antibiotic therapy (P = 0.0005). The only important complication of CAB was endocarditis, occurring in 3 of 86 episodes (3.5%). We conclude that in our HD units, CAB is relatively common and frequently involves gram-negative bacteria. PC salvage is significantly improved when antibiotic treatment is combined with PC exchange over a guidewire.

In the United States, there is a large and growing population of patients undergoing dialysis because of end-stage renal disease (ESRD). These patients present special management considerations for dentists, including antibiotic prophylaxis for the prevention of bacterial endocarditis (BE). ESRD patients, particularly those with an arteriovenous shunt for hemodialysis access, are predisposed to valvular endocarditis. Thus, BE prevention is the primary goal of antibiotic prophylaxis prior to dental or other invasive procedures in these patients. Bacteremia may predispose to infection of synthetic vascular access grafts, although this form of endovascular infection in ESRD patients has not been as well-characterized as BE. Antibiotic prophylaxis may be of some benefit for prevention of synthetic graft infections as well as BE. Poor dentist and physician compliance with BE prophylaxis regimens, as well as errors in dosing, timing, or duration of prophylaxis, have been reported. These problems are of particular concern in the treatment of chronically ill patients. In this article, we review the rationale for prophylactic antibiotic therapy prior to dental procedures in ESRD patients with vascular access. We also elaborate on the current American Heart Association guidelines for BE prophylaxis, and address special considerations for ESRD patients.