Anti-tubular basement membrane disease (aTBM disease) produces T cell-mediated interstitial nephr... more Anti-tubular basement membrane disease (aTBM disease) produces T cell-mediated interstitial nephritis in SJL mice after immunization with renal tubular antigen. Initial mononuclear infiltrates appear in vivo after several weeks, with the subsequent progression to renal fibrosis and end stage renal disease over many months. We have analyzed the fine specificity of the autoreactive helper T cell repertoire in aTBM disease through the isolation and characterization of a panel of CD4 + Thl clones harvested after 1-2 wk from animals immunized to produce disease. All clones capable of mediating aTBM disease are directed towards a 14-residue immunodominant epitope (STMSAEVPEAASEA) contained within the target antigen, 3M-1. Evaluation of the T cell receptor (TCR) V13 repertoire used by these autoreactive T cells reveals the use of several Vj3 genes, but with some preference for VB14. Sequencing across the putative CDR3 region of the TCR (8 chains suggests that common amino acids at the V(3(N)D(3 junction and the Dfi(N)Jj3 junction may contribute to the specific ability of these cells to recognize the immunodominant epitope.
T he role of neointimal hyperplasia in the failure of arteriovenous (AV) access has been firmly e... more T he role of neointimal hyperplasia in the failure of arteriovenous (AV) access has been firmly established over many decades. Conventional balloon angioplasty (percutaneous transluminal angioplasty [PTA]) has long been the standard of care for minimally invasive treatment of stenosis. However, angioplasty does nothing to interrupt the fundamental pathophysiology of neointimal hyperplasia and, in fact, may accelerate the process due to injury-induced mediators of cellular proliferation. Drug-coated balloon (DCB) angioplasty, particularly with the antiproliferative agent paclitaxel, has been shown to reduce neointimal hyperplasia and reduce lesion restenosis in a variety of vascular applications. Clinical studies have demonstrated outcome benefit when DCBs are used to treat stenosis occurring in AV access.1 The recently completed Lutonix AV clinical trial demonstrated a significant reduction in the frequency of reintervention after DCB PTA, consistent with paclitaxel’s known mechanis...
Cardiovascular implantable electronic devices (CIEDs) are frequently utilized in hemodialysis pat... more 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 p...
In the United States, there is a large and growing population of patients undergoing dialysis bec... more In the United States, there is a large and growing population of patients undergoing dialysis because of enoFstage 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 hernodialysis 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 graffs, although this form of endovascular infection in ESRD patients has not been as wellcharacterized as BE. Antibiotic prophylaxis may be of some benefit for prevention of synthetic graff hfi?ctions 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 considera tions for ESRD patients.
ASDIN) was founded in the year 2000 to promote the procedural aspects of nephrology through educa... more ASDIN) was founded in the year 2000 to promote the procedural aspects of nephrology through education, training, research, certification, and accreditation. Currently the society is focusing on four areas: sonography of the kidneys and bladder, hemodialysis catheters, peritoneal catheters, and endoluminal procedures on hemodialysis accesses. Committees were formed to develop criteria for training, certification, and accreditation in each of these areas. Members of each committee are listed on the society's website: . ASDIN.org. These criteria were then adopted as formal guidelines by the full membership. ''Guidelines for Training, Certification, and Accreditation in Placement of Permanent Tunneled and Cuffed Peritoneal Dialysis Catheters'' and ''Guidelines for Training, Certification, and Accreditation in Renal Sonography'' were published in the November-December 2002 issue of Seminars in Dialysis. This issue contains the ''Guidelines for Hemodialysis Vascular Access Endovascular Procedures.'' Guidelines are presented for both certification of individual physicians and accreditation of training programs. Once certain legal and liability issues are resolved, the society will begin accepting applications for certification and accreditation. The society is now accepting applications for certification and accreditation.
Heart & Lung: The Journal of Acute and Critical Care, 2012
An increasing number of patients are being treated with cardiovascular implantable electronic dev... more An increasing number of patients are being treated with cardiovascular implantable electronic devices (CIEDs), many of which are MR conditional. There is a lack of literature on the safe scanning of MR conditional CIEDs. This review article discusses MR imaging safety in patients with implanted CIEDs. Guidelines on safe use and indications of imaging patients with MR conditional CIEDs are described, followed by a pictorial essay of the radiographic features of these devices. We also discuss the challenges of monitoring the patient in the MR environment, advances in MRI conditional imaging of devices, availability, limitations and workflow including vendor-specific and other collaborative efforts to simplify the scanning process. Radiologists must be able to facilitate the safe utilization of MR imaging in patients who have CIEDs. A thorough knowledge of the hazards of imaging non-MR compatible devices is required as well as knowing how to correctly identify and manage the imaging of patients with MR conditional CIEDs. Finally, we propose steps required to facilitate the safe scanning of patients with MR conditional CIEDs adopted in our institution and a contingency plan in the event that an inadvertent MR scan of a patient with a MRI unsafe CIED should occur. Main Messages • Risks of MR imaging in patients who have CIEDs have been worked around. • There are many technical limitations in enabling safe MR scanning of CIEDs. • Radiological identification of MRI-conditional status of CIEDs is useful. • Standardizing conditions for safe MRI scanning is important. • We offer example algorithms for facilitating safe MRI scanning of CIEDs.
Current Opinion in Nephrology and Hypertension, 1996
Vascular access complications remain a leading cause of morbidity and hospitalization in patients... more Vascular access complications remain a leading cause of morbidity and hospitalization in patients on chronic maintenance hemodialysis. Although arteriovenous fistulas remain the dialysis access of choice, an increasing percentage of patients are dialyzed using synthetic grafts or permanent catheters. The most frequent vascular access complications are the development of stenosis and of thrombosis. In recent years, increasing attention is being paid to screening techniques designed to detect vascular access stenosis prior to thrombosis. Aggressive screening techniques coupled with interventional procedures such as angioplasty may reduce the incidence of graft thrombosis. Once thrombosis has occurred, mechanical or pharmacomechanical thrombolysis in conjunction with angioplasty may be an effective alternative to surgical thrombectomy.
Bacteremia is a frequent complication associated with tunneled, cuffed, permanent catheters (PCs)... more 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.
This commentary uses the negative results of the PAVE (Paclitaxel-coated Balloons and Angioplasty... more 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.
Saudi Journal of Kidney Diseases and Transplantation
Over the past decade, there has been increasing interest and participation by nephrologists in th... more Over the past decade, there has been increasing interest and participation by nephrologists in the management of hemodialysis vascular access. Since the inception of chronic hemodialysis therapy, there has been a curious evolution of the nephrologists' role in the management of vascular access. The early days of dialysis were marked by advances in vascular access conceived and developed by visionary nephrologists, including the Scribner shunt 1 and the Brescia-Cimino arteriovenous fistula. 2,3 Some nephrologists have maintained this primary role in vascular access creation and maintenance, particularly in Europe, with Dr Klaus Konnor's experience standing out as a shining example. 4 During the 1970's and 80's, at least in the United States (US), nephrologists' interest and involvement in vascular access largely faded. This may have been due to progress in what was perceived as more scientifically rewarding areas of study. Certainly, neither technical
To present final, 2-year results of a randomized trial comparing paclitaxel-coated vs uncoated ba... more 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 ¼ .02) at 9 months, 44% ± 5 vs 36% ± 4 (P ¼ .04) at 12 months, 34% ± 5 vs 28% ± 4 (P ¼ .06) at 18 months, and 27% ± 4 vs 24% ± 4 (P ¼ .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 ¼ .02) but not at 12 (P ¼ .08), 18 (P ¼ .13), or 24 months (P ¼ .19). The noninferiority safety target was met at all intervals (P < .01). Mortality did not differ between groups (P ¼ .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. ABBREVIATIONS ACPP ¼ access circuit primary patency, AVF ¼ arteriovenous fistula, AVG ¼ arteriovenous graft, CONSORT ¼ Consolidated Standards of Reporting Trials, DCB ¼ drug-coated balloon, ESRD ¼ end-stage renal disease, RVD ¼ reference vessel diameter, TLP ¼ target lesion patency, TLPP ¼ target lesion primary patency Improving outcomes in access maintenance percutaneous transluminal angioplasty (PTA) is a highly desirable goal, given the modest outcomes afforded by standard PTA and the burgeoning cost of access creation and maintenance (1,2). Although it remains controversial whether maintenance PTA prolongs access life (3-6), maintenance PTA reduces the thrombosis rate and associated hospitalization, catheter placement, and missed dialysis sessions (7-9). In addition to
Clinical Journal of the American Society of Nephrology
BackgroundRestenosis remains a problem in hemodialysis access interventions. Paclitaxel-coated ba... more BackgroundRestenosis 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, & measurementsThis 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’ usu...
End-stage renal disease is frequently accompanied by cardiac comorbidity that warrants treatment ... more End-stage renal disease is frequently accompanied by cardiac comorbidity that warrants treatment with a cardiovascular implantable electronic device (permanent pacemaker or implantable cardioverter-defibrillator). In the United States, chronic hemodialysis (HD) population, cardiac implantable devices are present in up to 10.5% of patients; a venous HD catheter is utilized for blood access in 18% of prevalent patients. The concomitant presence of a venous HD catheter and cardiovascular implantable device creates a high-risk circumstance, with potential for causing symptomatic central venous stenosis, and for developing complicated endovascular infection. This dangerous combination may be avoided for many patients by utilizing nondialysis methods for management of advanced chronic kidney disease, initiating dialysis without venous catheter access, or managing cardiac rhythm disorders without use of transvenous cardiac implantable electronic devices. In those situations where the combination of a venous HD catheter and cardiac implantable device is unavoidable, there are strategies to minimize duration of venous catheter access, and to reduce risks for infectious complications. It is essential for nephrologists and cardiologists to understand the indications, alternatives, and risks involved with venous HD access and cardiac implantable devices. Coordinated management of renal disease and cardiac rhythm disorders has potential to minimize risks, improve outcomes, and substantially reduce the cost of care.
Anti-tubular basement membrane disease (aTBM disease) produces T cell-mediated interstitial nephr... more Anti-tubular basement membrane disease (aTBM disease) produces T cell-mediated interstitial nephritis in SJL mice after immunization with renal tubular antigen. Initial mononuclear infiltrates appear in vivo after several weeks, with the subsequent progression to renal fibrosis and end stage renal disease over many months. We have analyzed the fine specificity of the autoreactive helper T cell repertoire in aTBM disease through the isolation and characterization of a panel of CD4 + Thl clones harvested after 1-2 wk from animals immunized to produce disease. All clones capable of mediating aTBM disease are directed towards a 14-residue immunodominant epitope (STMSAEVPEAASEA) contained within the target antigen, 3M-1. Evaluation of the T cell receptor (TCR) V13 repertoire used by these autoreactive T cells reveals the use of several Vj3 genes, but with some preference for VB14. Sequencing across the putative CDR3 region of the TCR (8 chains suggests that common amino acids at the V(3(N)D(3 junction and the Dfi(N)Jj3 junction may contribute to the specific ability of these cells to recognize the immunodominant epitope.
T he role of neointimal hyperplasia in the failure of arteriovenous (AV) access has been firmly e... more T he role of neointimal hyperplasia in the failure of arteriovenous (AV) access has been firmly established over many decades. Conventional balloon angioplasty (percutaneous transluminal angioplasty [PTA]) has long been the standard of care for minimally invasive treatment of stenosis. However, angioplasty does nothing to interrupt the fundamental pathophysiology of neointimal hyperplasia and, in fact, may accelerate the process due to injury-induced mediators of cellular proliferation. Drug-coated balloon (DCB) angioplasty, particularly with the antiproliferative agent paclitaxel, has been shown to reduce neointimal hyperplasia and reduce lesion restenosis in a variety of vascular applications. Clinical studies have demonstrated outcome benefit when DCBs are used to treat stenosis occurring in AV access.1 The recently completed Lutonix AV clinical trial demonstrated a significant reduction in the frequency of reintervention after DCB PTA, consistent with paclitaxel’s known mechanis...
Cardiovascular implantable electronic devices (CIEDs) are frequently utilized in hemodialysis pat... more 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 p...
In the United States, there is a large and growing population of patients undergoing dialysis bec... more In the United States, there is a large and growing population of patients undergoing dialysis because of enoFstage 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 hernodialysis 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 graffs, although this form of endovascular infection in ESRD patients has not been as wellcharacterized as BE. Antibiotic prophylaxis may be of some benefit for prevention of synthetic graff hfi?ctions 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 considera tions for ESRD patients.
ASDIN) was founded in the year 2000 to promote the procedural aspects of nephrology through educa... more ASDIN) was founded in the year 2000 to promote the procedural aspects of nephrology through education, training, research, certification, and accreditation. Currently the society is focusing on four areas: sonography of the kidneys and bladder, hemodialysis catheters, peritoneal catheters, and endoluminal procedures on hemodialysis accesses. Committees were formed to develop criteria for training, certification, and accreditation in each of these areas. Members of each committee are listed on the society's website: . ASDIN.org. These criteria were then adopted as formal guidelines by the full membership. ''Guidelines for Training, Certification, and Accreditation in Placement of Permanent Tunneled and Cuffed Peritoneal Dialysis Catheters'' and ''Guidelines for Training, Certification, and Accreditation in Renal Sonography'' were published in the November-December 2002 issue of Seminars in Dialysis. This issue contains the ''Guidelines for Hemodialysis Vascular Access Endovascular Procedures.'' Guidelines are presented for both certification of individual physicians and accreditation of training programs. Once certain legal and liability issues are resolved, the society will begin accepting applications for certification and accreditation. The society is now accepting applications for certification and accreditation.
Heart & Lung: The Journal of Acute and Critical Care, 2012
An increasing number of patients are being treated with cardiovascular implantable electronic dev... more An increasing number of patients are being treated with cardiovascular implantable electronic devices (CIEDs), many of which are MR conditional. There is a lack of literature on the safe scanning of MR conditional CIEDs. This review article discusses MR imaging safety in patients with implanted CIEDs. Guidelines on safe use and indications of imaging patients with MR conditional CIEDs are described, followed by a pictorial essay of the radiographic features of these devices. We also discuss the challenges of monitoring the patient in the MR environment, advances in MRI conditional imaging of devices, availability, limitations and workflow including vendor-specific and other collaborative efforts to simplify the scanning process. Radiologists must be able to facilitate the safe utilization of MR imaging in patients who have CIEDs. A thorough knowledge of the hazards of imaging non-MR compatible devices is required as well as knowing how to correctly identify and manage the imaging of patients with MR conditional CIEDs. Finally, we propose steps required to facilitate the safe scanning of patients with MR conditional CIEDs adopted in our institution and a contingency plan in the event that an inadvertent MR scan of a patient with a MRI unsafe CIED should occur. Main Messages • Risks of MR imaging in patients who have CIEDs have been worked around. • There are many technical limitations in enabling safe MR scanning of CIEDs. • Radiological identification of MRI-conditional status of CIEDs is useful. • Standardizing conditions for safe MRI scanning is important. • We offer example algorithms for facilitating safe MRI scanning of CIEDs.
Current Opinion in Nephrology and Hypertension, 1996
Vascular access complications remain a leading cause of morbidity and hospitalization in patients... more Vascular access complications remain a leading cause of morbidity and hospitalization in patients on chronic maintenance hemodialysis. Although arteriovenous fistulas remain the dialysis access of choice, an increasing percentage of patients are dialyzed using synthetic grafts or permanent catheters. The most frequent vascular access complications are the development of stenosis and of thrombosis. In recent years, increasing attention is being paid to screening techniques designed to detect vascular access stenosis prior to thrombosis. Aggressive screening techniques coupled with interventional procedures such as angioplasty may reduce the incidence of graft thrombosis. Once thrombosis has occurred, mechanical or pharmacomechanical thrombolysis in conjunction with angioplasty may be an effective alternative to surgical thrombectomy.
Bacteremia is a frequent complication associated with tunneled, cuffed, permanent catheters (PCs)... more 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.
This commentary uses the negative results of the PAVE (Paclitaxel-coated Balloons and Angioplasty... more 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.
Saudi Journal of Kidney Diseases and Transplantation
Over the past decade, there has been increasing interest and participation by nephrologists in th... more Over the past decade, there has been increasing interest and participation by nephrologists in the management of hemodialysis vascular access. Since the inception of chronic hemodialysis therapy, there has been a curious evolution of the nephrologists' role in the management of vascular access. The early days of dialysis were marked by advances in vascular access conceived and developed by visionary nephrologists, including the Scribner shunt 1 and the Brescia-Cimino arteriovenous fistula. 2,3 Some nephrologists have maintained this primary role in vascular access creation and maintenance, particularly in Europe, with Dr Klaus Konnor's experience standing out as a shining example. 4 During the 1970's and 80's, at least in the United States (US), nephrologists' interest and involvement in vascular access largely faded. This may have been due to progress in what was perceived as more scientifically rewarding areas of study. Certainly, neither technical
To present final, 2-year results of a randomized trial comparing paclitaxel-coated vs uncoated ba... more 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 ¼ .02) at 9 months, 44% ± 5 vs 36% ± 4 (P ¼ .04) at 12 months, 34% ± 5 vs 28% ± 4 (P ¼ .06) at 18 months, and 27% ± 4 vs 24% ± 4 (P ¼ .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 ¼ .02) but not at 12 (P ¼ .08), 18 (P ¼ .13), or 24 months (P ¼ .19). The noninferiority safety target was met at all intervals (P < .01). Mortality did not differ between groups (P ¼ .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. ABBREVIATIONS ACPP ¼ access circuit primary patency, AVF ¼ arteriovenous fistula, AVG ¼ arteriovenous graft, CONSORT ¼ Consolidated Standards of Reporting Trials, DCB ¼ drug-coated balloon, ESRD ¼ end-stage renal disease, RVD ¼ reference vessel diameter, TLP ¼ target lesion patency, TLPP ¼ target lesion primary patency Improving outcomes in access maintenance percutaneous transluminal angioplasty (PTA) is a highly desirable goal, given the modest outcomes afforded by standard PTA and the burgeoning cost of access creation and maintenance (1,2). Although it remains controversial whether maintenance PTA prolongs access life (3-6), maintenance PTA reduces the thrombosis rate and associated hospitalization, catheter placement, and missed dialysis sessions (7-9). In addition to
Clinical Journal of the American Society of Nephrology
BackgroundRestenosis remains a problem in hemodialysis access interventions. Paclitaxel-coated ba... more BackgroundRestenosis 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, & measurementsThis 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’ usu...
End-stage renal disease is frequently accompanied by cardiac comorbidity that warrants treatment ... more End-stage renal disease is frequently accompanied by cardiac comorbidity that warrants treatment with a cardiovascular implantable electronic device (permanent pacemaker or implantable cardioverter-defibrillator). In the United States, chronic hemodialysis (HD) population, cardiac implantable devices are present in up to 10.5% of patients; a venous HD catheter is utilized for blood access in 18% of prevalent patients. The concomitant presence of a venous HD catheter and cardiovascular implantable device creates a high-risk circumstance, with potential for causing symptomatic central venous stenosis, and for developing complicated endovascular infection. This dangerous combination may be avoided for many patients by utilizing nondialysis methods for management of advanced chronic kidney disease, initiating dialysis without venous catheter access, or managing cardiac rhythm disorders without use of transvenous cardiac implantable electronic devices. In those situations where the combination of a venous HD catheter and cardiac implantable device is unavoidable, there are strategies to minimize duration of venous catheter access, and to reduce risks for infectious complications. It is essential for nephrologists and cardiologists to understand the indications, alternatives, and risks involved with venous HD access and cardiac implantable devices. Coordinated management of renal disease and cardiac rhythm disorders has potential to minimize risks, improve outcomes, and substantially reduce the cost of care.
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