Juxta-anastomotic Stenoses Research Articles

The Retrograde Basilic Approach for Balloon-Assisted Maturation of Brachiocephalic Arteriovenous Fistulas

PurposeTo assess the feasibility and outcomes of an approach utilizing transbasilic access for balloon-assisted maturation (BAM) of brachiocephalic arteriovenous fistulas (BCAVFs). Materials and MethodsThis retrospective analysis comprised 28 patients (mean age, 63 years ± 10.8) who underwent endovascular treatment of their immature BCAVFs via a basilic approach from December 2016 to December 2018. The mean age of the BCAVFs was 3.3 months ± 1.4 at the time of BAM. Other demographic data, vascular access characteristics, procedural data, technical and clinical success rates, and adverse events were also evaluated. ResultsAll patients had inflow juxta-anastomotic stenoses, with 4 patients (14%) having concomitant outflow tract stenoses and 1 patient (4%) having a short-segment occlusion at the stenotic juxta-anastomotic segment. Technical success was achieved in 27 patients (96%). The mean diameter of the largest balloon used was 5.7 mm ± 0.6. Clinical success was achieved in 22 patients (79%), with 6 patients (21%) requiring a subsequent additional intervention before successful cannulation. No perioperative adverse events were observed. ConclusionsThe retrograde basilic approach is feasible, safe, and effective for BAM of BCAVFs.

Outcomes of endovascular procedures in salvage of arteriovenous fistulas via the transradial route: A prospective study

Aim: To evaluate the primary patency and predictors of technical failure of arteriovenous fistulae (AVF) following transradial percutaneous transluminal angioplasty (PTA). Materials and Methods: This was a prospective study being conducted to evaluate the primary patency and predictors of technical failure of AVF following transradial PTA. This will help us identify high-risk patients and plan interventions in them at an earlier time to avoid access loss. The time period of the study was from October 2016 to October 2018 in the Department of Vascular and Endovascular Surgery at Sri Ramachandra Medical College, Chennai, Tamil Nadu. A total of 44 patients were included in this cohort and they were all followed up in the outpatient department and via telephonic contact for a period of 1 year. All the patients who underwent endovascular AVF salvage fitting the inclusion criteria were included in the study. The demographics of the patients were recorded at admission and patients were investigated for the cause of fistula dysfunction at the treating physicians discretion and an ultrasound Doppler was ordered for all patients to ascertain the cause of the stenosis. The statistical analysis was done by the ANOVA and t-test. Results: A total of 44 patients were included in this cohort and they were all followed up for a period of 1 year. The 30-day, 90-day, 6-month, and 12-month primary patencies were 84.1%, 81.8%, 63.63%, and 43.18%, respectively. Our technical success was 88.6%. In our study, we found that longer lesion lengths (>4 cm) were prone to early loss of primary patency and this was statistically significant. We found that patients above 60 years of age had lower primary patencies and the presence of diabetes mellitus also lowered the primary patency. Fistula maturation age did not show a correlation with patency in our cohort. Male patients had a higher patency rate and juxta-anastomotic stenoses postangioplasty had a higher primary patency due to the shorter lengths. Radiocephalic fistula angioplasties had a higher patency as compared to brachiocephalic angioplasty. Conclusion: Ours is the first study in India to proactively and preferably use the transradial approach over the transvenous approach, as it confers many benefits. The challenges of the transradial route are the smaller size of the radial artery in the Indian population as compared to the western population.

Drug-Eluting Balloon Angioplasty for Juxta-Anastomotic Stenoses in Distal Radiocephalic Hemodialysis Fistulas: Long-Term Patency Results.

To evaluate long-term primary and secondary patency results of drug-eluting balloon angioplasty for the treatment of juxta-anastomotic stenoses in distal radiocephalic arteriovenous fistulas. Thirty-eight patients with juxta-anastomotic stenotic distal radiocephalic arteriovenous fistulas who underwent endovascular treatment with drug-eluting balloons between January 2014 and August 2016 in our interventional radiology department were included in this retrospective study. Color Doppler examination for follow-up was performed 15days, 6months, 12months, 18months, 24months, 36months, and 48months after the procedure. Kaplan-Meier analysis was used to estimate primary and secondary patency rates. Totally, 42 angioplasty with drug-eluting balloons was performed in 38 patients (20 men and 18 women; mean age 66.42 ± 12.01). Technical and clinical success rate was 100% (42/42). The mean follow-up period was 27.71months ± 12.98 (range, 1-54months). The estimated primary patency rates at 6months were 94.7% (95% CI, 80.9%-99.0%), at 12months were 81.2% (95% CI, 64.6%-91.4%), at 24months were 60.7% (95% CI, 43.6%-75.7%), and at 48months were 53.1% (95% CI, 36.5%-69.1%). The estimated secondary patency rates at 6months were 97.3% (95% CI, 84.5%-99.8%), at 12months were 86.5% (95% CI, 70.7%-94.8%), at 24months were 69.0% (95% CI, 51.8%-82.4%), and at 48months were 61.7% (95% CI, 44.6%-76.5%). Drug-eluting balloon angioplasty is a useful, effective technique in dysfunctional radiocephalic fistulas due to juxta-anastomotic stenoses. We demonstrated remarkably high primary patency rates at 6, 12, 24, and 48months.

Preemptive open surgical vs. endovascular repair for juxta-anastomotic stenoses of autogenous AV fistulae: a meta-analysis.

There is controversy about the best mode of preemptive repair of juxta-anastomotic stenoses in radial-cephalic arteriovenous fistula (AVFs). The aim of the present review was to compare the outcome of surgical vs. endovascular repair of those AVF stenoses. A systematic review and meta-analysis was performed for studies comparing the outcome of open surgical vs. endovascular preemptive repair of AVF stenoses located in the juxta-anastomotic region. A search was carried out in April 2015. The analyzed outcome measures were the primary patency at 12 and 18 months and the assisted primary patency at 24 months. In addition, assessment of the methodological quality of the included studies was carried out. Four non-randomized cohort studies (297 patients) were analyzed. A random effects model was used to pool the data. The pooled odds ratio (OR and 95% confidence intervals) for the primary patency at 12 and at 18 months was 0.42 (0.25-0.72) and 0.33 (0.2-0.56), respectively, showing statistically significant higher patency of the surgically repaired group. The pooled OR for the assisted primary patency at 24 months was 0.53 (0.28-0.98) also in favor of the surgically repaired group (p<0.04). The available evidence, based on non-randomized cohort studies, suggests that surgery is the best way to treat 'juxta-anastomotic' stenotic lesions in distal radial-cephalic AVFs, although angioplasty remains a valuable but less durable option in this location of the stenosis.

Transradial approach for percutaneous intervention of malfunctioning arteriovenous accesses

Interventions on arteriovenous (AV) access are typically performed with a direct puncture into the fistula. An alternative is the transradial approach (TRA), which offers the advantage of visualizing both the arterial and venous limbs as well as any juxta-anastomotic stenosis, all through one access. From September 2010 to 2013, 511 fistulograms were performed on 322 patients, 55 of which were TRA procedures in 40 patients (50% male; mean age, 60.4 ± 16.5 years). Of these, 37 of 40 accesses (92.5%) were AV fistulas, and 54 of 55 interventions (98%) were performed for stenotic lesion(s). There were 37 initial interventions, 13 secondary inventions, and five diagnostic fistulograms through the TRA. Stenotic lesions were juxta-anastomotic in 28, venous in 11, or both in 11. Mean follow-up was 14.3 months in 37 of 40 patients. Outcomes included technical and clinical success, complications, functional patency, and flow rate changes. All TRA punctures were successful, with no radial artery thromboses or hand ischemia. Technical success was 88% (44 of 50). Functional patency rates were 88.5% (23 of 26), 84.2% (16 of 19), and 83% (10 of 12) at 1, 6, and 12 months, respectively. The complication rate was 1.8% (one of 55), consisting of AV fistula rupture after angioplasty. The average flow rate in the 20 juxta-anastomotic stenosis increased from 637 mL/min to 1094 mL/min (P = .01) after the procedure. The TRA is a practical option with functional patency rates that are comparable to traditional approaches when intervening on a malfunctioning dialysis access in the appropriately selected patient. No hand ischemia was noted. This approach may be particularly attractive for treatment of juxta-anastomotic stenoses in a variety of AV accesses and offers unique practical advantages for the maintenance of AV accesses.

Drug-Eluting Balloon for the Treatment of Failing Hemodialytic Radiocephalic Arteriovenous Fistulas: Our Experience in the Treatment of Juxta-Anastomotic Stenoses

The purpose of this article is to report our experience with drug-eluting balloons for the treatment of juxta-anastomotic stenoses of failing radiocephalic hemodialytic arteriovenous shunt and to evaluate the primary and secondary patency (PP and SP). After approval by the local hospital's Ethical and Scientific Review Board, 26 consecutive patients with juxta-anastomotic stenosis of radiocephalic hemodialytic shunt were treated with angioplasty with drug-eluting balloon. The main objective was to evaluate PP defined, in accordance with the Kidney Disease Outcomes Quality Initiative recommendation, as the absence of dysfunction of the vascular access, patent lesion or residual stenosis <30% and no need for further reintervention of the target lesion (TL). PP and SP at 6, 12 and 24 months were evaluated, with echo color doppler and phlebography, for both arteriovenous fistulae, defined as absolute, and TL. Immediate postprocedural technical and clinical success was 100% for all the patients; we had only one technical failure in repeated treatments. At 6 months the absolute and TL PP was 96.1%; at 12 months the absolute PP was 81.8%, TL PP 90.9%, absolute SP 95.4%, TL SP 100%; at 24 months the absolute and TL PP was 57.8%; absolute and TL SP 94.7%; only one arteriovenous fistula was lost during the period. The use of drug-eluting balloons, after standard angioplasty, improves primary patency and decreases reinterventions of TL in juxta-anastomotic stenoses of failing native dialytic arteriovenous shunts.

Endovascular Treatment of Juxta-anastomotic Venous Stenoses of Forearm Radiocephalic Fistulas: Long-term Results and Prognostic Factors

PurposeTo evaluate long-term results of endovascular procedures in treatment of venous juxta-anastomotic stenoses (JASs) of native forearm radiocephalic arteriovenous fistulas (AVFs) and to identify prognostic factors influencing these results. Materials and MethodsDuring a 124-month period, 147 endovascular interventions were performed in 75 forearm radiocephalic AVFs with JASs defined as stenoses located within the first 5 cm of the outflow vein. Prognostic factors included patient characteristics (age, sex, diabetes), AVF-related characteristics (location on forearm, age, maturity), stenosis-related characteristics (position relative to anastomosis, length, and degree), and degree of residual stenosis and delay of restenosis after the first endovascular procedure. ResultsAt 1 and 3 years, access primary patency (PP) rates were 46.6% (95% confidence interval [CI], 36.3%–59.9%) and 25.5% (95% CI, 15.7%–41.6%) and assisted PP (APP) rates were 81.3% (95% CI, 72.6%–91.1%) and 63.2% (95% CI, 50.6%–79.0%), respectively. Stenosis degree of 50%–75% (P = .017), stenosis length of 10 mm or more (P = .017), and time before first restenosis of less than 6 months (P = .03) significantly increased the frequency of endovascular procedures during follow-up. However, only the degree of residual stenosis after the first endovascular treatment significantly affected long-term APP (P = .039). When residual stenosis was less than 50%, 1- and 2-year access APP rates were 84.6% (95% CI, 75.8%–94.4%) and 76.1% (95% CI, 64.6%–89.6%), respectively. When it was at least 50%, the respective APP rates were 62.3% (95% CI, 38.9%–99.9%) and 46.8% (95% CI, 22.4%–97.7%). ConclusionsEndovascular treatment of JASs in forearm radiocephalic AVFs provides good long-term results except when the residual stenosis after the first procedure is 50% or more. In that case, the optimal treatment remains to be determined.

Endovascular Interventions of Juxtaanastomotic Stenoses and Thromboses of Hemodialysis Arteriovenous Fistulas

To assess the primary and secondary patency rates for juxtaanastomotic stenoses, with or without superimposed thromboses, of arteriovenous hemodialysis fistulas treated with angioplasty and to compare it with National Kidney Foundation Dialysis Outcomes Quality Initiative treatment guidelines for stenosed and occluded arteriovenous fistulas (50% primary patency rate at 12 months). This study was a retrospective analysis, covering a period of 5(1/2) years. Forty-three hemodialysis patients were referred due to secondary fistula dysfunction, and angiography was diagnostic of a juxtaanastomotic lesion. Interventions consisted of standard angioplasty techniques along with thrombolysis and/or thrombectomy and intravascular stent placement as needed. Follow-up was performed at the attending dialysis center, and repeat angiography was performed as clinically required. Immediate postprocedural angiography demonstrated an angiographic success rate of 98%. Clinical success, with at least one session of normal dialysis, occurred in 95% of interventions. Primary patency rates at 12 months for the stenosed and stenosed/thrombosed fistulas were 56% and 64%, respectively. Secondary patency rates at 12 months were 64% and 63%, respectively. Half of the stenosed fistulas were patent at 1.5 years, 28% were patent at 4 years, and 13% remained patent at 6 years. No major complications were documented. Four minor complications, which did not require therapy, were noted. The results achieved are comparable to those reported for interventions at nonjuxtaanastomotic sites and exceed those quoted by the National Kidney Foundation Dialysis Outcomes Quality Initiative guidelines. Angioplastic interventions in a juxtaanastomatic area of arteriovenous fistulas are safe, promote prolonged patency, and postpone the need for surgical intervention or creation of a new fistula.

Endovascular versus Surgical Preemptive Repair of Forearm Arteriovenous Fistula Juxta-Anastomotic Stenosis

Surgery is the traditional treatment for juxta-anastomotic stenoses in forearm arteriovenous fistulas (AVF), but percutaneous transluminal angioplasty (PTA) is a suitable alternative. No prospective comparative trials between the two have been reported to date, however. A retrospective analysis of prospectively, concurrently collected data was performed to compare the outcome and cost of surgery and PTA in the preemptive repair of juxta-anastomotic stenosis in lower forearm AVF. Sixty-four AVF with >50% venous juxta-anastomotic stenosis were considered: 21 were treated surgically (11 proximal neo-anastomosis and 10 polytetrafluoroethylene interposition graft) and 43 by PTA. After treatment, AVF were monitored by quarterly ultrasound dilution access blood flow measurement. End points were restenosis and procedure failure rate (re-intervention by another technique or access loss), and determinants were analyzed using Cox hazard model. Initial procedural success was 100% for surgery and 95% for PTA (P = 0.539). Restenosis rate was 0.168 and 0.519 events/AVF-year for surgery and PTA, respectively (P = 0.009). The type of procedure was the only variable that was significantly associated with restenosis, the adjusted relative risk being 2.77-fold higher (95% confidence interval 1.07 to 7.17; P = 0.036) after PTA than surgery. The procedure failure rate was 0.110 and 0.097 events/AVF-year for surgery and PTA, respectively (P = 0.736). The cost profile also was similar for the two procedures. This prospective comparative study confirms a higher restenosis rate after PTA than surgery, but with strict surveillance for restenosis, the two procedures show similar assisted primary patency and cost, suggesting that they should be considered equally valid, complementary alternatives in the preemptive treatment of juxta-anastomotic stenosis in forearm AVF.

Endothelial Progenitor Cells, Neointimal Hyperplasia, and Hemodialysis Vascular Access Dysfunction

Vascular stenosis as a result of neointimal hyperplasia is a major clinical problem that has an impact on multiple and diverse disciplines, including cardiology (coronary restenosis), cardiothoracic and vascular surgery (saphenous vein and polytetrafluoroethylene [PTFE] graft failure), neurology (carotid stenosis), nephrology (dialysis access dysfunction), and transplant medicine (chronic allograft rejection in hearts and kidneys). The traditional response to injury hypothesis on the pathogenesis of neointimal hyperplasia focuses on the migration of medial smooth muscle cells from the media into the intima.1 Recently, there has been a great deal of excitement about the role of circulating smooth muscle progenitor cells in the pathogenesis of neointimal hyperplasia. These cells have been identified in a variety of experimental models of vascular injury,2 and interventions that reduce the number of these cells can attenuate neointimal hyperplasia. In marked contrast to the deleterious effects of smooth muscle progenitor cells on neointimal hyperplasia, circulating endothelial progenitor cells (EPCs) are believed to play an important role in vascular repair and in the inhibition of neointimal hyperplasia.3 See p 12 In this issue of Circulation , Rotmans and colleagues have attempted to achieve the “holy grail” for a vascular access procedure: rapid and complete endothelialization.4 Their experiments are based on a newly developed technique that can coat the surface of stent and graft material with antibodies against CD34 (Orbus Medical Technologies). CD34 is a marker for hematopoietic stem cells, and previous research has demonstrated that coronary stents coated with anti-CD34 have a significant increase in endothelialization as early as 1 hour after deployment because of the binding of circulating CD34+ cells, which then differentiate into endothelial cells.5 Placement of anti-CD34–coated grafts in an arteriovenous model of PTFE graft stenosis by Rotmans et al resulted in almost complete endothelialization of the grafts (both …

Five-Years' Experience with Revision of Failing Peripheral Vein Bypasses

The aim of this study was to assess the results of surgical and endovascular treatment of failing or failed infrainguinal vein bypasses. Eight hundred seventy-five patients with peripheral vein bypasses performed during a 5-year period were followed up prospectively by ankle blood pressure measurements and/or duplex scanning at 3, 6, 9, 12, 18, 24, 36, and 48 months. A total of 59 (7%) grafts required revision during the study period. Fifty-six juxtaanastomotic or intragraft stenoses in 46 failing but patent bypasses were electively revised. Thirty-one predominantly proximal and midgraft lesions in 28 grafts were treated surgically by patch angioplasty (n= 17), interposition/jump grafting (n= 10), or thromboendarterectomy (n= 4). Twenty-five predominantly distal stenoses in 18 grafts were treated by percutaneous transluminal balloon angioplasty (PTA). With this approach, surgery yielded a higher 12-month “primary” bypass patency after revision (72% vs 37%, P=0.02), a higher secondary patency (81% vs 48%, P=0.05) and a better limb survival (96% vs 64%, P=0.03) than PTA. Following thrombectomy (n=12) or thrombolysis (n= 1) of 13 occluded bypasses, a 6-month “primary” patency after revision of 31%, a secondary patency of 38%, and a limb survival of 61% were achieved. In conclusion surgical repair appears to be the most durable procedure in the management of threatened infrainguinal vein bypasses. PTA of distal vein graft lesions was associated with a high risk of restenosis and graft failure.