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Purpose: Arteriovenous fistulas (AVF) is the preferred type of hemodialysis access, but when an arteriovenous anastomosis (AVA) calcifies, surgical revision of the AVF may be required. We report a technique to create percutaneous artery-to-vein intervascular neo-fistulas for re-anastomosis of AVA and evaluate its safety and efficacy., Materials and Methods: 9 patients who failed either guidewire navigation or conventional balloon dilation for calcified AVA stenosis/occlusion underwent a salvage procedure of their dialysis shunt by the percutaneous creation of a new arteriovenous fistula. Needle puncture of the adjacent supplying artery and outflow vein under ultrasonographic and/or fluoroscopic guidance was performed and followed by balloon dilation, with or without stent graft placement. The detailed techniques, technical success, primary neo-fistula patency, primary and secondary access patency rates were reported herein., Results: Technical success was achieved in 100% of the 9 patients treated (7 neo-fistulas with stents and 2 neo-fistulas without stent placement). The median primary neo-fistula and access patencies were 15 and 5 months, respectively. The primary neo-fistula patency rates at 6, 12, and 18 months were 72.9%, 54.7% and 27.9%, respectively, with secondary neo-fistula and access patency rates of 72.9%, 72.9% and 72.9%, respectively. One delayed complication of pseudoaneurysm formation occurred, which was managed by the successful endovascular deployment of a stent graft on an out-patient basis., Conclusion: Percutaneous artery-to-vein intervascular neo-fistula creation is feasible for re-anastomosing calcified AVA, with low adverse effects and acceptable primary neo-fistula and secondary access patency., (© 2024. Springer Science+Business Media, LLC, part of Springer Nature and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE).)

Cephalic arch stenosis (CAS) is a common cause of AV dialysis access failure and is notoriously difficult to treat with conventional venoplasty. Although stent graft (SG) placement has improved patency rate, they are prone to stent failure caused by edge stenosis. We investigate the effect of SG diameter relative to cephalic vein on patency rate among hemodialysis patients with dysfunctional arteriovenous access caused by CAS. We identified 22 patients with recalcitrant cephalic arch stenosis or post-venoplasty vessel rupture and received SG placement. Patients were divided into two groups based on the stent-to-vessel diameter (S/V) ratio: undersized group, < 1; and apposed group, 1-1.2. Outcomes were assessed through follow-up angiography. S/V ratio was significant smaller in the undersized patient group (p < 0.001). Placement of undersized SG demonstrated higher primary stent (p = 0.001) and access patency rates (p = 0.021) and a reduced number of post-treatment reinterventions per access year (p = 0.021). A decreased number of lateral edge stenosis was noted in undersized SG (p = 0.005). Increased S/V ratio was significantly associated with lateral edge stenosis (OR = 5.19; p = 0.027). Undersized SG is associated with higher primary stent and access patency rate, and decreased number of post-SG interventions, and are suggested in the treatment of cephalic arch stenosis.

Purpose:: This study was performed to retrospectively assess the efficacy of percutaneous creation of an intervascular bypass with or without stent graft deployment (endovascular bypass) for salvage of abandoned vascular access sites in hemodialysis catheter-consigned patients., Methods:: Salvage of abandoned vascular access sites was attempted in 16 patients with hemodialysis catheters. These vascular access sites were salvaged using endovascular bypass techniques to redirect the access flow to a nonarterialized vein as a new outflow conduit or cannulation segment. The postintervention primary, assisted primary, and secondary patency rates of the access site and bypass were calculated using the Kaplan-Meier method., Results:: The procedural and clinical success rates were both 100%. The postintervention primary patency rate of the bypass and access site at 360 days was 75.7 ± 12.5% and 56.8 ± 14.9%, respectively. The mean follow-up period was 461.9 days (range: 121-900 days). No major complications were observed. One bare bypass tunnel rupture and one pseudoaneurysm were noted during the procedure., Conclusion:: Salvage of abandoned vascular access sites for hemodialysis catheter-consigned patients can be technically feasible and clinically successful using endovascular bypass techniques in selected patients when surgical revision is not considered or is not possible.

Purpose: To report the technical success and long-term clinical outcomes of immature arteriovenous fistula (AVF) after percutaneous angioplasty (PTA)., Materials and Methods: Patients with 58 immature AVF underwent PTA treatment in our institute during the past 9 years. Based on pretreatment ultrasound findings, the immature AVFs were categorized as stenosed, thrombosed, and obliterated type. An optimal entry site was punctured under ultrasound guidance followed by conventional fluoroscopy-guided PTA technique. Technical and clinical success as well as complications were recorded. Patency after angioplasty was estimated using Kaplan-Meier analysis. Predictors of patency were estimated using log-rank test., Results: In our series, 50 % (29 of 58), 20.7 % (12 of 58), and 29.3 % (17 of 58) of immature AVF were stenosed, thrombosed, and obliterated, respectively. Technical and clinical success was achieved in 96.6 % (56 of 58) of cases with 100 % success in both the stenosed and thrombosed lesions and 88.2 % (15 of 17) success in the obliterated lesions. Vascular ruptures occurred in 12.1 % (7 of 58) of lesions. The overall primary and secondary patency rates of the 58 lesions were 45.4 and 84.2 % at 12 months and 36.5 and 80.1 % at 36 months. There were no significant differences of patency between the three types of lesions (p = 0.075 and 0.093) and the two groups of patients with or without residual side branches after intervention (p = 0.527 and 0.644). There was a significant difference of primary patency in patients with vascular rupture (p = 0.012) with a hazard ratio of 3.236., Conclusion: PTA could effectively prolong the lifetime of immature AVFs with high technical success. Vessel rupture was predictive of shorter primary patency, and long-term secondary patency was acceptable.

Objective: The current study retrospectively evaluated whether the percutaneous N-butyl cyanoacrylate (NBCA) seal-off technique is an effective treatment for controlling the angioplasty-related ruptures, which are irresponsive to prolonged balloon tamponade, during interventions for failed or failing hemodialysis vascular accesses., Materials and Methods: We reviewed 1588 interventions performed during a 2-year period for dysfunction and/or failed hemodialysis vascular access sites in 1569 patients. For the angioplasty-related ruptures, which could not be controlled with repeated prolonged balloon tamponade, the rupture sites were sealed off with an injection of a glue mixture (NBCA and lipiodol), via a needle/needle sheath to the rupture site, under a sonographic guidance. Technical success rate, complications and clinical success rate were reported. The post-seal-off primary and secondary functional patency rates were calculated by a survival analysis with the Kaplan-Meier method., Results: Twenty ruptures irresponsive to prolonged balloon tamponade occurred in 1588 interventions (1.3%). Two technical failures were noted; one was salvaged with a bailout stent-graft insertion and the other was lost after access embolization. Eighteen accesses (90.0%) were salvaged with the seal-off technique; of them, 16 ruptures were completely sealed off, and two lesions were controlled as acute pseudoaneurysms. Acute pseudoaneurysms were corrected with stentgraft insertion in one patient, and access ligation in the other. The most significant complication during the follow-up was delayed pseudoaneurysm, which occurred in 43.8% (7 of 16) of the completely sealed off accesses. Delayed pseudoaneurysms were treated with surgical revision (n = 2), access ligation (n = 2) and observation (n = 3). During the follow-up, despite the presence of pseudoaneurysms (acute = 1, delayed = 7), a high clinical success rate of 94.4% (17 of 18) was achieved, and they were utilized for hemodialysis at the mean of 411.0 days. The post-seal-off primary patency vs. secondary patency at 90, 180 and 360 days were 66.7 ± 11.1% vs. 94.4 ± 5.4%; 33.3 ± 11.1% vs. 83.3 ± 8.8%; and 13.3 ± 8.5% vs. 63.3 ± 12.1%, respectively., Conclusion: Our results suggest that the NBCA seal-off technique is effective for immediate control of a venous rupture irresponsive to prolonged balloon tamponade, during interventions for hemodialysis accesses. Both high technical and clinical success rates can be achieved. However, the treatment is not durable, and about 40% of the completely sealed off accesses are associated with developed delayed pseudoaneurysms in a 2-month of follow-up. Further repair of the vascular tear site, with surgery or stent-graft insertion, is often necessary.

The current study retrospectively evaluated whether endovascular revascularization of chronically thrombosed and long-discarded vascular access sites for hemodialysis was feasible. Technical and clinical success rates, postintervention primary and secondary patency rates, and complications were reported. During a 1-year period, we reviewed a total of 924 interventions performed for dysfunction and/or failed hemodialysis vascular access sites and permanent catheters in 881 patients. In patients whose vascular access-site problems were considered untreatable or were considered treatable with a high risk of failure and access-site abandonment, we attempted to revascularize (resurrect) the chronically occluded and long-discarded (mummy) vascular access sites. We attempted to resurrect a total of 18 mummy access sites (mean age 46.6 ± 38.7 months; range 5-144) in 15 patients (8 women and 7 men; mean age 66.2 ± 11.5 years; age range 50-85) and had an overall technical success rate of 77.8%. Resurrection failure occurred in 3 fistulas and in 1 straight graft. The clinical success rate was 100% at 2 months after resurrection. In the 14 resurrected vascular access sites, 6 balloon-assisted maturation procedures were required in 5 fistulas; after access-site maturation, a total of 22 interventions were performed to maintain access-site patency. The mean go-through time for successful resurrection procedures was 146.6 ± 34.3 min (range 74-193). Postmaturation primary patency rates were 71.4 ± 12.1% at 30 days, 57.1 ± 13.2% at 60 days, 28.6 ± 13.4% at 90 days, and 19 ± 11.8% at 180 days. Postmaturation secondary patency rates were 100% at 30, 60, and 90 days and 81.8 ± 11.6% at 180 days. There were 2 major complications consisting of massive venous ruptures in 2 mummy access sites during balloon dilation; in both cases, prolonged balloon inflation failed to achieve hemostasis, but percutaneous N-butyl cyanoacrylate glue seal-off was performed successfully. Percutaneous resurrection of mummy vascular access sites for hemodialysis is technically feasible with high clinical success rates. In selected patients, resurrection of mummy access sites provides long-discarded access sites one more chance to be used for hemodialysis in an effort to preserve potential extremity sites for future access-site placement and to prevent long-term catheter indwelling.

The purpose of this paper is to describe a unique "eighth note" deformity of the autogenous radiocephalic fistula for hemodialysis and to retrospectively evaluate the efficacy and safety of its endovascular treatment. Over 3 years, a total of 808 patients and 558 autogenous radiocephalic fistulas were treated for vascular access dysfunction or thrombosis. These included 14 fistulas in 14 patients (9 men, 5 women; mean age, 58.2 +/- 2.8 years; range 27-79 years) whose fistulograms before treatment resembled a musical note, the eighth note. Endovascular treatment sought to remodel the deformed vascular access to a classic radiocephalic fistula and increase the number of cannulation sites available for hemodialysis. The technical and clinical success rates were each 92.8% (13/14). Fistula remodeling was successful in 13 patients. The postintervention primary patency was 100% at 90 days, 91.7 +/- 0.8% at 120 days, 78.6 +/- 13.9% at 180 days, 62.9 +/- 17.9% at 360 days, 31.4 +/- 24.0% at 540 days, and 0% at 720 days. The postintervention secondary patency was 100% at 90 days, 100% at 120 days, 100% at 180 days, 85.7 +/- 13.2% at 360 days, and 85.7 +/- 13.2% at 720 days. No major complications were noted. Minor complications were found in 71.4% of patients, all of which resolved spontaneously. In conclusion, endovascular treatment of fistulas with the eighth note deformity can effectively increase the number of available cannulation sites, facilitate fistula maturation, and facilitate thromboaspiration after fistula thrombosis.

Objective: We wanted to report our experience of metallic stent placement after insufficient balloon dilation in graft hemodialysis patients., Materials and Methods: Twenty-three patients (13 loop grafts in the forearm and 10 straight grafts in the upper arm) underwent metallic stent placement due to insufficient flow after urokinase thrombolysis and balloon dilation. The indications for metallic stent deployment included 1) recoil and/or kinked venous stenosis in 21 patients (venous anastomosis: 17 patients, peripheral outflow vein: four patients); and 2) major vascular rupture in two patients. Metallic stents 8-10 mm in diameter and 40-80 mm in length were used. Of them, eight stents were deployed across the elbow crease. Access patency was determined by clinical follow-up and the overall rates were calculated by Kaplan-Meier survival analysis., Results: No procedure-related complications (stent fracture or central migration) were encountered except for a delayed Wallstent shortening/migration at the venous anastomosis, which resulted in early access failure. The overall primary and secondary patency rates (+/-standard error) of all the vascular accesses in our 23 patients at 3, 6, 12 and 24 months were 69%+/-9 and 88%+/-6, 41%+/-10 and 88%+/-6, 30%+/-10 and 77%+/-10, and 12%+/-8 and 61%+/-13, respectively. For the forearm and upper-arm grafts, the primary and secondary patency rates were 51%+/-16 and 86%+/-13 vs 45%+/-15 and 73%+/-13 at 6 months, and 25%+/-15 and 71%+/-17 vs 23%+/-17 and 73%+/-13 at 12 months (p = .346 and .224), respectively., Conclusion: Metallic stent placement is a safe and effective means for treating peripheral venous lesions in dialysis graft patients after insufficient balloon dilation. No statistically difference in the patency rates between the forearm and upper-arm patient groups was seen.

Objective: The purpose of this study was to report our experience with metallic stent placement in the peripheral outflow veins in native arteriovenous fistula (A-V fistula) hemodialysis patients after insufficient balloon dilatation., Materials and Methods: During the past 4 years, 12 A-V fistula dialysis patients in our hospital underwent metallic stent placement in the peripheral outflow veins to restore vascular access. The indications for metallic stent placement in our study included (1) recoil stenosis of outflow vein in six patients; (2) outflow venous rupture in two patients and dissection in one patient; and (3) large residual adherent thrombus in outflow aneurysms in three patients with thrombosed (arteriovenous) access. Self-expandable Wallstent or Jostent (Jomed, Abbott Laboratories) of appropriate size (6-10 mm in diameter) was chosen for use in these patients. Kaplan-Meier survival analysis was used to calculate the access patency rates., Results: Twelve patients received stents. Eleven patients (92%) underwent successful dialysis after the procedure. One patient experienced complications due to incorrect positioning of the stent at the anastomotic site, causing flow compromise. The primary patency (+/- standard error) of the vascular access at 3, 6, 12, and 24 months was 92% +/- 8%, 81% +/- 12%, 31% +/- 17%, and 31% +/- 17%, respectively. The secondary patency of the vascular access at 3 months was 92% +/- 8%, and 82% +/- 12% at 6, 12, and 24 months each., Conclusion: Metallic stent placement is safe and effective in treating peripheral venous lesions in native A-V fistula hemodialysis patients after unsatisfactory balloon dilatation.

Purpose: To evaluate the authors' experience with a technique for management of thrombosed Brescia-Cimino arteriovenous fistula., Materials and Methods: Forty patients with 42 thrombosed arteriovenous fistulas were percutaneously treated. Thrombosis occurred within 24 hours of attempted angioplasty in five fistulas, between 24 and 72 hours in 27, and longer than 72 hours in 10. Thrombosed fistulas were approached in a retrograde fashion followed by direct balloon dilation with 5-8-mm balloon catheters. If retrograde catheterization failed to cross the arterial anastomosis, an antegrade puncture directly into the thrombosed drainage vein close to the anastomosis was performed with ultrasonographic guidance, as an aid to catheterize the arterial inflow. Thrombolytic therapy with infusion of urokinase directly into the thrombus was performed in selected patients with visible thrombus that had compromised blood flow in the partially restored vascular access. Postintervention primary and secondary patency was calculated by using Kaplan-Meier analysis. Patency rates between patients without and with urokinase infusion were examined by using the log-rank test., Results: Anatomic success was achieved in 39 (93%) of 42 fistulas; and clinical patency, in 38 (90%) of 42 fistulas. Postintervention primary and secondary patencies (including initial technical failure) at 6, 12, and 18 months were 81% and 84%, 70% and 80%, and 63% and 80%, respectively. No significance of patency rate between patients without and with urokinase infusion was found (P =.912). Three patients died of unrelated causes at 1, 2, and 5 months after the procedures. No major complications were encountered., Conclusion: High anatomic success and excellent clinical patency can be achieved in the salvage of thrombosed arteriovenous fistulas. Percutaneous restoration of arteriovenous fistulas should be attempted before surgical recreation to optimize outcome in patients undergoing hemodialysis., (Copyright RSNA, 2002)