Assisted Primary Patency Rates Research Articles

Retrospective evaluation of three types of expanded polytetrafluoroethylene grafts for upper limb vascular access

Currently, three expanded polytetrafluoroethylene (ePTFE) prosthetic graft types are most commonly used for patients with end-stage kidney disease (ESKD) who require long-term vascular access for hemodialysis. However, studies comparing the three ePTFE grafts are limited. This study compared the clinical efficacy and postoperative complications of three ePTFE prosthetic graft types used for upper limb arteriovenous graft (AVG) surgery among patients with ESKD. Patients with ESKD requiring upper limb AVG surgery admitted to our center between January 2016 and September 2019 were enrolled. Overall, 282 patients who completed the 2-year follow-up were included and classified into the following three groups according to the ePTFE graft type: the GPVG group with the PROPATEN® graft, the GAVG group with the straight-type GORE® ACUSEAL, and the BVVG group with the VENAFLO® II. The patency rate and incidence of access-related complications were analyzed and compared between groups. The patients were followed up postoperatively, and data were collected at 6, 12, 18, and 24 months postoperatively. Respective to these follow-up time points, in the GPVG group, the primary patency rates were 74.29%, 65.71%, 51.43%, and 42.86%; the assisted primary patency rates were 85.71%, 74.29%, 60.00%, and 48.57%; and the secondary patency rates were 85.71%, 80.00%, 71.43%, and 60.00%. In the GAVG group, the primary patency rates were 73.03%, 53.93%, 59.42%, and 38.20%; the assisted primary patency rates were 83.15%, 68.54%, 59.55%, and 53.93%; and the secondary patency rates were 85.39%, 77.53%, 68.54%, and 62.92%, respectively. In the BVVG group, the primary patency rates were 67.24%, 53.45%, 41.38%, and 29.31%; the assisted primary patency rates were 84.48%, 67.24%, 55.17%, and 44.83%; and the secondary patency rates were 86.21%, 81.03%, 68.97%, and 60.34%, respectively. The differences in patency rates across the three grafts were not statistically significant. Overall, 18, 4, and 12 patients in the GPVG, GAVG, and BVVG groups, respectively, experienced seroma. Among the three grafts, GORE® ACUSEAL had the shortest anastomosis hemostatic time. The first cannulation times for the three grafts were GPVG at 16 (±8.2), GAVG at 4 (±4.9), and BVVG at 18 (±12.7) days. No significant difference was found in the postoperative swelling rate between the GPVG group and the other two groups. Furthermore, no statistically significant differences were found across the three graft types regarding postoperative vascular access stenosis and thrombosis, ischemic steal syndrome, pseudoaneurysm, or infection. In conclusion, no statistically significant differences in the postoperative primary, assisted primary, or secondary graft patency rates were observed among the three groups. A shorter anastomosis hemostatic time, first cannulation time, and seroma occurrence were observed with the ACUSEAL® graft than with its counterparts. The incidence of upper extremity swelling postoperatively was greater with the PROPATEN® graft than with the other grafts. No statistically significant differences were observed among the three grafts regarding the remaining complications.

Femoral vein translocation for complex hemodialysis access

ObjectiveVascular access is difficult in patients without suitable arm veins and prior graft infections. The use of femoral vein translocation (FVT) to the upper extremity or contralateral lower extremity for hemodialysis access may be associated with low infection rates and high patency rates. FVT is used for patients without central venous occlusion who have failed prior access either owing to graft infection or repetitive graft thrombosis. The largest case series consists of 30 cases. The objective of this study is to determine the infection incidence, primary patency, primary-assisted patency, and secondary patency rates among FVTs. MethodsA retrospective chart review was performed on all patients who underwent FVT by a single vascular practice over a 10-year period (2013-2023). Study variables included length to last follow-up (months), prior access, prior graft infection, comorbid conditions, primary patency, primary-assisted patency, secondary patency, postoperative steal syndrome, postoperative graft infection, postoperative harvest site complication, and postoperative lower extremity compartment syndrome. ResultsA total of 131 FVTs were performed from 2013 to 2023; 126 patients (47% male, 53% female; 76% Black, 24% White) with a mean age of 52 ± 14 years and a mean body mass index of 29 ± 8 had at least 1 month of follow-up and were included for analysis. The median follow-up was 46 months (interqurtile range, 19-72 months). The mean number of prior permanent accesses was 2.5 ± 1.4. Forty-eight percent of patients had prior graft infections. The primary, primary-assisted, and secondary patency rates were 66%, 93%, and 98%, respectively, at 6 months; 43%, 85%, and 96% at 12 months; 25%, 70%, and 92% at 24 months; 16%, 61%, and 88% at 36 months; and 14%, 56%, and 82% at 48 months. Postoperative steal syndrome and postoperative access infection requiring excision was observed 16% and 5% of patients, respectively. Harvest site complications requiring an additional procedure occurred in 19% of cases. Three patients developed lower extremity compartment syndrome postoperatively, requiring fasciotomy. Six patients developed chronic lower extremity edema after femoral vein harvest. The mean procedure time and hospital length of stay were 197 ± 40 minutes and 3.5 ± 2.8 days, respectively. ConclusionsFVT is associated with low infection rates and high long-term patency rates. Significant postoperative complications include steal syndrome and harvest site complications. FVT remains a viable option for patients who have failed prior access owing to graft infection or repetitive graft thrombosis.

Combination of BeGraft and Solaris Stent Grafts for the Covered Endovascular Reconstruction of Aortic Bifurcation-BS-CERAB Technique.

Background: This study examines the impact of the use of the combination of BeGraft and Solaris stent grafts on the outcomes during the covered endovascular reconstruction of aortic bifurcation (BS-CERAB) technique and extension to the iliac arteries. Methods: Consecutive patients with aortoiliac occlusive disease who underwent endovascular treatment using BS-CERAB between January 2020 and December 2023 were included. Patient demographics, symptoms, lesion characteristics, and procedural and follow-up details were collected and analyzed. Perioperative complications and reinterventions were also identified. Results: A total of 42 patients met the inclusion criteria (32 men, 76.2%, median age 72 years, range 59-85). Indications for treatment were intermittent claudication (42.9%) and critical limb ischemia (57.1%). Procedure success was achieved in all cases. The median patient follow-up time was 14 months (1-36). One patient died at a 10-month follow-up due to lung cancer. The mean pre-operative ABI increased from 0.37 ± 0.19 before intervention to 0.71 ± 1.23 post-operatively at 12 months (p = 0.037). The estimated primary patency rates at 3, 6, and 12 months were 90.5%, 85.7%, and 81.0% and primary assisted patency rates were 90.5%, 90.5%, and 85.7%, respectively. Secondary patency was 95.2% at 3 and 6 months and 90.5% at a 12-month follow-up. Active cancer (p = 0.023, OR 2.12 95%CI 1.14-3.25) was a risk factor for restenosis. Conclusions: This mid-term experience shows that the CERAB technique using the combination of BeGraft and Solaris stents grafts, for the endovascular treatment of severe aortoiliac atherosclerotic disease, may allow an effective reconstruction of the aortic bifurcation and iliac arteries related to high-patency and lower-reintervention rates.

Mid-term Results of Endovascular Reconstruction of Aortic Bifurcation Using COVERA Stent Graft.

This article aims to evaluate the short-term and mid-term performance of a self-expanding covered stent (COVERA Plus, Bard Tempe, Arizona) during the treatment of Trans-Atlantic Inter-Society Consensus (TASC) C/D aortoiliac obstructive lesions involving the aortic bifurcation. A single-center retrospective review of all patients who underwent endovascular reconstruction of the aortoiliac bifurcation for obstructive disease, with the use of Covera, from January 2018 to March 2023. All patients received a postoperative CTA (computed tomography angiography) scan within 1 month from the intervention. Precision of deployment, stent conformation, and stent symmetry were evaluated at the arterial phase of the CTA. Early outcomes were technical success and freedom from open aortic reintervention and/or mortality. Late outcomes were primary and assisted primary patency rates and freedom from reintervention. During the study period, 35 patients underwent primary endovascular treatment of obstructive lesions involving the aortic bifurcation with parallel COVERA stents. Aortoiliac lesions were classified as TASC-IIC in 23 (65.7%) patients and TASC D in 12 (34.2%). Median follow-up was 49 months (interquartile [IQR]: 18-60). Overall survival was 97.1% (95% confidence interval [CI]=91-100) at 60 months. During follow-up, there were one early stent stenosis, treated with an angioplasty and stent relining with an estimated primary patency at 60 months of 97.1% (95% CI=94-100) and a primary-assisted patency of 100%. Estimated freedom from all types of reinterventions at 60 months was 94.3% (95% CI=89-99.3). The new self-expanding covered Bard COVERA Plus stent used for endovascular treatment of TASC C/D aorto iliac disease proved to be safe and feasible with high technical procedural success rates. Comparison with other types of stents is necessary to further assess the role of the COVERA Plus stent in aortic bifurcation repair. This study investigates the safety and feasibility of the new self-expanding covered Bard Covera Plus stent used for endovascular treatment of TASC C/D aorto iliac disease. The retrospective analysis of 35 patients highlights high technical success and primary patency rate at 60 months. The geometric analysis also helped to underline how this stent can be used precisely in particular conditions. These findings suggest the need for further research to compare COVERA with other types of stents in aortic bifurcation repair.

Small Oversized Stent Graft Is Associated With Increased Patency for the Treatment of Central Venous Disease in Hemodialysis Patients.

The purpose of this study was to identify the independent predictors of higher patency rates and investigate the selection of specifications of stent graft in the treatment of central venous disease. This retrospective study included 54 patients who underwent stent-grafts' placement for the treatment of central venous disease between March 2017 and September 2022 at a tertiary hospital. The demographic data for the patients and the clinical data of the treated lesions were collected and analyzed. The patency rates of the treated lesions with different oversizing range were calculated via the Kaplan-Meier and log-rank analyses. The multivariate Cox proportional hazard models were constructed to identify the independent predictor of the target site primary patency. The median follow-up period was 21.5 months. The primary patency rates of the target sites were 90.7%, 72.2%, and 55.1% at 6, 12, and 24 months, respectively. The assisted primary patency rates of the lesions were 96.3%, 92.5%, and 80.3% at 6, 12, and 24 months, respectively. The log-rank analysis showed that the stent-grafts' placement with small oversizing had significantly higher primary patency rates than those with large oversizing (p=0.022). The multivariate analysis revealed that concomitant stenosis and large oversizing stent graft were the independent predictors of target site primary patency. Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing. Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. Few studies, however, have explored the efficiency of stent grafts to treat CVD by considering different factors such as sizing considerations, the rate of oversizing percentage, etc. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing. Excessive oversizing should be avoided to prevent infolding or stent collapse.

Percutaneous Transluminal Angioplasty (PTA) and Stent Implantation in Hemodialysis Patients with Central Venous Stenosis:A Study of Outcomes

BACKGROUND: Central venous stenosis and occlusion are serious complications that can arise from central venous catheterization in hemodialysis patients, leading to significant difficulties in the dialysis process. Common clinical manifestations include swelling in the arm or neck on the affected side and compromised hemodialysis access. To address this issue, percutaneous balloon angioplasty and stent implantation have emerged as potential solutions to maintain vein patency. However, there is a need to evaluate the efficacy of these interventions over an extended period to determine their long-term benefits. This study aimed to monitor the patency status periodically, starting at 1st Month, followed by assessments at 3rd Month, 6th Month, and finally, the 12th Month. METHODS: This single-center observational study focused on endovascular interventions performed on hemodialysis patients with central venous stenosis or occlusion.Participants included end-stage renal failure patients undergoing hemodialysis who exhibited clinical signs of central venous stenosis or occlusion. Data were collected from 60 patients, consisting of 42 males (70%) and 18 females (30%), with an average age of 46.19±13.21 years. The affected sites of central vein stenosis or occlusion were distributed as follows: 13 cases in the innominate veins, 25 cases in the superior vena cava, 18 cases in the brachiocephalic vein, and 10 cases in the subclavian vein. Some patients had multiple site occlusions, while others experienced occlusion of AV fistula. RESULTS: Of the 60 endovascular procedures performed, only one case did not achieve technical success, resulting in an overall success rate of 96.4%. Stent implantation was carried out in only four patients. No significant procedure-related complications were encountered, and all patients were able to undergo hemodialysis after the initial intervention. The primary patency rates for PTA at 1, 3, 6, and 12 months were 96%, 92%, 88%, and 86%, respectively. As for stent implantation, the primary patency rates at 1, 3, 6, and 12 months were 100%, 98%, 98%, and 98%, respectively. Assisted primary patency rates for PTA at 1, 3, 6, and 12 months were 2%, 6%, 11%, and 14%, respectively. During the 12-month follow-up, 10 reinterventions were performed, with three patients requiring more than two reinterventions. CONCLUSION: The study's findings demonstrate that endovascular interventions, such as percutaneous balloon angioplasty and stent implantation, are highly effective in managing central venous stenosis or occlusion in hemodialysis patients. These interventions showed a remarkable success rate and a minimal occurrence of procedure-related complications. Particularly, stent implantation consistently exhibited 100% primary patency at all evaluated time points. While the assisted primary patency rates for PTA were relatively lower, the overall need for reinterventions remained low, emphasizing the long-term benefits of these procedures. Based on these promising results, endovascular interventions can be considered as a viable and efficient option for the management of central venous stenosis or occlusion in hemodialysis patients, offering improved hemodialysis access and ensuring enhanced patient outcomes.

Dual outflow upper arm arteriovenous fistula: An effective technique to prevent cephalic arch stenosis.

Cephalic arch stenosis (CAS) is critical point to maintain functional arteriovenous fistula (AVF) in patients undergoing hemodialysis with brachio-cephalic AVFs. In this study, we aimed to determine the effectiveness of dual outflow (cephalic and basilic veins) as a surgical method to prevent CAS. Between July 2016 and December 2019, 369 patients underwent upper arm AVF creation. Among them the 251 patients were enrolled in this retrospective study. Two hundred seven underwent brachio-cephalic arteriovenous fistula (BCAVF) and 44 underwent brachio-cephalicbasilic arteriovenous fistula (BCBAVF). From the 251 patients, diabetes mellitus (66.7% vs 36.4%, P < .001) and hypertension (91.3% vs 75%, P = .002) were more common in the patient group who underwent BCAVF surgery; however, the difference in volume flow to the fistula did not differ between the 2 groups. CAS (30.4% vs 9.1%, P = .004) and fistula occlusion (15.9% vs 4.5%, P = .048) were likely to occur in the BCAVF group. The primary patency rates at 12 months were 74.3% and 86.4% for the BCAVFs and BCBAVFs, respectively (P = .075). The primary-assisted patency rates at 12 months were 87.0% for BCAVFs and 93.2% for BCBAVFs, respectively (P = .145). Secondary patency rates at 12 months were 92.2% for BCAVFs and 93.2% for BCBAVFs, respectively (P = .023). Compared to BCAVF, traditional upper arm AVF, upper arm AVF with cephalic and basilic vein dual drainage can be optimal surgical method to preventing CAS.

AFX unibody stent graft: Effective and safe for the treatment of severe aorto-iliac occlusive disease.

The primary objective of this study was to determine the primary, assisted primary and secondary patency rates of the Endologix AFX stent-graft in patients considered high risk for open surgery with complex aorto-iliac occlusive disease. The secondary objective was to determine 30-day major adverse cardiovascular and cerebrovascular events. A retrospective review was undertaken of clinical records of 38 patients who underwent AFX stent-graft placement for aorto-iliac occlusive disease from 2016 to 2019. Patient data was de-identified and entered into a REDcap secure database. Descriptive statistical analysis (means and standard deviations) and Kaplan-Meier survival curves were created to determine the duration of patency of the AFX stent-graft system. Primary patency rates at 6, 12 and 24months were 92%, 92% and 84%, respectively. Assisted primary patency rates at these times were 100%, 100% and 93% with secondary patency of 100% maintained throughout. The incidence of 30-day major adverse cardiovascular and cerebrovascular events was 8% and major adverse limb events was 3%. One death unrelated to the AFX device occurred during the study period though outside of the 30-day peri-operative period. Primary, assisted primary and secondary patency rates of AFX stent-grafts, when used to treat aorto-iliac occlusive disease, are high. This study supports the use of the AFX stent-graft for the endovascular treatment of complex aorto-iliac occlusive disease as an alternative to other endovascular options as well as a safe alternative to open aorto-iliac or aorto-femoral bypass in patients who are at high risk for open procedures.

Comparison of Lower and Upper Extremity Arteriovenous Graft: A Retrospective Clinical Analysis with 5-Year Follow-Up

For patients in whom an upper extremity (UE) vascular access cannot be established, the lower extremity (LE) arteriovenous graft (AVG) could be selected. However, the application of LE AVG is limited owing to its high infection rate, uncertain patency time, and technical difficulties. This study aimed to compare the long-term patency rates and the incidence of vascular access complications of AVG in the LE and UE to provide a reference for the applications of AVG, especially in the LEs. This was a retrospective analysis of patients who successfully underwent LE or UE AVG placement from March 2016 to October 2021. Patient characteristics were collected and compared using parameter or nonparameter tests according to data type. Postoperative patency was evaluated using Kaplan-Meier test. Postoperative complication incidence density and intergroup comparison were estimated using the Poisson distribution. Twenty-two patients with LE AVG and 120 patients with UE AVG were included. The 1-year primary patency rate was 67.4% (±11.0% standard error [SE]) in the LE group and 30.1% (±4.5% SE) in the UE group (P=0.031). The assisted primary patency rate at postoperative months 12, 24, and 36 was respectively 78.6% (±9.6% SE), 65.5% (±14.4% SE), and 49.1% (±17.8% SE) in the LE group and 63.3% (±4.6% SE), 47.5% (±5.4% SE), and 30.4% (±6.1% SE) in the UE group (P=0.137). The secondary patency rate at postoperative months 12, 24, and 36 remains 95.5% (±4.4% SE) in the LE group and 89.3% (±2.9% SE), 83.7% (±3.9% SE), and 73.0% (±6.2% SE), respectively, in the UE group (P=0.200). Postoperative complications included stenosis, occlusion/thrombosis, infection, steal syndrome, pseudoaneurysm, severe postoperative serum swelling, and AVG exposure. The total incidence rates of postoperative complications were 0.87 (95% confidence interval [CI] 0.59-1.23) versus 1.61 (95% CI 1.45-1.79) (P=0.001) cases/person-year, the incidence rates of stenosis were 0.45 (95% CI 0.26-0.73) versus 0.92 (95% CI 0.80-1.06) (P=0.005) cases/person-year and the incidence rates of occlusion/thrombosis were 0.34 (95% CI 0.17-0.59) versus 0.62 (95% CI 0.52-0.74) cases/person-year in the LE group compared to those in the UE group (P=0.041). LE AVG had higher primary patency rate and lower postoperative complication incidence than UE AVG. With the development of interventional technology, both LE AVG and UE AVG exhibited high secondary patency rates. LE AVG can be a reliable and long-term alternative for appropriately selected patients with unusable UE vessels.

Is the Mid-Term Patency Rate of Small-Diameter Viabahn Stent-Grafts in Peripheral Artery Disease Related to Their Length? A Systematic Review.

Small-diameter endografts can be used for the treatment of the peripheral vascular disease, but the patency rate during the follow-up is still under debate. With this review, we aimed at analyzing the mid-term patency of small-diameter Viabahn stent-grafts and investigating the relationship between patency and the length of the graft. We performed a review of articles published until September 2020 and reporting use of ≤7-mm-diameter Viabahn stent-grafts in diseased peripheral arteries. Data on study type, demographic, lesion length, stent-graft diameter, length, and patency (1-year, 3-year, 5-year primary patency, primary-assisted patency, and secondary patency), follow-up, endoleak, and re-intervention rates were extracted and analyzed. A statistical test was applied to identify a correlation between stent-graft length and patency. 16 retrospective and 7 prospective studies reported the outcome of 1613 patients (mean age: 69.6±33.7 years). There was considerable heterogeneity in reporting standards among studies. The diameter of Viabahn stent-grafts ranged 5 to 7mm and the average length was 23.6±12.4cm. Heparin-bonded grafts were used in 46.4% of cases. Mean follow-up time was 26.4±17.6 months. The 1- and 5-year primary patency rate was 75.7% (95% CI, 73.6%-77.8%) and 46.8% (95% CI, 41.0%-52.6%), respectively. The 1- and 5-year primary-assisted patency rate was 80.9% (95% CI, 73.9%-87.8%) and 60.9% (95% CI, 46.4-75.5%), respectively. The 1- and 5-year second-assisted patency was 90.4% (95% CI, 87.4%-93.3%) and 73.7% (95% CI, 64.7%-82.8%), respectively. No correlation between the stent-graft length and patency was found. Small-diameter Viabahn stent-graft implantation represents a safe treatment for patients with peripheral artery disease, and the mid-term patency rate seems not be affected by the length of the graft. The use of small diameter stent-grafts for peripheral vascular disease is an established technique but the patency rate is still under debate. With this review we have investigated the relationship between the mid-term patency and the diameter of the stent-grafts. Afterv having analysed data from 23 published studies including 1613 patients we can conclude that the treatment of the peripheral artery disease with small diameter stent-grafts is safe and the mid-term patency rate seems not be affected by the lenght of the grafts.

Factors associated with difficulty in stenting the chronic iliofemoral venous obstruction.

The main aim of this article is to investigate the causes of technical failure during endovascular recanalization in patients with post-thrombotic syndrome with occluded iliofemoral veins and to suggest alternative techniques to improve outcomes in such challenging cases. Between November 2015 and August 2020, 230 patients (274 limbs) treated in our institution with symptomatic chronic iliofemoral venous obstruction underwent endovascular recanalization with angioplasty and stent placement. Overall, the initial attempt was unsuccessful in 15 limbs. We retrospectively analyzed the basic demographic and health characteristics of the involved patients and evaluated the endovascular procedures and techniques that resulted in a successful second intervention. The first attempts at endovascular intervention were unsuccessful in 15 of the 274 limbs (5.4%). Failures were attributed to hostile groin areas in intravenous drug abusers caused by multiple punctures in six cases. In addition, five interventions failed due to prior surgery at the site of venous occlusion and in retroperitoneal space, three patients due to severe stent deformity, and one patient due to congenital venous aplasia. Of the 15 patients, 11 underwent a subsequent attempt that included six successful recanalizations. The mean follow-up time of the six patients with successful recanalization was 27 months (5-62 months). The primary, assisted primary and secondary patency rates were 83.3%, 100%, and 100%, respectively. The remaining five patients, in whom the second recanalization attempt failed, received conservative treatment. Recanalization failure is rare in chronic venous obstruction patients. Severe stent deformities have the lowest chance of successful second intervention. Patients with a hostile groin or prior open surgeries at the occlusion site may be considered for reintervention with a success rate of nearly 50%.

Comparison between Kissing Stents and Direct Surgical Bypass for Aortoiliac Occlusive Disease.

The optimal management strategy for aortoiliac occlusive disease (AIOD) remains debatable. This study compared early and late outcomes between direct surgical bypass and kissing stents for AIOD treatment. We retrospectively reviewed data, including age, sex, risk factors, comorbidities, symptoms, TransAtlantic Inter-Society Consensus (TASC) II classification, operation time, perioperative complications, in-hospital mortality, and length of hospital stay, from a cohort of 46 patients treated for AIOD (24 with kissing stents and 22 with direct surgical bypass) at Pusan National University Hostpital from January 2007 to December 2016. The primary, assisted primary, and secondary patency rates in both groups were compared. The hospital stay (direct surgical bypass vs. kissing stents: 16.36±5.19 days vs. 9.08±10.88 days, p=0.007) and operation time (direct surgical bypass vs. kissing stents: 316.09±141.78 minutes vs. 99.54±37.95 minutes, p<0.001) were significantly shorter for kissing stents. Kaplan-Meier analysis revealed that the primary, assisted primary, and secondary patency rates in the direct surgical bypass group were 95.5%, 95.5%, and 95.5%, respectively, at 1 year; 86.4%, 86.4%, and 95.5% at 3 years; and 77.3%, 77.3%, and 95.5% at 5 years. The primary, assisted primary, and secondary patency rates in the kissing stent group were 100.0%, 100.0%, and 100.0%, respectively, at 1 year; 95.8%, 95.8%, and 100.0% at 3 years; and 95.8%, 95.8%, and 100.0% at 5 years. Except for special cases wherein endovascular revascularization is difficult, kissing stents are more advantageous for TASC II C and D lesions.

Outflow Rescue of Elbow-Blockade Forearm Arteriovenous Fistulas: Outcomes of Open Surgical Techniques

Venous scarring at the elbow is a common problem that can cause early and late forearm arteriovenous fistula (AVF) dysfunction in hemodialysis patients. However, any effort to prolong the long-term patency of distal vascular accesses could benefit the patient's survival, maximizing the use of restricted venous patrimony. This study aims to report a single-center experience in the recovery of distal autologous AVF with venous outflow obstruction at the elbow using different surgical techniques. Retrospective observational study of all patients treated at a single vascular access center from January 2011 to March 2022, with dysfunctional forearm AVFs presenting with outflow stenosis or occlusions at the elbow treated by open surgery, using 3 different surgical techniques. Demographics and clinically relevant data were collected. Evaluated endpoints included primary, assisted primary, and secondary patency rates at 1 and 2years. Twenty-three patients with elbow-blocked outflow forearm AVFs have been treated with a mean age of 64±15years. The majority (96%) had a radiocephalic fistula. The median time from vascular access creation to intervention was 34.5months (12-216months). A total of 24 procedures have been performed using 3 different surgical techniques for bypassing the obstructed venous outflow at the elbow. Technical success was achieved in 96% of the surgically treated patients. Primary and secondary patency rates at 1year were 67.4% and 89.4%, respectively, and 52.9% and 82.0% at 2years, with a median follow-up of 19months (6-92months). AVFs outflow stenosis or occlusions at the elbow not amenable to endovascular therapy could lead to vascular access abandonment. Our study demonstrates multiple surgical solutions to avoid this adverse outcome. Elbow venous outflow surgical reconstruction seems effective for distal vascular access preservation. Close surveillance is essential for timely endovascular treatment of newly developed stenosis at the venous drainage.

Duplex-Guided Ipsilateral Antegrade Approach for Flush Superficial Femoral Artery Occlusion.

Recanalization of flush ostial superficial femoral artery (SFA) occlusion is a very challenging procedure. Using the ipsilateral antegrade approach in such lesions has some difficulties. This study aimed to assess the feasibility, efficacy, and outcomes of duplex-guided ipsilateral antegrade access for endovascular treatment of atherosclerotic flush occlusion of the SFA. This is a prospective two-center study that included chronic lower extremity ischemia patients with flush occlusion of SFA who underwent duplex-guided ipsilateral antegrade endovascular revascularization due to unfeasible contralateral femoral approach. Flush occlusions were preoperatively documented by duplex ultrasound and computed tomography angiography in all patients. The outcome measures were technical success, patency rates, perioperative morbidity and mortality, limb salvage, and amputation free survival rates. Between April 2019 and March 2021, 49 patients were enrolled in the current study with a mean age of 63.7 ± 5.7years. Diabetes was the most common risk factor and was found in 40 (81.6%) patients. Associated popliteal lesions were found in seven (14.3%) patients, while 10 (20.4%) patients had combined tibial disease. Selective stenting was done in nine (18.4%) patients. Technical success was achieved in 43 (87.8%) patients. All failures were due to inability to cross the lesion rather than failure to access the common femoral artery. All complications were minor and occurred in seven (14.3%) patients. Primary, assisted primary, and secondary patency rates were 63.9% ± 7.1%, 82.8% ± 5.6%, and 93.5% ± 3.7% at 12months, respectively. The overall 12-month limb salvage and amputation free survival rates were 91.8% and 83.3% ± 5.4%, respectively. Duplex-guided ipsilateral antegrade femoral access is a feasible, safe, and effective endovascular treatment option for flush SFA occlusion when contralateral femoral access is not possible.

A Retrospective Review of Bovine Artery Graft Patency: A Single-Site Study

The hemodialysis-dependent population is increasing in the United States. Dialysis access complications are a significant source of morbidity and mortality for patients with end-stage renal disease. A surgically created autogenous arteriovenous fistula has been the gold standard for dialysis access. However, for patients who are not candidates for arteriovenous fistula, arteriovenous grafts using various conduits have widely been used. In this study, we report the outcomes of bovine carotid artery (BCA) grafts for dialysis access at a single institution and compare these results to those for polytetrafluoroethylene (PTFE) grafts. A single-institution, retrospective review of all patients undergoing surgical placement of a bovine carotid artery graft for dialysis access from 2017-2018 was performed under an institutional review board-approved protocol. The primary, primary-assisted, and secondary patency were calculated for the whole cohort and results determined based on gender, body mass index (BMI), and indication for use. Comparison was performed to PTFE grafts at same institution from 2013 to2016. One hundred and twenty two patients were included in this study. Seventy four patients had a BCA graft placed while 48 had a PTFE graft placed. . The mean age was 59.7±13.5years in the BCA group, 55.8±14.5 in the PTFE group, and the mean BMI was 29.8±9.2kg/m2 in the BCA group and 28.1±9.7 in the PTFE group. Comparison of the comorbidities present in BCA/PTFE groups included hypertension (92%/100%), diabetes (57%/54%), congestive heart failure (28%/10%), lupus (5%/7%), and chronic obstructive pulmonary disease (4%/8%). The various configurations were reviewed (BCA/PTFE): interposition/access salvage (40.5%/13%), axillary-axillary (18.9%, 7%), brachial-basilic (5.4%, 6%), brachial-brachial (4.1%, 4%), brachial-cephalic (1.4%, 0%), axillary-brachial (1.4%, 0%), brachial-axillary (23%, 62%), and femoral-femoral (5.4%, 6%). Overall, 12-month primary patency was 50% in the BCA group and 18% in the PTFE group (P=0.001). Twelve-month primary-assisted patency was 66% in the BCA group and 37% in the PTFE group (P=0.003). Twelve-month secondary patency was 81% in the BCA group and 36% in the PTFE group (P=0.07). When comparing BCA graft survival probability among male and female gender, males had better primary-assisted patency (P=0.042). Secondary patency among the 2 genders was similar. There was no statistically significant difference in primary, primary-assisted, and secondary patency of BCA grafts between different BMI groups and indication for use. The average patency of a bovine graft was 17.8±8months. Sixty one percent of the BCA grafts needed intervention with 24% needing multiple interventions. There was an average of 7±5months to first intervention. The infection rate was 8.1% in the BCA group and 10.4% in the PTFE group with no statistical difference. Primary and primary-assisted patency rates at 12months in our study were higher than those for PTFE at our institution. There was higher primary-assisted patency of BCA grafts among males at 12months compared to PTFE. Obesity and indication for BCA graft use did not appear to affect patency in our population.

The efficacy of stenting in the iliofemoral vein of patients with venous obstruction and secondary lymphedema from malignancy

ObjectiveTo investigate the safety and effectiveness of venous stenting in patients with chronic iliofemoral venous obstruction and secondary lymphedema from malignancy. MethodsFrom July 2012 to December 2020, patients with iliofemoral venous obstruction and secondary lymphedema who underwent venous stenting in our institution were reviewed retrospectively. Clinical characteristics, surgical complications, and symptom relief were assessed. Stent patency was evaluated with duplex ultrasound or computed tomographic venography. Twelve-month outcomes were reported. ResultsFifty-three patients with concurrent secondary lymphedema who had stents placed for iliofemoral venous obstruction were included. There were 42 females, and the mean age was 56.9 years. Nonthrombotic iliac vein lesions were identified in 16 patients (30.1%). Immediate technical success was 100%, with an average of two stents implanted. The median Villalta score, and Chronic Venous Disease Quality of Life quality of life questionnaire scores decreased from 12 (IQR, 10-15) and 58 (IQR, 50-66) at baseline, respectively, to 5 (interquartile range [IQR], 4-6) and 28 (IQR, 22-45) at 12 months after the procedure (P < .05), showing significant improvement in the quality of life. At the end of a median follow-up of 12 months (range, 3-25 months), the cumulative primary, assisted primary, and secondary patency rates were 70.8%, 76.9%, and 90.1%, respectively. ConclusionsIn patients with secondary lymphedema from malignancy, venous stent placement is safe and effective for iliofemoral venous obstruction.

Outcome and Risk Factors of Restenosis Post Percutaneous Transluminal Angioplasty at Juxta-Anastomotic of Wrist Autogenous Radial-Cephalic Arteriovenous Fistulas: A Retrospective Cohort Study

This retrospective cohort study was to determine the factors related to restenosis post percutaneous transluminal angioplasty (PTA) at juxta-anastomotic of wrist radial-cephalic arteriovenous fistulas (RC-AVFs). We conducted a retrospective study of patients who underwent their first PTA for juxta-anastomotic stenosis at RC-AVF from January 1, 2016, to December 31, 2020. Patient and stenotic lesion characteristics and PTA procedure factors were included in the analysis. The primary and assisted primary patency post PTA of RC-AVFs were evaluated using the Kaplan-Meier analysis and log-rank test. A Cox proportional hazard model was used to identify factors associated with restenosis post PTA. The receiver operating characteristic (ROC) curve was employed to evaluate the predictive value of the risk factors for restenosis post PTA. A total of 65 patients with a mean age of 59.09±14.94years were enrolled in the study. The mean RC-AVF age was 9.2 (4.9, 35.05) months, and the median time of intervention for stenosis was 10.8 (4.05, 41.35) months after AVF creation. The primary patency rates following the first PTA at 3, 6, 12, and 24months were 93.9, 84.6, 63.1, and 55.4%, respectively. The assisted primary patency rates at 3, 6, 12, and 24months were 95.4, 90.8, 87.7, and 84.6%, respectively. Cox proportional hazard regression analysis revealed the maximum balloon diameter >5mm had a lower postoperative restenosis rate compared with the maximum balloon diameter ≤5mm (hazard ratio=0.422; 95% confidence interval [CI]: 0.201-0.884; P=0.022). ROC curve analysis showed that the area under the curve of the maximum balloon diameter during PTA was 0.624 (95% CI, 0.486-0.762). The best critical value for the maximum balloon diameter was 6mm, the sensitivity was 64.5%, and the specificity was 61.8%. For the first PTA at juxta-anastomotic of wrist RC-AVFs without thrombosis and complete occlusion, the use of a balloon with a maximum diameter of ≤5mm is a risk factor to the occurrence of restenosis within 12months post PTA. The result may help in tailoring surveillance programs in patients with RC-AVF stenosis.

An Observational Study on Transposed Brachial Artery ‒ Basilic Vein AV Fistula in Vascular Access for Hemodialysis

Background: Dialysis access in patients of chronic kidney disease (CKD) on long-term hemodialysis is a problem area. Patients with poor caliber veins distally on initial evaluation or with multiple fistula failures, basilic vein transposition is a good alternative. We present our experience with basilic vein transposition at our center. Methods: This study was a single-center observational study. A retrospective review of prospectively collected data from December 2013 to June 2019 was done. Qualitative variables were expressed as frequencies/percentages and compared between groups using the Chi-square test. Quantitative variables were expressed as mean ± standard deviation and compared between groups using unpaired t-test between groups and paired t-test within groups across follow-ups. Multiple linear regression analysis using a stepwise model selection tool was used to assess factors affecting the first cannulation. The best model was arrived in four steps where explanatory power (R 2) increased from 66.6% to 79.3% (P &lt; 0.001). Results: One hundred and eighty-eight patients formed a part of the study. One hundred and sixty-four patients underwent single stage, whereas 24 underwent two-stage transposition. Ninety-four each were male and female. The mean age was 51.38 ± 14.74 years. About 96.27% of fistulas underwent successful cannulation. The overall mean maturation time was 44.46 ± 7.21 days. It was 42.28 ± 3.71 for single and 60.27 ± 6.66 days for two-stage procedures. Primary patency at 6 months and 1 year were 92.82% and 85.67%, whereas primary-assisted patency rates were 94.6% and 91%. The secondary patency rate at 1 year was 60.77%. Salvage procedures included thrombolysis in 2, thrombectomy in 18, and thrombectomy with venoplasty in four cases. There were 28 failures. Fistula thrombosis was the most common cause. Complications included transient arm edema in 36.7%, late thrombosis in 7.7%, wound infection in 4.4%, and lymphorrhea in 6.9% of patients. Conclusion: The smallest basilic vein diameter for successful transposition is 2.5 mm. Factors used to predict successful maturation are initial vein diameter ≥2.5 mm, preoperative Peak systolic velocity (PSV) in brachial artery &gt;70 cm/s, fistula flow rate of &gt;400 ml/min at 6 weeks, and fistula diameter &gt;4.5 mm at 06 weeks.

Outcomes of a bypass-first strategy in chronic limb-threatening ischemia based on the Global Vascular Guidelines.

The Global Vascular Guidelines (GVGs) recommend initial revascularization (bypass or endovascular therapy) for chronic limb-threatening ischemia (CLTI) based on anatomical complexity and limb severity. This decision is made based on a prediction of the outcomes after endovascular intervention. This study was performed to evaluate outcomes after distal bypass in cases recommended for GVG bypass. A total of 239 distal bypasses for CLTI were evaluated in 195 patients with a GVG bypass recommendation treated between 2009 and 2020 at a single center in Japan. Comparisons were made between crural and pedal bypass cases. The 195 patients (median age, 77years; 67% male) underwent 133 crural bypasses (106 patients; 54%) and 106 pedal bypasses (89 patients; 46%). Hemodialysis was more common in pedal cases than in crural cases (P= .03). Hospital deaths occurred in two cases (1%) within 30days. The whole cohort has a follow-up rate of 96% over a mean of 28± 26months, with 3-year limb salvage rates of 87% and 3-year primary, assisted primary, and secondary patency rates of 40%, 65%, and 67%, all without significant differences between crural and pedal cases. The 1-year wound healing rate was 88% and tended to be higher in crural cases than in pedal cases (P= .068). The 3-year survival rate was 52% in the cohort and did not differ significantly between crural and pedal cases. Patients with CLTI with a GVG bypass recommendation had acceptable limb salvage, graft patency, wound healing, and survival after distal bypass, regardless of the bypass method. These findings indicate that a GVG bypass recommendation as an initial revascularization method is valid in the real world.

Effectiveness of Venous Stenting for the Treatment of Lower Extremity Chronic Thrombotic Venous Obstruction

Patients with venous hypertension have significant morbidity and poor quality of life. Deep venous thrombosis (DVT) and congenital defects that led to chronic outflow blockage are frequent causes of venous hypertension. It is known that the venovenous bypass has been the standard method used in the treatment of chronic iliofemoral vein occlusions. Percutaneous recanalization has earlier been shown to be technically possible. With venoplasty and stenting, we used an aggressive endovascular strategy to treat the iliofemoral venous thrombotic occlusion. This study aims to assess the effectiveness and safety of percutaneous venous stenting performed in our hospital for cases with chronic thrombotic venous outflow blockage of the iliofemoral vein segment. From May 2019 to April 2021, the medical records were reviewed for sixty-three patients diagnosed with symptomatic iliofemoral thrombotic occlusive disease and treated with venous stenting. The procedures' results were analyzed at Al-Azhar University Hospitals. The medical records of 63 cases (44 women with a median age of 49.52 years) with chronic outflow block of iliofemoral vein segment who were treated with endovascular venous stenting were reviewed retrospectively. Optimal success was obtained in 56 cases (88.9%). Twelve months primary, assisted primary, and secondary patency rates were 76.8%, 80.4%, and 87.5%, respectively, while it was 73.2%, 80.4%, and 87.5%, respectively, after 2 years. The procedure-related complication rate was 6.3%. Puncture site hematoma was observed in 2 patients (3.2%). Early (30-days) stent thrombosis occurred in 2 patients (3.2%). Most importantly, there was no procedure-related mortality. Endovascular treatment with balloon angioplasty and stenting of chronic venous thrombotic occlusions is an effective and safe procedure associated with a high technical rate of success and excellent patency rates. Accordingly, it should be considered the first line in the treatment of symptomatic iliofemoral vein occlusion.