[Stenotic FAV: Success of the Collaboration Between Spoke and HUB].

The arteriovenous fistula constitutes the vascular access of first choice in hemodialysis. We present three clinical cases that highlight the resolution in interventional radiology of venous stenosis, one of the major complications. Clinical monitoring and instrumental diagnostics with color Doppler ultrasound have prevented the failure of the AVF due to high risk of thrombosis. The angiographic interventions, thanks to the collaboration between Spoke and Hub, were completed without complications.

Coronary angiography was used to assess the effect of diabetes on off-pump coronary artery bypass graft patency.

This study aimed to examine the influence of diabetes on the left internal mammary artery (LIMA) and saphenous vein (SV) graft failure for 5-year follow-up. We enrolled 202 patients who underwent isolated off-pump coronary artery bypass grafting (CABG) surgery in 2014, angiographic follow-up occurred at 5 years after surgery. Angiographic outcomes in patients with or without diabetes were analyzed. Multivariate logistic regression analysis was used to identify independent predictors of graft dysfunction. A total of 66 (32.7%) patients had diabetes. Five-year rates of LIMA and SV graft failure were similar in patients with and without diabetes. In addition, in diabetics, the proportion of complete graft failure was significantly lower in the LIMA grafts (12/66, 18.2%) than in the SV grafts (57/133, 42.9%) (P = .001). In nondiabetic, the proportion of complete graft failure was also significantly lower in the LIMA grafts (28/136, 20.6%) than in the SV grafts (105/275, 38.2%) (P < .001). Multivariate logistic regression analysis showed that mean graft flow (MGF) was an independent predictor factor for LIMA (odds ratio = 1.186, 95% CI = 1.114-1.263, P < .001) and SV (odds ratio = 1.056, 95% CI = 1.035-1.077, P < .001) graft failure. Diabetes did not influence the patency of LIMA or SV grafts over a 5-year follow-up. LIMA grafts should be maximized in patients undergoing off-pump CABG surgery. Diabetes does not affect the patency of grafts CABG. Using angiography, our study proved that diabetes does not affect the patency of grafted vessels after CABG for 5 years.

[Prevalence and intervention effect of arteriovenous graft stenosis].

Objective: To evaluate the prevalence, intervention methods and effect of arteriovenous graft (AVG) stenosis. Methods: The clinical data of patients who received AVG in the Blood Purification Center, the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2022 were retrospectively analyzed. The patency rate, prevalence and intervention effect of AVG stenosis were analyzed. Results: A total of 475 patients aged (55.5±11.8) years were included, and there were 193 male cases (40.6%) and 282 female cases (59.4%). The patients were followed up for [M (Q1, Q3)] 19 (12, 30) months, and the primary, assisted primary and secondary patency were 14 (5, 27), 27 (13, 55), and 59 (33, 65) months, respectively. There were 799 access events which needed intervention, with a total standardized intervention rate of 0.90 per patient-year. Totally, 431(53.9%, 431/799) stenosis events occurred in 207 AVG. Among 422 AVG stenosis events with complete clinical data, 57.8% (244/422) were multi-site stenosis and 42.2% (178/422) were single-site stenosis. The most common sites of stenosis were graft-vein anastomosis (47.6%, 340/715), venous outflows (22.7%, 162/715), and puncture zone (20.0%, 143/715). In the 414 stenosis with intact follow-up data, 90.8% (376/414) were treated by balloon angioplasty, 8.5% (35/414) received covered stent insertion, and 0.7% (3/414) were intervened by open surgery. Clinical success rate was 98.1% (406/414). The primary patency time after endovascular treatment was 6 (4, 12) months. Covered stent significantly increased post-intervention primary patency time compared withballoon angioplasty [6 (3, 7) months vs 3 (1, 4) months, P=0.020]. Conclusions: Stenosis is the most common complication of AVG, and the most common sites are graft-vein anastomosis, venous outflows, and puncture zone. Intervention of AVG stenosis has a high clinical success rate, and a relatively low post-intervention patency. Covered stent insertion improves the post-intervention patency of AVG, which has a poor effect using balloon expansion.

[Intervention principles for complications of arteriovenous graft].

Stenosis, thrombosis, and infection are major complications of arteriovenous graft (AVG). Endovascular therapy is usually adopted for stenosis, while bypass, interposition, patch angioplasty and other surgical techniques can also be used for special sites. Interventions of AVG thrombosis include removal of thrombus and treatment of the underlying stenosis. The former includes catheter directed thrombolysis, endovascular intervention, surgical treatment, or hybrid treatment. Etiological detection before the application of empirical antibiotics is the first step of infection management. According to different infection ranges, partial graft excision and interposition, total graft excision and partial graft excision can be performed respectively. Active prevention, timely identification, and appropriate intervention of the complications can improve the long-term outcomes of AVG. Personalized interventional strategy should be employed based on the systemic evaluation.

[Factors influencing primary patency time of percutaneous transluminal balloon angioplasty for hemodialysis arteriovenous grafts].

Objective: To investigate the factors affecting primary patency time in arteriovenous graft (AVG) patients receiving percutaneous transluminal balloon angioplasty (PTA). Methods: Hemodialysis patients who underwent AVG placement at the First Affiliated Hospital of Chongqing Medical University between February 2018 and December 2021 were included. The factors including age, gender, total duration of AVG use, site of stenosis, degree of stenosis, length of stenosis, residual stenosis, and presence of thrombosis were analyzed, and influencing factors of primary patency time in AVG were determined using a multiple linear regression model. Results: A total of 101 patients who underwent 331 PTA treatments were enrolled, including 35 males and 66 females. The median age of patients undergoing PTA for the first time was 61 (51, 68) years, and the primary patency time after PTA was 5 (3, 10) months. The patients were followed up for (38.5±15.3) months. Multivariable linear regression analysis revealed that severe stenosis at the venous anastomosis and reflux veins (ß=-2.773, 95%CI:-5.440--0.105, P=0.042), female (ß=-2.247, 95%CI:-3.853--0.642, P=0.006), and previous multiple PTA treatments (ß=-0.516, 95%CI:-0.978--0.054, P=0.029) were risk factors for a shorter primary patency time after PTA. Conclusion: Severity of stenosis at the venous anastomosis and reflux veins of the AVG, female, and a history of multiple previous PTA treatments are associated with a shorter primary patency time in AVG patients.

The application of blood flow sound contrastive learning to predict arteriovenous graft stenosis of patients with hemodialysis.

End-stage kidney disease (ESKD) presents a significant public health challenge, with hemodialysis (HD) remaining one of the most prevalent kidney replacement therapies. Ensuring the longevity and functionality of arteriovenous accesses is challenging for HD patients. Blood flow sound, which contains valuable information, has often been neglected in the past. However, machine learning offers a new approach, leveraging data non-invasively and learning autonomously to match the experience of healthcare professionas. This study aimed to devise a model for detecting arteriovenous grafts (AVGs) stenosis. A smartphone stethoscope was used to record the sound of AVG blood flow at the arterial and venous sides, with each recording lasting one minute. The sound recordings were transformed into mel spectrograms, and a 14-layer convolutional neural network (CNN) was employed to detect stenosis. The CNN comprised six convolution blocks with 3x3 kernel mapping, batch normalization, and rectified linear unit activation function. We applied contrastive learning to train the pre-training audio neural networks model with unlabeled data through self-supervised learning, followed by fine-tuning. In total, 27,406 dialysis session blood flow sounds were documented, including 180 stenosis blood flow sounds. Our proposed framework demonstrated a significant improvement (p<0.05) over training from scratch and a popular pre-trained audio neural networks (PANNs) model, achieving an accuracy of 0.9279, precision of 0.8462, and recall of 0.8077, compared to previous values of 0.8649, 0.7391, and 0.6538. This study illustrates how contrastive learning with unlabeled blood flow sound data can enhance convolutional neural networks for detecting AVG stenosis in HD patients.

A review of the current recommendations and practices for hemodialysis access monitoring and maintenance procedures.

The growing number of prevalent arteriovenous (AV) accesses has been associated with an increase in the incidence of procedures being performed to maintain patency. To reduce the rate of unnecessary procedures, the 2019 Kidney Disease Outcome Quality Initiative guidelines addended the AV access surveillance recommendations, which includes clinical monitoring and assessment of dialysis adequacy alone. Abnormal clinical findings would necessitate follow-up angiography with or without confirmatory duplex ultrasound. Due to poor patency, increased surveillance schedules have been proposed to identify stenosis early and potentially prevent acute thrombotic events and AV access failure. In this review, we outlined current AV access monitoring and maintenance procedure recommendations, as described by the Centers for Medicare and Medicaid Services and 2019 Kidney Disease Outcome Quality Initiative guidelines. In addition, we highlight the findings of recently published randomized controlled trials that have examined increased surveillance schedules.

Safety and Performance of a Cell-Impermeable Endoprosthesis for Hemodialysis Vascular Access Outflow Stenosis: A Brazilian Multicenter Retrospective Study.

PURPOSE: To evaluate the safety and performance of Wrapsody™, a cell-impermeable endoprosthesis (CIE), for treating hemodialysis vascular access outflow stenosis. MATERIALS AND METHODS: Investigators retrospectively analyzed 113 hemodialysis patients treated with a CIE (11/2021-12/2022) across four centers in Brazil. De novo or restenotic lesions were treated. The primary efficacy outcome measure was target lesion primary patency (TLPP) at 1, 3, 6, and 12 months; the primary safety outcome measure was the absence of serious local or systemic adverse events within the first 30 days post-procedure. Secondary outcome measures included technical and procedural success, access circuit primary patency (ACPP), and secondary patency at 1, 3, 6, and 12 months post-procedure. RESULTS: Thirty-nine patients (34.5%) had thrombosed access at the initial presentation, and 38 patients (33.6%) presented with recurrent stenosis. TLPP rates at 1, 3, 6, and 12 months were 100%, 96.4%, 86.4%, and 69.7%, respectively. ACPP rates were 100% at 1 month, 89.2% at 3 months, 70.9% at 6 months, and 56.0% at 12 months. The target lesion secondary patency rates at 1, 3, 6, and 12 months were 100%, 97.3%, 93.6%, and 91.7%, respectively. In the adjusted multivariate Cox regression analysis, male sex and endoprosthesis with diameters of 10, 12, 14, and 16 mm were associated with improved primary patency rates. No localized or systemic serious adverse event was observed through the first 30 days post-procedure. CONCLUSION: The CIE evaluated in this study is safe and effective for treating peripheral and central outflow stenoses in hemodialysis vascular access. LEVEL OF EVIDENCE: Level 2b, cohort study.

Long-Term Patency Between Brachiocephalic and Brachiobasilic Fistulas: A Single Institution Review.

BACKGROUND: Dialysis access is a fundamental procedure performed by vascular surgeons. Commonly, upper extremity access is utilized via a brachiobasilic fistula (BBF) or brachiocephalic fistula (BCF). BCF is preferred due to ease compared to BBF without documented improved function. Few studies compare patency outcomes between BBF and BCF over time. Our goal was to evaluate the difference in outcomes between BBF and BCF. METHODS: This is a retrospective review of patients with BCF or BBF between 2019 and 2022. Patients were split by procedure: BCF and BBF. Data collected included demographics, vein size, tunneled catheter, and previous access. Primary outcomes included primary patency (PP), primary assisted patency (PAP) and secondary patency (SP). Secondary outcomes included 30-day complications, access abandonment, interventions and mortality. Linear regression, Kaplan-Meier, and log-rank test were performed. RESULTS: Our study had 184 patients, 109 (59%) with BCF and 75 (41%) with BBF. There were no differences in demographics except for body mass index and vein size (BBF: 4 vs. BCF: 3.6 mm, P = 0.020). There was no difference in PP at 1 year (41% vs. 47%, P = 0.547) or SP at 2 years (73% vs. 84%, P = 0.058) in BBF versus BCF. However, PAP was significantly greater in BCF (80% vs. 67%, P = 0.030) at 1 year. Secondary outcomes revealed no difference in wound complications (1% vs. 0%, P = 0.408), access abandonment (35% vs. 28%, P = 0.260), or number of interventions (1 vs. 1, P = 0.712) in BBF versus BCF. Mortality was significantly greater in the BBF patients (19% vs. 6%, P = 0.005). On adjusted analysis, BBF had 43 min longer operative time (P < 0.001) and 22 cc greater blood loss (P < 0.0001). CONCLUSIONS: In this single center review comparing BBF and BCF, no difference was seen between BBF and BCF in terms of PP or SP. Even with larger vein size, BBF did not confer a benefit in long term patency or access abandonment. Additionally, BBF did not confer decreased procedures to maintain patency and BBF had greater operative length and blood loss, as well as mortality. We believe this study demonstrates that for patients who must use an upper extremity location, when the cephalic vein is satisfactory, using the cephalic vein is preferred as it does not negatively impact long-term patency.

Role and Value of Intravascular Ultrasound in the End-Stage Renal Disease Population: A Narrative Review.

Vascular access for hemodialysis is the lifeline for patients with end-stage renal disease (ESRD); therefore, maintenance of the vascular access is of the utmost importance. The dialysis circuit can be complicated by stenosis or thrombosis. In particular, central venous stenosis is frequently encountered in the vascular access of patients with ESRD, and this complication may require endovascular management. Conventional catheter-based venography may be inadequate for identifying dynamic forms of extrinsic compression and intravascular webs associated with these lesions. For these types of access complications, balloon angioplasty remains the first-line intervention, with stenting reserved for selected scenarios. Accurate assessment of the venous configuration is therefore important to ensure an adequate treatment response. Intravascular ultrasound (IVUS) has been shown to be beneficial in lower extremity venous interventions. The use of IVUS in dialysis access interventions is currently limited but may be indicated in selected challenging clinical situations. In this article, we discuss the potential uses of IVUS in the ESRD population based on our institutional experience and on the current literature.

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.

Graft Patency and Clinical Outcomes in Patients With Radial Artery Grafts Previously Instrumented for Cardiac Catheterization.

BACKGROUND: While transradial access is favored for cardiac catheterization, the radial artery (RA) is increasingly preferred for coronary artery bypass grafting. Whether the RA is suitable for use as a graft following instrumentation for transradial access remains uncertain. METHODS: Consecutive patients from 2015 to 2019 who underwent coronary artery bypass grafting using both the left and right RAs as grafts were included. Instrumented RAs underwent careful preoperative assessment for suitability. The clinical analysis was stratified by whether patients received an instrumented RA graft (instrumented versus noninstrumented groups). Eligible patients with both instrumented and noninstrumented RAs underwent computed tomography coronary angiography to evaluate graft patency. The primary outcome was a within-patient paired analysis of graft patency comparing instrumented to noninstrumented RA grafts. RESULTS: Of the 1123 patients who underwent coronary artery bypass grafting, 294 had both the left and right RAs used as grafts and were included. There were 126 and 168 patients in the instrumented and noninstrumented groups, respectively. Baseline characteristics and perioperative outcomes were comparable. The rate of major adverse cardiac events at 2 years following coronary artery bypass grafting was 2.4% in the instrumented group and 5.4% in the noninstrumented group (hazard ratio, 0.44 [95% CI, 0.12-1.61]; P=0.19). There were 50 patients included in the graft patency analysis. At a median follow-up of 4.3 (interquartile range, 3.7-4.5) years, 40/50 (80%) instrumented and 41/50 (82%) noninstrumented grafts were patent (odds ratio, 0.86 [95% CI, 0.29-2.52]; P>0.99). No significant differences were observed in the luminal diameter or cross-sectional area of the instrumented and noninstrumented RA grafts. CONCLUSIONS: There was no evidence found in this study that RA graft patency was affected by prior transradial access, and the use of an instrumented RA was not associated with worse outcomes in the exploratory clinical analysis. Although conduits must be carefully selected, prior transradial access should not be considered an absolute contraindication to the use of the RA as a bypass graft. REGISTRATION: URL: https://www.anzctr.org.au/; Unique identifier: ACTRN12621000257864.

Drug-coated balloons versus conventional percutaneous transluminal angioplasty for treatment-naïve dysfunctional arteriovenous fistulas.: A 10-year single center retrospective study.

OBJECTIVES: To compare the primary patency and restenosis rates in treatment naieve dialysis arteriovenous fistulas (AVFs) after drug-coated balloons (DCB) versus plain balloon angioplasty (PTA). METHODS: This retrospective study included 157 patients who underwent AVF angioplasty for treatment-native AVF stenosis between January 2012 to 2022. The fistulas were Brachiocephalic (75%), Brachiobasilic (17%), and radiocephalic (8%). The index intervention was with either DCB or percutaneous transluminal angioplasty (PTA) with subsequent follow up. Patients with central venous stenosis, thrombosed fistula, fistula stents, AV graft or surgical intervention after the index procedure were excluded. RESULTS: Arteriovenous fistula angioplasty was done in 28 patients using DCB and in 129 patients using PTA. A total of 108 patients presented with a single stenosis, 42 with 2 stenoses, and 7 with 3 stenoses. The location of these stenoses was in the venous outflow (57%), the juxta anastomotic segment (31%), and cephalic arch (12%). The median time to re-intervention for the PTA was 216 days compared to 304 days for the DCB (p=0.079). Primary patency at 6 months was 60.4% for PTA and 75% for DCB (p=0.141) CONCLUSION: Although DCB angioplasty of treatmentnaïve dysfunctional AVF tends to improve the time to intervention and 6-month primary patency compared to PTA, this difference did not reach statistical significance.

Pathohistomorphometric and Immuno-Histologic Changes in Early Arteriovenous Fistula Failure in Patients with Chronic Kidney Disease.

BACKGROUND: Hemodialysis is a prevalent treatment for the end-stage chronic kidney disease (CKD) worldwide. The primary arteriovenous fistula (AVF), widely considered the optimal hemodialysis access method, fails to mature in up to two-thirds of the cases. The etiology of the early AVF failure, defined as thrombosis or inability to use within three months post-creation remains less understood, and is influenced by various factors including patient demographics, surgical techniques, and genetic predispositions. Neointimal hyperplasia is a primary histological finding in stenotic lesions leading to the AVF failure. However, there are insufficient data on the cellular phenotypes and the impact of the preexisting CKD-related factors. This study aims to investigate the histological, morphometric, and immunohistochemical alterations in the fistula vein, pre-, peri-, and post-early failure. MATERIALS AND METHODS: Eighty-nine stage 4-5 CKD patients underwent standard preoperative assessment, including the Doppler ultrasound, before a typical radio-cephalic AVF creation. Post-failure, a new AVF was created proximally. The vein specimens were collected during the surgery, processed, and analyzed for morphometric analyses and various cellular markers, including Vimentin, TGF, and Ki 67. RESULTS: The study enrolled 89 CKD patients, analyzing various aspects of their condition and AVF failures. The histomorphometric analysis revealed substantial venous luminal stenosis and varied endothelial changes. The immunohistologic analysis showed differential marker expressions pre- and post-AVF creation. CONCLUSION: This study highlights the complexity of the early AVF failures in CKD patients. The medial hypertrophy emerged as a significant preexisting lesion, while the postoperative analyses indicated a shift towards neointimal hyperplasia. The research underscores the nuanced interplay of vascular remodeling, endothelial damage, and cellular proliferation in the AVF outcomes.

Endograft Thrombosis as an Indication for Open Conversion after Endovascular Aneurysm Repair in a Multicenter Experience over 25 Years.

BACKGROUND: To describe the outcomes of aortic endograft thrombosis (AET) as an indication for open conversion (OC) after endovascular aortic aneurysm repair (EVAR) in a multicenter experience. METHODS: This study retrospectively analyzed cases of OC for AET following EVAR across 12 Italian Vascular Surgery centers from 1997 to September 2022. The end points were as follows: 30-day mortality and major postoperative complications. Follow-up data included survival and aortic-related complications. RESULTS: Sixteen patients (mean age: 68.6 ± 8.5 years) were included. The median elapsed time between EVAR and OC was 26.46 months (interquartile range: 13.8-45.9). Proximal aortic cross-clamping site was supraceliac in 8 out of 16 (50%) patients, and complete removal of the stentgraft was achieved in 75% of cases (12/16 patients). Reconstructions were aorto-bi-iliac grafts in 8 cases (50%), 7 aortobifemoral bypass grafts (43.8%), and 1 aortoaortic tube graft (6.3%). All patients were symptomatic at presentation (68.7% unilateral acute limb ischemia, 25% bilateral acute limb ischemia, 1 patient had chronic severe claudication). Thirty-day mortality was 12.5% (2/16 patients). The overall morbidity rate was 43.8% (7 of 16 patients). No specific risk factors for early mortality were found. The overall estimated survival rate was 80.4% at 1 year, 62.5% at 2 years, and 41.7% at 3 years. CONCLUSIONS: OC for AET is typically reserved for complex cases that are not amenable to endovascular solutions. The frequent need for suprarenal clamping and complete endograft removal seems to be associated with high short-term mortality.

Clinical outcomes and predictive factors of stent grafts treatment for symptomatic central venous obstruction in end stage kidney disease patients with arteriovenous access.

To assess the efficacy of stent grafts (SGs) in managing central venous obstruction disease (CVOD) in hemodialysis (HD) patients with arteriovenous (AV) access, and to identify predictive factors influencing the SG treatment outcomes. HD subjects with CVOD who underwent SGs placement at our center between August 2018 and June 2022 were enrolled. Survival curve analysis using the Kaplan-Meier method and log-rank test was performed. Cox proportional hazards regression analysis was employed to identify predictive factors associated with outcomes. A total of 59 SG implantation procedures for CVOD were analyzed, comprising 30 cases of stenosis and 29 cases of occlusion. The access circuit primary patency (ACPP) at 6, 12, and 24 months post-SG placement were 80.9%, 53.8%, and 31.4%, respectively, while, the target lesion primary patency (TLPP) were 91.3%, 67.6%, and 44.5%, respectively. Subgroup analysis revealed higher TLPP in the stenosis group compared to the occlusion group, although the difference was not statistically significant (P = 0.165). The TLPP was significantly improved by SG placement in those who had antecedent balloon dilations (P < 0.001). Cox proportional hazards regression identified target lesion length ≥ 30 mm and procedure defects as independent predictors of lower TLPP after SG treatment for CVOD in HD patients. SG placement demonstrates safety and efficacy in managing CVOD among HD patients, leading to improved TLPP of endovascular therapy (EVT) for CVOD. Notably, long target lesions (≥ 30 mm) and procedure defects emerged as predictive factors influencing TLPP.

Descriptive Analysis of Amputation-Free Survival After First Time Infra-Inguinal Bypass Occlusion.

INTRODUCTION: Occlusion after infra-inguinal bypass surgery for peripheral artery disease is a major complication with potentially devastating consequences. In this descriptive analysis, we sought to describe the natural history and explore factors associated with long-term major amputation-free survival following occlusion of a first-time infra-inguinal bypass. METHODS: Using a prospective database from a tertiary care vascular center, we conducted a retrospective cohort study of all patients with peripheral artery disease who underwent a first-time infra-inguinal bypass and subsequently suffered a graft occlusion (1997-2021). The primary outcome was longitudinal rate of major amputation-free survival after bypass occlusion. Cox proportional hazard models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to explore predictors of outcomes. RESULTS: Of the 1318 first-time infra-inguinal bypass surgeries performed over the study period, 255 bypasses occluded and were included in our analysis. Mean age was 66.7 (12.6) years, 40.4% were female, and indication for index bypass was chronic limb threatening ischemia (CLTI) in 89.8% (n = 229). 48.2% (n = 123) of index bypass conduits used great saphenous vein, 29.0% (n = 74) prosthetic graft, and 22.8% (n = 58) an alternative conduit. Median (interquartile range) time to bypass occlusion was 6.8 (2.3-19.0) months, and patients were followed for median of 4.3 (1.7-8.1) years after bypass occlusion. Following occlusion, 38.04% underwent no revascularization, 32.94% graft salvage procedure, 25.1% new bypass, and 3.92% native artery recanalization. Major amputation-free survival following occlusion was 56.9% (50.6%-62.8%) at 1 y, 37.1% (31%-43.3%) at 5 y, and 17.2% (11.9%-23.2%) at 10 y. In multivariable analysis, factors associated with lower amputation-free survival were older age, female sex, advanced cardiorenal comorbidities, CLTI at index procedure, CLTI at time of occlusion, and distal index bypass outflow. Initial treatment after occlusion with both a new surgical bypass (HR 0.44, CI: 0.29-0.67) or a graft salvage procedure (HR 0.56, CI: 0.38-0.82) showed improved amputation-free survival. One-year rate of major amputation or death were 59.8% (50.0%-69.6%) for those who underwent no revascularization, 37.9% (28.7%-49.0%) for graft salvage, and 26.7% (17.6%-39.5%) for new bypass. CONCLUSIONS: Long-term major amputation-free survival is low after occlusion of a first-time infra-inguinal bypass. While several nonmodifiable risk factors were associated with lower amputation-free survival, treatment after graft occlusion with either a new bypass or a graft salvage procedure may improve longitudinal outcomes.