Arteriovenous Graft Thrombosis Research Articles

Percutaneous Pharmacological Thrombolysis as an Effective Primary Mode of Management of Thrombosed Prosthetic Arterio-Venous Grafts

Abstract Background Thrombosis of prosthetic arterio-venous graft (PAVG) is the most common cause of failure of using this access for haemodialysis (HD) in end stage kidney disease (ESKD) patients. Many different open surgical and vascular techniques were described to restore the function of thrombosed PAVG. Objectives We wanted to assess the feasibility and patency rates following the continuous thrombolysis infusion using tissue Plasminogen Activator (tPA) followed by angiogram and angioplasty of stenotic segment(s) in thrombosed PAVG. Methods We performed retrospective analysis of prospectively collected data from patients who had a thrombosed AVG from January 2020 to January 2022. Thrombolysis took place maximum 7 days after thrombosis was diagnosed. We have excluded patients who were referred to us more than a week after thrombosis occurred and patients with relative or absolute contraindication for thrombolysis and/or anticoagulation. Results During the two years of the study, there were 58 patients referred to our centre with thrombosed PAVG. We have excluded 28 patients who didn’t fulfill inclusion criteria. We have performed PAVG continuous thrombolysis infusion using tPA till we have achieved reopening of the thrombosed PAVG followed by angiography and angioplasty. All patients had venous anastomosis stenosis while 17 patients had stenosis in the graft and only 5 had a stenosis at the arterial anastomosis. During the period of follow up primary patency was achieved in 80% of our patients while our primary assisted patency was 86.67% Conclusions Endovascular tPA thrombolysis for early thrombosis of prosthetic AVAs is feasible, safe, and is associated with an excellent technical success and very good 12 months patency rate.

Efficacy and safety of Apixaban for the prevention of thrombosis in arteriovenous grafts.

This research aims to fill a vital gap in existing studies by evaluating the efficacy and safety of Apixaban, a direct oral anticoagulant, in the prevention of arteriovenous graft (AVG) thrombosis, thereby offering substantial insights into alternative anticoagulant options for hemodialysis patients. Conducted as a multi-center, randomized, double-blind, placebo-controlled trial, this study involved end-stage renal disease (ESRD) patients who had recently received polytetrafluoroethylene grafts. Participants were assigned to receive either Apixaban at a dose of 2.5 mg twice daily or a placebo. The primary outcome measure was the occurrence of graft thrombosis, while secondary outcomes focused on the incidence and severity of bleeding. Analytical methods included Kaplan-Meier estimates, Cox proportional hazards models, and conventional statistical tests. With 96 patients enrolled, the study found that Apixaban significantly reduced the incidence of AVG thrombosis compared to placebo (16.7% vs. 62.5%, P < 0.0001). Notably, this reduction in thrombosis incidence was not accompanied by an increase in bleeding events, thus affirming the safety profile of Apixaban as established in prior research. Apixaban is identified as an efficacious alternative to traditional anticoagulants in the prevention of AVG thrombosis among hemodialysis patients, representing a notable advancement in the care of individuals with ESRD. The results of this study support further investigations into the optimal dosing strategies specifically tailored for this patient demographic.

Color Doppler ultrasound evaluation of arteriovenous grafts for hemodialysis.

Although arteriovenous fistula (AVF) continues to be the vascular access of choice for the hemodialysis, arteriovenous graft (AVG) can be the best choice in certain categories of patients and could have several advantages over AVF in a "patient centered approach" to vascular access. In the clinical management of prosthetic fistulas, color Doppler ultrasound (CDU) is the imaging method of choice for identifying stenosis and other AVG complications. In this review, besides highlighting the pivotal role of CDU in the diagnosis of AVG complications, we will underline the key role that ultrasound can play in identifying those stenosis most likely to cause AVG thrombosis. Furthermore, we will emphasize the support that CDU can play in distinguishing the different types of grafts and prosthetic devices such as stent-grafts, in identifying AVG with lower survival, CDU utilities and limitations in the evaluation of freshly-implanted grafts, the different sites available for AVG volume flow measurement and their use based on the configuration of the prosthesis, the time interval elapsed from the surgical intervention and the integrity of the prosthetic walls.

EE437 Economic Value of Covered Expanded Polytetrafluoroethylene (EPTFE) Stent Grafts Compared to Percutaneous Balloon Angioplasty for Treating Thrombosed and Dysfunctional Arteriovenous Grafts in Hemodialysis Patients in Germany

Hemodialysis patients with an arteriovenous graft (AVG) implant can experience AVG stenosis and thrombosis which require further procedural revision to maintain an open circuit for hemodialysis. This analysis aims to establish the economic value of revising an AVG with a covered stent graft compared to percutaneous balloon angioplasty (PTA) using clinical and resource use data from the Gore REVISE Clinical Study along with cost data specific to German treatment setting.

SUPERA stent placement for salvaging early recurrent arteriovenous graft thrombosis after percutaneous transluminal angioplasty: A single-center study.

The aim of this study was to evaluate the patency of the helical interwoven SUPERA stent for salvaging prosthetic arteriovenous (AV) grafts with rapidly recurrent thrombotic occlusion developed within a short time period after successful percutaneous transluminal angioplasty. From December 2019 to September 2021, the data of 20 patients with AV graft who had the SUPERA stent inserted satisfying the following conditions were consecutively collected. (1) More than 1 year has passed since the AV access operation; (2) Thrombotic re-occlusion of AV graft occurred within 3 months after previous successful endovascular treatment; (3) Residual stenosis is greater than 30% after full effacement of balloon angioplasty in the primary lesion. Post-interventional target lesion primary patency (TLPP), access circuit primary patency (ACPP), and secondary patency (SP) were calculated. Primary lesions of early recurrent arteriovenous graft thrombosis were found in 13 patients with graft-vein anastomosis, six patients with intra-graft stenosis, and one patient with outflow vein complications. The lesions showed residual stenosis in 47.4% (interquartile range: 44.1%-55.3%) of patients despite full-effacement balloon angioplasty. Clinical success was achieved in all patients with full-expansion of the stents at the 1-month follow-up. The TLPP was 70.7% and 32% at 6 and 12 months, respectively, and ACPP was 47.5% and 6.8% at 6 and 12 months, respectively. The SP was 76.1% and 57.1% at 6 and 12 months, respectively. No cannulation complications occurred in the six patients with installation inside the graft. No hemodialysis or stent fracture occurred in any patient during the follow-up period. The SUPERA stent may have a role in salvaging AV grafts with early recurrent thrombosis due to its greater radial force and its conformability and can be useful in treating stenosis involving the elbow or axilla, with fair patency and low complication rates.

Role of Antiplatelet Therapy in Hemodialysis Arteriovenous Graft Secondary Patency Following Successful Percutaneous Thrombectomy.

The purpose of this study was to elicit the relationship of antiplatelet therapy (AP) in maintaining arteriovenous graft (AVG) patency after successful percutaneous pharmacomechanical thrombectomy ("declot"). This was an institutional review board-approved retrospective review of AVG declot procedures between July 2019 and August 2020. AVG characteristics, bleeding complications, anticoagulation and antiplatelet medication regimens, and thrombosis free survival were evaluated. Recurrent time-to-event analysis was performed using a Prentice-Williams-Peterson Gap time model was performed to evaluate AVG thrombosis free survival. A total of 109 declots were technically successful and performed in 63 individual patients. The majority of procedures were performed in upper arm grafts (71%, n = 45). Dual antiplatelet (DAPT) was prescribed after 52 declots (48%), single antiplatelet was prescribed after 36 declots (33%), and anticoagulation was prescribed after 31 declots (28%). Median thrombosis free survival was 37days (range 1-412days) in the no antiplatelet group, 84days (range 1-427days) in the single antiplatelet group, and 93days (range 3-407days) in the DAPT group. Anti-platelet medications trended towards protective of AVG thrombosis in multivariate analysis (hazard ratio 0.84, 95% confidence interval 0.60-1.19); however, this did not reach statistical significance (P = 0.33). A total of 4 major and 5 minor bleeding events occurred. The results of this study support further evaluation of AP therapy in preventing secondary rethrombosis of dialysis AVG.

The role of vacuum-assisted mechanical thrombectomy in the management of acutely thrombosed arteriovenous fistulas and grafts.

The purpose of this study is to evaluate the safety and efficacy of the mechanical thrombectomy with the Indigo System in the treatment of thrombosed arteriovenous fistulas and grafts. A retrospective search of endovascular procedures performed from November 2018 to June 2020 was conducted. Inclusion criteria were: acute arteriovenous fistula or graft thrombosis that underwent endovascular mechanical thrombectomy with Indigo System. The following information was collected from each case: sex, age, fistula modality, fistula location, treatment modality, and outcomes. Endpoints evaluated were: technical and clinical success rates; primary, assisted primary, and secondary patency rates; complication rates. Twenty-six mechanical thrombectomy procedures for declotting of arteriovenous fistula thrombosis, using the Indigo System, were performed in 22 patients. Technical and clinical success was achieved in 23/26 cases (88%). Mean follow-up was 9 months (range 11-539 days). The 6-month primary, primary assisted, and secondary patency rates were 71%, 86%, 93% and the 12-month primary, primary assisted, and secondary patency rates were 71%, 72%, 80%, respectively. No technical or device-related complications were observed during thrombectomy, however two venous ruptures occurred on the angioplasty of the underlying stenosis. In conclusion, vacuum-assisted thrombectomy of acutely thrombosed arteriovenous fistulas and grafts with Indigo System is safe and effective, providing good short term patency rates.

The Impact of Seasonality on Prosthetic Arteriovenous Vascular Access Graft Thrombosis

Highlights Abstract Introduction: Arteriovenous prosthetic grafts are susceptible to recurrent thrombotic occlusions mainly due to venous outflow disease secondary to neointimal hyperplasia. Maintenance of vascular access for dialysis is a perpetual challenge for both patients and health care systems. In regions with hotter climates, there is a clinical impression that episodes of prosthetic arteriovenous vascular access graft thrombosis are more frequent during hot dry summers secondary to dehydration and increased blood viscosity. Seasonality of thrombotic events has been observed in multiple vascular beds. However, a seasonal pattern or any association of arteriovenous graft thrombosis with temperature and relative humidity levels has never been fully demonstrated. Methods: Data were collected prospectively from January 2014 until December 2020 but analyzed retrospectively. In this 7-year timeframe, 289 episodes of arteriovenous graft thrombosis were identified from 142 grafts fashioned. Results: No monthly variation (P = 0.35) or seasonal variation (P = 0.91) was identified. No statistically significant correlation between episodes of thrombosis and mean monthly temperature and mean relative humidity was noted. Conclusion: No evidence was identified to support this theory. However, multiple issues with assessments of events must be conceded. Graft thrombosis is multifactorial in nature, and venous outflow disease contributes toward a significant number of these events. Within our local cohort, a low primary patency rate was identified, which further contributes to graft interventions. Relatively small numbers were recruited, and therefore, potential correlations could have been missed.

The role of venous pressure variability during hemodialysis in the prediction of impending arteriovenous graft occlusion.

Elevated venous pressure during hemodialysis (VPHD) is associated with arteriovenous graft (AVG) stenosis. This study investigated the role of VPHD variations in the prediction of impending AVG occlusion. Data were retrieved from 118 operations to treat AVG occlusion (occlusion group) and 149 operations to treat significant AVG stenosis (stenosis group). In addition to analyzing the VPHD values for the three hemodialysis (HD) sessions prior to the intervention, VPHD values were normalized to mean blood pressure (MBP), blood flow rate (BFR), BFR × MBP, and BFR2 × MBP to yield ratios for analysis. The coefficient of variation (CV) was used to measure relative variations. The within-group comparisons for both groups revealed no significant differences in the VPHD mean and CV values among the three HD sessions prior to intervention. However, the CVs for VPHD/MBP, VPHD/(BFR × MBP), and VPHD/(BFR2 × MBP) exhibited significant elevation in the occlusion group during the last HD session prior to intervention compared with both the penultimate and antepenultimate within-group HD data (p < 0.05). In the receiver operating characteristic curve analysis, the CV for VPHD/(BFR2 × MBP) was the only parameter able to discriminate between the last and the penultimate HD outcomes (p < 0.001). According to a multivariate analysis, after controlling for covariates, CV for VPHD/(BFR2 × MBP) >8.76% was associated with a higher risk of AVG thrombosis (odds ratio: 3.17, p < 0.001). Increasing the variation in VPHD/(BFR2 × MBP) may increase the probability of AVG occlusion.

The management of dialysis access thrombosis during the COVID-19 pandemic.

Maintaining patent access is essential for haemodialysis dependent end stage renal failure patients. The COVID-19 pandemic has significantly affected surgical and interventional radiology services worldwide. We aimed to review the impact COVID-19 has caused to the management of acute dialysis access thrombosis. We conducted a single centre retrospective review of outcomes of patients with arteriovenous fistula and arteriovenous graft thrombosis between March and May 2020, which coincided with the first peak of the COVID-19 pandemic in London, and a similar period in the previous year, March-May 2019. Outcomes in both cohorts of patients were compared, including attempts at salvage, salvage success, 1-month patency rates after salvage and subsequent surgery on the same access. We also analysed the use of tunnelled haemodialysis lines (THL), either due to failed salvage attempts or when salvage was not attempted. There was a similar incidence of access thrombosis in both periods (26 cases in 2019, 38 in 2020). There were 601 patients dialysing via an arteriovenous fistula or graft in 2019, and 568 patients in 2020. Access salvage, when attempted, had similar success rates and 1-month patency (salvage success 74% vs 80%, p = 0.39; 1-month patency 55% vs 62%, p = 0.69). The proportion of patients where access salvage was not attempted and a THL inserted was significantly higher in 2020 compared to 2019 (32% vs 4%, p = 0.007). There were more patients who subsequently had surgery to salvage or revise the same access in 2019 compared to 2020 (62% vs 13%, p < 0.001). During the peak of the COVID-19 pandemic, there were fewer attempts at access salvage. This was a conscious decision due to increased pressure on the healthcare system, access to emergency interventional radiology or operative theatres and the perceived risk/benefit ratio of access salvage. The long-term effects of this change in practice remain unknown.

A Case of Brachial Artery Thrombosis Caused by Massage of an Occluded Arteriovenous Graft

Background: Acute upper limb ischemia (AULI) is a potential complication associated with massages of occluded vascular accesses in patients undergoing hemodialysis. Pharmacological thrombolysis, endovascular intervention and surgical intervention are possible treatment options. Deciding the appropriate treatment strategy is still a controversial issue. Case Presentation: The patient was a 43-year-old woman with renal failure who underwent hemodialysis and peritoneal dialysis. She was found to have an arteriovenous graft (AVG) thrombosis at the start of a hemodialysis session. She underwent massage of the vascular access, and immediately after the massage, she reported pain and cyanosis in her right-hand fingers and was referred to our hospital. Duplex ultrasonography revealed a large number of thrombi in the brachial, radial and ulnar arteries. AULI due to brachial artery thrombosis was diagnosed and surgical intervention was performed on the same day. The vascular wall of the forearm artery was incised vertically against the running vessel and thrombi around the bifurcation of the radial and ulnar arteries were removed. Angiography guided-surgical intervention was performed and improvement in blood flow was achieved. The patient was discharged on the second day after the operation. Conclusion: Surgical intervention has been reported as an effective treatment of AULI due to brachial artery thrombosis after massage of an occluded vascular access.

Endovascular treatment of arteriovenous graft dysfunction as a result of graft delamination and fracture

BackgroundGraft thrombosis due to fabric delamination is a rare cause of delayed failure of arteriovenous grafts. Graft delamination is primarily an imaging diagnosis and is confirmed with the help of ultrasound which shows the separation of graft fabric layers. Only two such cases have been described in the literature so far.Case presentationWe present a case of upper extremity arteriovenous graft thrombosis in a 79 year old COVID-19 positive patient with end-stage renal disease. The diagnosis was established on ultrasonography which revealed separation of the graft fabric layers with thrombosis within the “false” and “true” lumen of the graft. The patient was managed with angioplasty and embolectomy of the clot material followed by stent-graft placement across the delaminated portion of the graft. Post-procedural angiography confirmed brisk flow across the graft and patient could successfully have subsequent hemodialysis sessions.ConclusionsIdentification of graft delamination as a cause of graft failure is important as its management differs from other conventional causes since it requires stent-grafts to cover the area of delamination to re-establish flow and salvage the AV graft. The recognition of this phenomenon is essential to provide quality care and successful reuse of the AV graft.Level of evidenceLevel 4, Case Report.

Comparable Patency of Open and Hybrid Treatment of Venous Anastomotic Lesions in Thrombosed Haemodialysis Grafts

Arteriovenous graft (AVG) failures are typically associated with venous anastomotic (VA) stenosis. Current evidence regarding AVG thrombosis management compares surgical with purely endovascular techniques; few studies have investigated the "hybrid" intervention that combines surgical balloon thrombectomy and endovascular angioplasty and/or stenting to address VA obstruction. This study aimed to describe outcomes after hybrid intervention compared with open revision (patch venoplasty or jump bypass) of the VA in thrombosed AVGs. Retrospective cohort study. Consecutive patients with a thrombosed AVG who underwent thrombectomy between January 2014 and July 2018 were divided into open and hybrid groups based on VA intervention; patients who underwent purely endovascular thrombectomy were excluded. Patient demographics, previous access history, central vein patency, AVG anatomy, type of intervention, and follow up data were recorded. Kaplan-Meier curves were used to analyse time from thrombectomy to first re-intervention (primary patency) and time to abandonment (secondary patency). Cox regression analysis was performed to evaluate predictors of failure. This study included 97 patients (54 females) with 39 forearm, 47 upper arm, and 11 lower extremity AVGs. There were 34 open revisions (25 patches, nine jump bypasses) and 63 hybrid interventions, which included balloon angioplasty±adjunctive procedures (15 stents, five cutting balloons). Technique selection was based on physician preference. Primary patency for the open and hybrid groups was 27.8% and 34.2%, respectively, at six months and 17.5% and 12.9%, respectively, at 12 months (p=.71). Secondary patency was 45.1% and 38.5% for open and hybrid treatment, respectively, at 12 months (p=.87). An existing VA stent was predictive of graft abandonment (hazard ratio 4.4, 95% confidence interval 1.2-16.0; p=.024). Open vs. hybrid intervention was not predictive of failure or abandonment. Hybrid interventions for thrombosed AVGs are not associated with worse patency at six and 12 months compared with open revision.

Comparison between endovascular versus hybrid thrombectomy for arteriovenous graft under complete ultrasound guidance.

Endovascular treatment of acute thrombosed arteriovenous grafts performed completely under ultrasound guidance has rarely been reported. We compared the efficacy of a new endovascular thrombectomy technique (percutaneous manual thromboaspiration through the introducer sheath) with classical hybrid thrombectomy (minimally invasive surgical thrombectomy combined with high-pressure angioplasty) performed completely under ultrasound guidance, for arteriovenous graft thrombosis. This was a retrospective cohort study involving patients receiving hemodialysis who underwent arteriovenous graft thrombectomy between January 2014 and December 2017. We divided 130 participants into an intervention (endovascular) group (N.=65) and a control (classical hybrid) group (N.=65) according to the thrombectomy technique. The procedural success rate, immediate outcomes and patency were compared between the groups. There was no significant difference in the procedural success rate (92.31% vs. 89.23%, P=0.55) between the intervention and control groups, respectively. No major complications were noted, but two cases of vessel rupture occurred in the control group and three cases of vessel rupture occurred in the intervention group. The procedure time in the intervention group was significantly shorter than that in the control group (74±14.21 min vs. 109.05±19.20 min, respectively; P<0.05). During the 6-month follow-up, we found no significant difference in the postintervention primary patency rate (48.33% vs. 55.17%; P=0.51) or the postintervention second patency rate (83.33% vs. 84.49%; P=0.79) between the intervention and control groups, respectively. Dialysis clearance and ≥50% stenosis were predictors of postintervention primary patency (hazard ratio, 7.80; 95% confidence interval: 1.75-34.81; P=0.01; and hazard ratio, 6.43; 95% confidence interval: 2.43-17.03; P<0.001), respectively. Completely ultrasound-guided percutaneous manual thromboaspiration through the introducer sheath can be used for thrombosed arteriovenous grafts. This approach has the advantage of shorter operative time compared with hybrid treatment.

SAT-219 OUTCOMES OF PREGNANCY AMONG CHRONIC HEMODIALYSIS PATIENTS

Pregnancy in end stage renal disease (ESRD) women is uncommon and the risk for maternal - fetal complications is high. The rate of successful pregnancies in chronic hemodialysis (HD) patients has improved over the last decade up to 80%. Multidisciplinary team care and intensified hemodialysis regimens contributed in this substantial impact. We are reporting the outcomes of pregnancy in hemodialysis patients from single hemodialysis center in United Arab Emirates. A retrospective chart review study was conducted at Tawam hospital hemodialysis unit (capacity of 380 patients) over 10 years (Jan 2009 – June 2019). We included all cases of female HD patients get pregnant during study period. Demographic, clinical and laboratory data were collected as well as pregnancy outcomes, maternal and fetal complications were analyzed using descriptive analysis. we identified a total of 5 female ESRD patients on HD, with a total of 7 pregnancies. The mean age was 35.5 years. Three patients were expatriates. The causes of ESRD were type 1 diabetes (2), type 2 diabetes (1), systemic lupus erythematosus (1) and adult polycystic kidney disease (1). Other comorbid conditions were anemia of renal disease (5), hypertension (4), dyslipidemia (4), obesity (2), history of ischemic heart disease (IHD) (1) and peripheral vascular disease (PVD) (1). The average duration on hemodialysis at time of pregnancy was ranging from 3 months to 7 years and two patients were initiated on HD in the first 10 weeks of pregnancy. Three patients were multiparous prior to ESRD, with total number of children (11) and abortion/ fetal death (7). All the 5 patients had spontaneous pregnancies. The frequency of HD increased to 5-6 times per week with 4 hours duration with average pre-dialysis urea levels of 10.5 to 12 mmol/L Qutaiba Hussain*,. The maternal complications during pregnancy in our cohort including: urinary tract infection (1), diabetic foot infection (1), anemia required blood transfusion (3), renal cyst rupture (1), recurrent arteriovenous graft thrombosis (1), preeclampsia (3), premature preterm rapture of membrane (PPROM) and abruptio placenta (2). The successful outcomes of pregnancies were three live births required c sections for preterm delivery at 30 – 34 weeks (2 emergency c/sections for preeclampsia and abruptio placenta). A patient had advanced diabetic type 1 complications with IHD, PVD had a total of 3 pregnancies with poor outcomes due to uteroplacental insufficiency (one fetal death at 25 weeks, one severe intrauterine growth restriction (IUGR)/preeclampsia, and one with PPROM/ IUGR). The fetal complications identified were preterm delivery (3), fetal death (1), post-delivery death (2), severe IUGR (3), abortion (1) and fetal anomalies (2) [anhydramnios (1), membranous ventricular septal defect VSD (1)]. Pregnancy in chronic hemodialysis patients with advanced comorbid conditions has high risk for complications and need comprehensive care. We had a total of 7 pregnancies over 10 years with successful outcomes in three patients (42.8%).

Factors influencing outcomes of rheolytic thrombectomy on thrombosed dialysis access grafts: Door to angiographic bed time and what else?

The aim of this study was to investigate the effect of the time interval from clinical presentation of arteriovenous graft thrombosis and the thrombectomy procedure by the AngioJet system in terms of technical and clinical success and to identify factors influencing success. A total of 60 consecutive patients (35 men and 25 women; mean age = 52 ± 7.89 years) who had undergone percutaneous thrombectomy by the AngioJet device from 2016 to 2019 were retrospectively enrolled. Demographics and fistula data, previous treatments, time from clinical onset of thrombosis to intervention, procedural details and complications were recorded. Technical and clinical success and primary and secondary patency rates were calculated. One-way analysis of variance was performed to test any correlation between patient-related and fistula/procedure-related variables and technical/clinical success. Odds ratio and relative risk were also calculated when necessary. Technical success and clinical success were 95% and 91.7%, respectively. Post-interventional primary and secondary patency rates at 1 year were 72.5% and 84.3%, respectively. Complication rate was 6.7%. One-way analysis of variance showed that clinical success was higher in patients with no previous treatment (p = 0.015). Furthermore, clinical success was significantly associated with door to angiographic bed time (p = 0.002): p-value for the 24-h and the 72-h cut-off was 0.012 and 0.006, respectively. Percutaneous rheolytic thrombectomy is safe and effective for thrombosed arteriovenous grafts, with acceptable primary and secondary patency rates. Higher clinical success was found in patients never treated before and when the procedure was carried out within 24 h from the clinical onset of thrombosis.

Vacuum-assisted mechanical thrombectomy in extensively occlusive thrombosis of dialysis arteriovenous grafts with indigo system.

To present a selected series of extensively occlusive thrombosis of arteriovenous graft treated with the Penumbra's Indigo System. Ten patients with acute (within 72 h) extensively occlusive thrombosis of arteriovenous graft (mean extension = 30.1 (range = 15-45) cm) were treated at our institution with the Indigo System. Of the 10 cases, thrombosis was extended to venous outflow in 7 cases and to both arterial inflow and venous outflow in 3 cases. Both anatomic and clinical success were achieved in 8 of the 10 procedures (80.0%). In the 2 cases of technical failure, the patients underwent surgical thrombectomy with the finding of arteriovenous graft exhaustion, which was then replaced. The 6-month primary patency, primary-assisted patency, and secondary patency rates were 37.5% (3/8), 50.0% (4/8), and 62.5% (5/8). We reported 2 complications (one minor and one major adverse event). Percutaneous mechanical thrombectomy aspiration with Indigo System is a relatively safe and effective procedure and can be used even in extensively thrombosed arteriovenous graft.

Arteriovenous fistula thrombosis is associated with increased all-cause and cardiovascular mortality in haemodialysis patients from the AURORA trial.

BackgroundThe impact of arteriovenous fistula (AVF) or graft (AVG) thrombosis on mortality has been sparsely studied. This study investigated the association between AVF/AVG thrombosis and all-cause and cardiovascular mortality.MethodsThe data from 2439 patients with AVF or AVG undergoing maintenance haemodialysis (HD) included in the A Study to Evaluate the Use of Rosuvastatin in Subjects on Regular Hemodialysis: An Assessment of Survival and Cardiovascular Events trial (AURORA) were analysed using a time-dependent Cox model. The incidence of vascular access (VA) thrombosis was a pre-specified secondary outcome.ResultsDuring follow-up, 278 AVF and 94 AVG thromboses were documented. VA was restored at 22 ± 64 days after thrombosis (27 patients had no restoration with subsequent permanent central catheter). In multivariable survival analysis adjusted for potential confounders, the occurrence of AVF/AVG thrombosis was associated with increased early and late all-cause mortality, with a more pronounced association with early all-cause mortality {hazard ratio [HR] < 90 days 2.70 [95% confidence interval (CI) 1.83–3.97], P < 0.001; HR > 90 days 1.47 [1.20–1.80], P < 0.001}. In addition, the occurrence of AVF thrombosis was significantly associated with higher all-cause mortality, whether VA was restored within 7 days [HR 1.34 (95% CI 1.02–1.75), P = 0.036] or later than 7 days [HR 1.81 (95% CI 1.29–2.53), P = 0.001].ConclusionsAVF/AVG thrombosis should be considered as a major clinical event since it is strongly associated with increased mortality in patients on maintenance HD, especially in the first 90 days after the event and when access restoration occurs >7 days after thrombosis. Clinicians should pay particular attention to the timing of VA restoration and the management of these patients during this high-risk period. The potential benefit of targeting overall patient risk with more aggressive treatment after AVF/AVG restoration should be further explored.

Hybrid salvage of thrombosed dialysis access grafts.

To report our experience and evaluate the results of a hybrid procedure comprising of surgical thrombectomy and adjuvant high pressure balloon angioplasty for management of thrombosed arteriovenous grafts (AVGs) with underlying venous anastomotic stenosis. Between January 2015 and June 2017, 148 patients with first-time thrombosis of AVGs were considered for treatment with surgical thrombectomy followed by high pressure balloon angioplasty of the underlying venous anastomotic lesions. Monitoring and surveillance was subsequently performed using clinical and hemodialysis criteria to detect a failing/failed access. Primary, assisted primary, and secondary patency rates were calculated using Kaplan-Meier analysis. This hybrid procedure was technically successful in 135 cases (91.2%) and clinically successful in 131 cases (88.5%). The postintervention primary patency rate of the target lesions was 68.2%, 52.4%, and 44.2% at 3, 6, and 12 months, respectively. Endovascular re-interventions increased significantly the postintervention assisted primary patency to 79.1%, 71.9%, and 66.8% (P=0.0004), and the postintervention secondary patency to 86.5%, 82.2%, and 78.6% (P<0.0001) at the same time points, respectively. Hybrid salvage of thrombosed AVGs using high pressure balloon angioplasty of the venous anastomotic stenosis following surgical thrombectomy by Fogarty catheter is a highly successful and safe procedure, with acceptable short-term primary patency. The need for repeated interventions demonstrates the necessity of continuous graft monitoring and surveillance to improve both assisted primary, and secondary patency rates.

Safety and efficacy of the AngioJet device in the treatment of thrombosed arteriovenous fistula and grafts: A systematic review.

The AngioJet Hemolytic Thrombectomy Device "AngioJet" (Boston Scientific, Malborough, MA, USA) is a rheolytic thrombectomy device that can be used in the treatment of hemodialysis arteriovenous fistula and graft thrombosis. We aim to appraise the current evidence on AngioJet thrombectomy in hemodialysis vascular access thrombosis, and to determine its safety, including complications and efficacy. An electronic literature search was performed on the MEDLINE and Embase databases. References of retrieved articles were also reviewed. Articles using AngioJet for the treatment of arteriovenous fistula or graft were included. Patients less than 18 years old, non-English articles, single case reports, small case series (<5 cases), conference publications, and nonhuman models were excluded. A total of 688 articles were initially evaluated and 10 articles fulfilled the inclusion criteria, which included 836 patients with 431 grafts and 234 fistulas. Results were heterogeneously reported. The adjusted mean primary patency rates for 1, 3, 6, and 12 months were 64.6%, 43.8%, 42.5%, and 30.5%, respectively; adjusted mean secondary patency rates for 3, 6, and 12 months were 76.5%, 75.1%, and 74.5%, and assisted primary patency rates were 61.9%, 47.3%, and 35.3%, respectively. There were 126 complications, most were minor. There were seven deaths, but were unable to be attributable to the AngioJet. The AngioJet is an effective and safe treatment option for thrombosed fistulas and grafts. However, the quality of the current evidence is poor. Further research with prospective randomized controlled trials using standardized data reporting methods is needed to prove its safety and efficacy.