Forearm Arteriovenous Grafts Research Articles

Temporal trends in hemodialysis access creation during the fistula first era

ObjectiveAlthough forearm arteriovenous fistulas (AVFs) are the preferred initial vascular access for hemodialysis based on national guidelines, there are no population-level studies evaluating trends in creation of forearm vs upper arm AVFs and arteriovenous grafts (AVGs). The purpose of this study was to report temporal trends in first-time permanent hemodialysis access type, and to assess the effect of national initiatives on rates of AVF placement. MethodsRetrospective cross-sectional study (2012-2022) utilizing the Vascular Quality Initiative database. All patients older than 18 years with creation of first-time upper extremity surgical hemodialysis access were included. Anatomic location of the AVF or AVG (forearm vs upper arm) was defined based on inflow artery, outflow vein, and presumed cannulation zone. Primary analysis examined temporal trends in rates of forearm vs upper arm AVFs and AVGs using time series analyses (modified Mann-Kendall test). Subgroup analyses examined rates of access configuration stratified by age, sex, race, dialysis, and socioeconomic status. Interrupted time series analysis was performed to assess the effect of the 2015 Fistula First Catheter Last initiative on rates of AVFs. ResultsOf the 52,170 accesses, 57.9% were upper arm AVFs, 25.2% were forearm AVFs, 15.4% were upper arm AVGs, and 1.5% were forearm AVGs. From 2012 to 2022, there was no significant change in overall rates of forearm or upper arm AVFs. There was a numerical increase in upper arm AVGs (13.9 to 18.2 per 100; P = .09), whereas forearm AVGs significantly declined (1.8 to 0.7 per 100; P = .02). In subgroup analyses, we observed a decrease in forearm AVFs among men (33.1 to 28.7 per 100; P = .04) and disadvantaged (Area Deprivation Index percentile ≥50) patients (29.0 to 20.7 per 100; P = .04), whereas female (17.2 to 23.1 per 100; P = .03), Black (15.6 to 24.5 per 100; P < .01), elderly (age ≥80 years) (18.7 to 32.5 per 100; P < .01), and disadvantaged (13.6 to 20.5 per 100; P < .01) patients had a significant increase in upper arm AVGs. The Fistula First Catheter Last initiative had no effect on the rate of AVF placement (83.2 to 83.7 per 100; P=.37). ConclusionsDespite national initiatives to promote autogenous vascular access, the rates of first-time AVFs have remained relatively constant, with forearm AVFs only representing one-quarter of all permanent surgical accesses. Furthermore, elderly, Black, female, and disadvantaged patients saw an increase in upper arm AVGs. Further efforts to elucidate factors associated with forearm AVF placement, as well as potential physician, center, and regional variation is warranted.

The Natural History of Upper Arm Vessels After Placement of a Forearm Arteriovenous Graft: A Pilot Study

The Natural History of Upper Arm Vessels After Placement of a Forearm Arteriovenous Graft: A Pilot Study

Assessment of Proximal Radio-median Cubital/Radio-Cephalic Arterio-venous Fistula

The present study aims to conducted the Assessment of Proximal radio-median cubital/radio-cephalic Arterio-venous Fistula. Arterio-venous Fistula is life line for long-term hemodialysis for end stage renal disease patients. The order of preference as per National Kidney Foundation/ Kidney Disease Out Come Quality Initiative (KDOQI) is distal Radio Cephalic fistula is considered as gold standard followed by elbow Brachio Cephalic Fistula, transposed Brachio-Basilic Fistula, forearm arterio-venous graft. This is a cross sectional-prospective interventional study, 05/2017 to 04/2019, JNMC, Wardha, MH, with sample size of 66 cases. Out of 66 cases 25 % patients had diabetes mellitus, 48% cases were suffering from chronic glomerulonephritis, 15 % cases were suffering hypertension, 6 % cases had COPD and another 6 % cases had some cardiovascular disease. About 54 % cases had previous access failure. In our study the mean flow volume for AV fistula in proximal forearm was 485± 291 ml/minon postoperative day1, 695 ± 298 on postoperative day 7 and 755± 347 ml/min. Overall postoperative complications in 12% cases was reported in our case study though Yilmiz et al reported postoperative complications in 15% cases.

Hemodynamic Analysis on the Anastomosis Angle in Arteriovenous Graft Using Multiphase Blood Model

Numerical analysis was performed for the effect of the venous anastomosis angle in a forearm arteriovenous graft for hemodialysis using a multiphase blood model. The geometry of the blood vessel was generated based on the patient-computed tomography data. The anastomosis angles were set at 15°, 30°, and 45°. The hematocrit was set at 34%, 45%, and 58%. The larger anastomosis angle, high wall shear stress area &gt;11 Pa, increases to the side of the vein wall away from the anastomosis site. Further, the relatively low wall shear stress area, &lt;3 Pa, occurs near the anastomosis site in larger anastomosis angles. Therefore, the effect of high wall shear stress has advantages in the vicinity of the anastomosis, as the anastomosis angle is larger, but disadvantages as the distance from the anastomosis increases. Moreover, patients with low hematocrit are advantageous for WSS area.

Long-term patency and comparisons of venous outflow in hemodialysis forearm arteriovenous grafts.

This retrospective study investigated the factors and the effects of different venous outflows on forearm arteriovenous graft patency. The venous outflow sites included basilic, cephalic, median antecubital, and deep veins. Comparisons among multiple groups were analyzed. A total of 179 patients with forearm loop arteriovenous grafts met the inclusion criteria. Of these, 72 were basilic, 48 were cephalic, 44 were median antecubital, and 15 were deep. The median observation period was 19 months. The survival rate was 84.9% at 24 months and 78.2% at 48 months. Primary, secondary, and assisted primary patency rates for all arteriovenous grafts were 48.9%, 72.4%, and 68.4% at 12 months; 13.8%, 33.9%, and 23.6% at 24 months; and 0.6%, 4.6%, and 2.3% at 48 months, respectively. Differences in primary patency were statistically significant compared with those of secondary and assisted primary patency (P < 0.05). Primary patency rates for cephalic, median antecubital, basilic, and deep were 47.9%, 48.6%, 47.7%, and 40.0% at 12 months and 12.5%, 13.9%, 22.7%, and 0% at 24 months, respectively. Secondary patency rates for cephalic, median antecubital, basilic, and deep were 75.0%, 69.4%, 75.0%, and 73.3% at 12 months and 39.6%, 30.6%, 38.6%, and 13.3% at 24 months, respectively. There was no significant difference in primary thrombosis among basilic, cephalic, median antecubital and deep. There were no significant differences observed in primary or secondary patency rates among all the groups. Stenoses in the venous anastomosis and outflow vein were frequently observed in all types of arteriovenous grafts. Central venous stenosis was most commonly seen in deep (26.67%). On average, 1.9 interventions per patient were performed on the graft to maintain function. Different venous outflow selections were not associated with long-term patency and the occurrence of thrombosis in hemodialysis forearm loop arteriovenous grafts.

Outcome of Percutaneous Intervention in Dysfunctional Loop versus Straight Arteriovenous Grafts in Hemodialysis Patients.

Objective:To compare the patency control of dysfunctioning forearm arteriovenous graft (AVG) using percutaneous transluminal angioplasty (PTA) in patients with loop versus straight grafts.Materials and Methods:Between January 2012 and March 2017, hemodialysis patients with forearm AVG were treated with PTA at two hospitals. We reviewed technical and clinical success rates of each procedure. Procedure time and patency of the graft were compared for all patients as well as for subgroups of stenosis only and thrombosis using paired-sample t-test and Kaplan-Meier analysis.Results:Sixty-six patients (mean age, 62.11 ± 11.85 years) underwent PTA. Thirty-eight patients (58%) had loop grafts and 28 (42%) had straight grafts. Among 66 patients, 54 (82%) had thrombosis. Technical success rate was 95.5% (only stenosis: 100%; thrombosis: 94%) and the mean procedure time was 48.00 ± 16.75 minutes in all patients. Although there was a tendency towards shorter procedure time in patients with loop grafts (45.24 ± 20.24 minutes) than those with straight grafts (51.85 ± 22.76 minutes), the difference was not statistically significant (p = 0.217), with or without thrombi. There was no statistical significance in primary and assisted primary patency (log rank 0.78, p = 0.38 in primary patency; log rank 0.88, p = 0.35 in assisted primary patency).Conclusion:Our study suggests there is no different patency outcome between straight and loop arteriovenous grafts after PTA.

Upper Arm Arteriovenous Grafts are Superior over Forearm Arteriovenous Grafts in Upper Extremity Dialysis Access

In this study, we compared the outcomes of forearm arteriovenous grafts (AVGs) and upper arm AVGs in a large, prospectively collected data set, which represents real-world experience with upper extremity prosthetic dialysis access, to determine if there are clinically significant differences in the upper arm and forearm positions. We identified 2,063 patients who received upper extremity AVGs within the Vascular Quality Initiative data set (2010-2018). Axillary to axillary upper arm AVGs were excluded (n=394) from the analysis. The main outcome measures were primary and secondary patency rates at 12months. Other outcomes were 6-month wound infection, steal syndrome, and arm swelling. The log-rank test was used to evaluate patency loss using a Kaplan-Meier analysis. Cox proportional hazards models were used to examine adjusted association between locations (forearm and upper arm) and outcomes. There were 1,160 forearm AVGs and 509 upper arm brachial artery AVGs in the study cohort. Patients with forearm AVGs were more likely to have a body mass index>30 (45% vs. 38%, P=0.013), no history of previous access (73% vs. 63%, P<0.001), and underwent local-regional anesthesia (56% vs. 43%, P<0.001). The 12-month primary patency (51.5% vs. 62.9%, P<0.001) and secondary patency (76.4% vs. 89.1%, P<0.001) were significantly lower for forearm AVGs. Wound infection, steal syndrome, and arm swelling were similar between forearm AVGs and upper arm AVGs at the 6-month follow-up. In multivariable analysis, the primary patency loss (adjusted hazard ratio (aHR) 1.66, 95% confidence interval (CI) 1.33-2.01, P<0.001) and 12-month secondary patency loss (aHR 2.71, 95% CI 1.84-3.98, P<0.001) were significantly higher for forearm AVGs at 12months. From this observational study of the Vascular Quality Initiative data set, the primary and secondary patency rates were superior for upper arm brachial artery AVGs compared with forearm AVGs.

Upper Arm Arteriovenous Grafts Are Superior Over Forearm Arteriovenous Grafts in Upper Extremity Dialysis Access

The optimal location for placement of an upper extremity (forearm or upper arm) arteriovenous graft (AVG) is unknown. In this study, we compared the outcomes of forearm AVGs and upper arm AVG.

The Effect of Artery and Vein Size on Forearm Hemodialysis Arteriovenous Graft Patency.

Objective: Arteriovenous grafts (AVGs) are considered to be an alternative procedure when autogenous fistulas are not feasible. This study was conducted to establish a correlation between the inflow artery and outflow vein size and patency of AVGs.Materials and Methods: This was a retrospective descriptive study. Data was collected from patients who had forearm AVG performed at a university hospital from January 1, 2012, to December 31, 2016. Spearman’s rho correlation test was used to identify the correlation between the artery and vein size and patency of AVG.Results: A total of 34 patients were enrolled in this study. Forearm loop configuration was performed in 33 patients (97%), and straight configuration was performed in one patient (3%). The median size of the brachial artery was 3 mm (interquartile range [IQR]: 2, 4) and that of the vein was 3 mm (IQR: 2, 5). The overall primary patency was 74% at six months, 59% at one year, and 32% at two years. The analysis showed that the primary patency increased with the artery size, but there was a reverse correlation between vein sizes.Conclusion: Small inflow arteries may reduce the primary patency, but small veins do not result in a poor primary patency. Our method can be applied to patients with small veins, where it is still possible to perform forearm AVGs.

The forearm arteriovenous graft between the brachial artery and the brachial vein as a reliable dialysis vascular access for patients with inadequate superficial veins

ObjectiveThe arteriovenous fistula (AVF) is recommended as the preferred hemodialysis access. However, placing an AVF in all patients may result in poor access outcomes and increased central venous catheter (CVC) use because of increased comorbid conditions, age, and suboptimal vessels. In patients with inadequate superficial veins for AVFs, the use of the brachial veins for creation of forearm arteriovenous grafts (AVGs) has received limited attention. This retrospective study aimed to evaluate outcomes of forearm brachial-brachial AVGs (BB-AVGs) placed in patients with poor superficial veins. MethodsWe identified 111 BB-AVGs created in 111 consecutive patients, using standard-walled polytetrafluoroethylene grafts, between January 2010 and December 2015. After excluding 6 patients (non-dialysis initiation, missing information, and death within 1 month), we included 105 patients from 21 dialysis centers. We analyzed primary failures, time to cannulation, patency, complications, and revisions. Patency rates were calculated by the Kaplan-Meier method. The incidence of complications and revisions was expressed as number of events per person-year. ResultsA total of 105 patients (median age, 69 years) were followed up for a median time of 21.2 months (interquartile range, 9.2-36.5 months). Of the patients, 72.4% were on chronic hemodialysis and had previously undergone one or more access procedures. At the time of BB-AVG placement, prior accesses were 39 AVFs, 20 tunneled CVCs, and 17 AVGs. BB-AVG rates of primary failure and revision before cannulation were 7.6% and 5.7%, respectively. BB-AVGs were cannulated after a median time of 3.4 weeks (interquartile range, 2.8-4.1 weeks). Primary patency rates at 12, 24, and 36 months were 49.5%, 29.5%, and 19.5%. Secondary patency rates at 12, 24, and 36 months were 76.3%, 62.7%, and 54.6%. After cannulation, the incidence of complications and revisions was 1.054 and 0.649 per person-year, respectively. Most complications and interventions were due to thrombosis (0.527 per person-year) or stenosis (0.381 per person-year) and related interventions (0.490 per person-year). A minority of patients experienced AVG infections (0.052 per person-year), with only two requiring access removal. ConclusionsIn patients with poor superficial veins, the forearm BB-AVG is a reliable access because of low access-related morbidity and considerable long-term access survival. BB-AVG placement has the advantage of preserving proximal vessels. In these patients, such an approach can delay both rapid exhaustion of vascular sites and early recourse to CVC permanent use.

Comparison of Forearm Swelling After Loop Forearm Arteriovenous Graft between Distal Vein Ligation and No Ligation

PurposeForearm loop arteriovenous grafts (AVGs) are an effective way to grant permanent vascular access in end-stage renal disease patients undergoing hemodialysis. A common postoperative complication with this procedure is forearm swelling. Distal vein ligation is believed to reduce postoperative venous hypertension and forearm swelling. There have been no previous randomized controlled trials comparing the efficacy of AVGs with and without distal vein ligation. MethodsA pilot study was performed as a randomized controlled trial. End-stage renal disease patients who required AVG construction were recruited and randomly assigned to either the distal vein ligation group or the nondistal vein ligation group. Forearm swelling, graft patency, and graft thrombosis were recorded and compared. ResultsThe nonligation and ligation groups consisted of 30 and 31 patients, respectively. Forearm swelling at both the proximal and distal areas was nonsignificantly higher in the nonligation group than in the ligation group. The success rate of cannulation of the graft was 77% in both groups. The first cannulation time was somewhat shorter in the ligation group than in the nonligation group (57 vs 63 days; P = .282). There was no difference in graft thrombosis between the 2 groups (8 and 6 patients, respectively, in the nonligation and ligation groups). ConclusionsAVGs can be performed with or without distal vein ligation.

Forearm versus upper arm grafts for vascular access.

Forearm and upper arm arteriovenous grafts perform similarly in terms of patency and complications. Primary patency at 1 year for forearm arteriovenous grafts versus upper arm grafts ranges from 22%-50% versus 22%-42%, and secondary patency at 1 year ranges from 78%-89% versus 52%-67%), respectively. Secondary patency at 2 years, ranges from 30%-64% versus 35%-60% for forearm and upper arteriovenous graft, respectively. Ample pre-operative planning is essential to improved clinical success and the decision to place a graft at one location versus the other should be based solely on previous access history, physical exam, appropriate venous imaging, and other factors that make up the clinical picture. Operative implant strategies and risk of complications are very similar between the two configurations. Postoperative ischemia due to steal syndrome is a potential complication that requires immediate attention. Utilization of the proximal radial or ulnar artery for inflow for the graft can minimize risk of clinically relevant steal syndrome.

Feasibility and Safety of Coronary Procedures via an Arteriovenous Graft Approach in Patients on Maintenance Hemodialysis.

Traditionally, a radial or brachial arterial approach is unadvisable in hemodialysis patients. Consequently, coronary angiography or angioplasty is usually performed via a femoral artery approach in these patients, who carry a higher risk of vascular access complications. In hemodialysis patients, arteriovenous grafts (AVG) are created for repeated punctures; however, the feasibility and safety of a trans-AVG approach for coronary angiography or angioplasty remains unclear. In our institution, cardiac catheterizations were attempted via AV grafts in hemodialysis patients with a U-shaped forearm AVG. We retrospectively identified coronary angiography or angioplasty procedures in hemodialysis patients from a computer-based database in our hospital. The procedure details and outcomes were obtained from review of the clinical, angiographic and hemodialysis records. From 2008 to 2013, 167 procedures in hemodialysis patients were identified from 2866 diagnostic or interventional coronary procedures in our institution. Out of these, 24 procedures in 17 patients were performed via a trans-AVG approach. In all AVG procedures, a 6F 16-cm or 7F 10-cm sheath was placed from the AVG into the brachial artery. All diagnostic procedures were successfully performed. In 14 procedures, the patients also underwent angioplasty and all of the angioplasty procedures were successful. There was no arterial spasm, arterial dissection, puncture site hematoma, or acute thrombosis of the AVG during or after the procedures. A trans-AVG approach appears to be a feasible and safe route for coronary angiography or angioplasty in hemodialysis patients with a U-shaped forearm AVG. However, further studies with a larger patient number are necessary. Arteriovenous graft; Hemodialysis; Percutaneous coronary intervention.

Vascular access graft thrombosis by iatrogenic fistula

AbstractProsthetic arteriovenous graft thrombosis is multifactorial and includes stenosis of the graft‐venous and graft‐arterial anastomosis, excessive compression for hemostasis at the end of dialysis, complication of dialysis needle placement, hypotension, hypovolemia, and hypercoagulable states. We report a case of arteriovenous graft thrombosis resulting from a traumatic fistula between an arteriovenous graft and the adjacent basilic vein related to repeated cannulation. A 49‐year‐old female with end‐stage renal disease visited our department with a thrombosed left forearm arteriovenous graft. On physical examination, there was strong pulsation on the arterial limb of the graft, but no thrill and bruit on the venous limb. Fistulography was performed for endovascular treatment of the arteriovenous graft thrombosis. However, it showed a fistula arising from the dialysis graft and communicating with the adjacent basilic vein. The purpose of this discussion is to highlight a rare cause of vascular access graft thrombosis including etiology, pathophysiology, diagnosis, prevention, and treatment.

Evaluation of the efficacy of the forearm basilic vein transposition arteriovenous fistula

Since the publication of Dialysis Outcomes Quality Initiative (DOQI) guidelines, the use of native veins for the construction of arteriovenous fistulas (AVF) for hemodialysis has been highly recommended rather than prosthetic arteriovenous grafts (AVG). Upper arm basilic vein transposition (BVT) has been accepted widely, with superior patency compared with AVG, but only a few studies have reported outcomes of forearm BVT (FBVT). This study evaluated the efficacy of FBVT compared with direct AVF (DAVF) and AVG in a tertiary referral center. From January 2005 to December 2007, 461 patients underwent AV access for hemodialysis in Seoul National University Hospital. We retrospectively reviewed the medical records and dialysis sheets and evaluated the current AVF function in the outpatient clinic or by telephone interviews. Patients were grouped by the operation type: DAVF, FBVT, and AVG. The outcomes compared were primary, assisted-primary and secondary patency rates, maturation failure, and complications. The mean age was 59 years (range, 14-92 years), and 280 patients (60.7%) were male. By operation type, the 461 accesses were 389 DAVF (84.4%), 34 FBVT (7.4%), and 38 AVG (8.2%). Mean follow-up duration was 21 months (range, 1-51 months). The primary patency rates for DAVF, FBVT, and AVG were 67.6%, 41.5%, 35% at 12 months and 53.9%, 30.2%, 10.3% at 24 months, respectively. The secondary patency rates were 89.2%, 79.1%, 78.3% at 12 months and 83.8%, 74.4%, 64.9% at 24 months, respectively. Maturation failure occurred in five DAVF patients and in one FBVT patient. The infection rate was 0.3% in DAVF and 12.5% in AVG, but no infection occurred in patients with FBVT. Multivariate analysis revealed that age and history of previous access were associated with lower primary patency. Forearm BVT showed an acceptable, high 2-year patency rate and fewer thromboses and infectious complications than AVG. Forearm BVT could be considered before forming an upper arm AVF or forearm AVG, if the basilic vein is available.

Biting Through an Arteriovenous Hemodialysis Graft: An Unusual Method of Suicide

Patients on long-term hemodialysis often have multiple medical and social problems with associated psychological stress and depression. The suicide rate in this population is higher than the general population, and suicides have been reported following severing or disconnection of hemodialysis vascular access sites. We report a patient on chronic hemodialysis with a history of depression and suicidal ideation who bit into his forearm arteriovenous graft and exsanguinated.

Brachial artery ligation with total graft excision is a safe and effective approach to prosthetic arteriovenous graft infections

While autogenous arteriovenous access is preferred, prosthetic arteriovenous grafts (AVG) are still required in a large number of patients. Infection of AVGs occurs frequently and may cause life-threatening bleeding or sepsis. Multiple treatment strategies have been advocated (ranging from graft preservation to excision with complex concomitant reconstructions), indicating a lack of consensus on appropriate management of infected AVGs. We undertook this study to evaluate if, in the setting of anastomotic involvement, brachial artery ligation distal to the origin of the deep brachial artery accompanied by total graft excision (BAL) is safe and effective. All prosthetic arteriovenous graft infections managed by a single surgeon between 1995 and 2006 were reviewed retrospectively. Patients were identified from a computerized vascular registry, and data were obtained via patient charts and the electronic medical record. We identified 45 AVG infections in 43 patients. Twenty-one patients (49%) demonstrated arterial anastomotic involvement and were treated with BAL; these form the cohort for this analysis. Mean patient age was 53.2 (SD 9.5) years. The primary etiologies for end stage renal disease (ESRD) were hypertension (29%), HIV (24%), and diabetes (19%). An upper arm AVG was present in 95% of patients; one (5%) had a forearm AVG. The majority of grafts were polytetrafluoroethylene (PTFE) (90%). Follow-up was 100% at 1 month, 86% at 3 months, and 67% at 6 months. No ischemic or septic complications occurred in the 21 patients who underwent BAL. BAL is an effective and expeditious method to deal with an infected arm AVG in frequently critically ill patients with densely scarred wounds. In the short term, BAL appears to be well tolerated without resulting ischemic complications. Further study with longer duration of follow-up is necessary to ascertain whether BAL results in definitive cure, or whether patients may ultimately manifest ischemic changes and require additional intervention.

Massive Upper GI Bleeding in a Long-term Hemodialysis Patien

(CHEST 2005; 128:1868–1873) A 55-year-old diabetic, hypertensive man receiving long-term hemodialysis presented to the emergency department with a complaint of two episodes of lightheadedness, the last being on the morning of hospital admission while straining at stool. He denied having lost consciousness at any time. The patient had been dialysis dependent for the last 5 years and had recurrent episodes of arteriovenous graft thrombosis requiring revisions, with recent placement of a right internal jugular hemodialysis catheter 2 weeks ago after removal of a left internal jugular vein hemodialysis catheter. His diabetes and hypertension were poorly controlled, and he had recently been switched from oral medications to insulin. A review of systems did not reveal any history of conduction abnormalities, heart failure symptoms, or previous ischemic events, but was significant for both resting and exertional dyspnea for the last 1 week. Physical Examination The patient was afebrile and hemodynamically stable (BP 150/60 mm Hg) with no orthostasis: pulse rate, 76 beats/min; normal sinus rhythm; pulse oxygen saturation, 96% on room air; and no acute distress. The examination was significant for neck vein engorgement, a right subclavian hemodialysis catheter, and a clotted left forearm arteriovenous graft. His right forearm arteriovenous fistula was functioning with a palpable bruit. Laboratory Data

The effect of a venous anastomosis Tyrell vein collar on the primary patency of arteriovenous grafts in patients undergoing hemodialysis

Purpose: Vein collars and patches are used at the distal anastomoses of infrainguinal prosthetic grafts to improve graft patency. We initiated a randomized, prospective study to determine whether a Tyrell vein collar at the venous anastomosis of forearm loop arteriovenous grafts (AVGs) would improve patency. Methods: Patients who required new forearm AVGs were randomized to (1) a standard end-to-side graft-vein anastomosis (control group) or (2) a Tyrell vein collar between the graft and the vein (study group). End points were (1) graft thrombosis, (2) graft removal and ligation, or (3) inadequate graft function. Randomization of 75 subjects was planned. The study was terminated early for ethical reasons. Results: Seventeen patients (eight men, nine women) with a mean age of 52.8 years (range, 31-79 years) had 17 grafts placed (control group, n = 10; study group, n = 7). Comorbidities were not different between the groups (P >.05). Six (86%) of seven study grafts failed by 9 months (mean, 4.6 months). Four (66%) failed study grafts had venous outflow tract stenosis from intimal hyperplasia. This was confirmed at surgery in three and by angiography in one. The 9-month primary patency was 80% for the control group versus 17% for the study group (P =.015). Smaller outflow vein diameter in the study group (P =.048) did not account for this inferior graft patency. Conclusion: A Tyrell vein collar at the venous anastomosis of a forearm AVG resulted in premature graft failure. The use of a Tyrell vein collar may accelerate venous anastomosis intimal hyperplasia. (J Vasc Surg 2000;32:1149-54.)

Antecubital Jump Revisions for Salvaging Hemodialysis Grafts

When expanded polytetrafluoroethylene (PTFE) is used for hemodialysis access, the authors' initial preference is a forearm loop arteriovenous (AV) graft below the antecubital fossa. However, AV graft thrombosis remains a significant problem caused mainly by venous outflow hyperplasia and managed often by either surgical or radiologic thrombectomy and angioplasty. At the time of surgical revision, the lack of an adequate superficial or deep forearm outflow vein below the elbow would require an antecubital (across the elbow) jump bypass revision to a more proximal upper arm vein to salvage the original forearm AV graft. With an increasing interest in monitoring the specific outcomes of the different surgical interventions used to salvage thrombosed hemoaccess, the authors reviewed their most recent 24--month experience of 32 antecubital jump revisions using ring reinforced PTFE. The mean primary patency of these antecubital jump revisions was 8.2 months with 18 presently patent. AV grafts revisions using antecubital jump grafts confer additional patency; they are another important method for salvaging thrombosed AV hemodialysis grafts.