Secondary Functional Patency Research Articles

Radiocephalic and brachiocephalic arteriovenous fistula outcomes in the elderly

A recent meta-analysis has suggested that patients aged >65 have worse outcomes with radiocephalic arteriovenous fistulas (RCAVFs) compared with brachiocephalic arteriovenous fistulas (BCAVFs). We hypothesized that outcomes in patients aged > or = 80--a rapidly expanding cohort within this elderly group--might be skewing the results, and that age >65 may not be a contraindication to RCAVF formation. This study examined the effect of age group (<65, 65 to 79, >or =80) on functional outcomes (use; primary and secondary functional patency) in RCVAFs and BCAVFs. We identified the outcomes of all patients undergoing a first surgical access procedure for a RCAVF or BCVAF between January 1, 2000, and December 31, 2005. We examined the effect of age and other factors including sex, diabetes mellitus, hypertension, late referral (<3 months before dialysis), dialysis before surgical access, preoperative duplex ultrasound imaging, and ethnicity on non-AVF use and primary and secondary functional AVF patency. Logistic regression and Cox proportional hazards regression models were used. From a total of 658 patients, 361 had a RCAVF, and 297 had a BCAVF. Their median age was 68.5 years (interquartile range [IQR], 54.4 to 76.5 years), and 288 (43.8%) were aged <65 years, 274 (41.6%) were 65 to 79, and 96 (14.6%) were > or =80. Age did not influence the site of the first surgical access (P = .874). Only 85.7% of patients actually progressed to hemodialysis, and the RCAVF or BCAVF in 45.7% of those was never used for dialysis. Female sex (hazard ratio [HR], 2.24; 95% confidence interval [CI] 1.387 to 3.643; P = .001) was the only factor associated with an increase risk of RCAVF nonuse, whereas diabetes (HR, 2.095; 95% CI, 1.261 to 3.482; P = .004) was the only factor associated with an increase risk of BCAVF nonuse. The respective primary patency rates at 1 and 2 years for RCAVFs were 46.0% and 27.1% for patients <65, 47.0% and 36.0% for those 65 to 79, and 45.7% and 38.1% for those >or =80. Only female sex (HR, 1.679; 95% CI, 1.261 to 2.236; P = .001) and prior hemodialysis (HR, 1.363; 95% CI, 1.0.29 to 1.804; P = .031) were associated with loss of patency of RCAVFs. The primary functional patency rates for BCAVFs at 1 and 2 years were 39.3% and 31.0% for those <65 years; 53.30% and 37.5% for those 65 to 79, and 46.3% and 42.6% for those >or =80. No factors analyzed were associated with loss of primary functional patency of BCAVFs. Age did not affect usability, primary or secondary patency of either RCAVFs or BCAVFs. Although patient selection is important, even patients > or =80 years who are considered suitable for surgical placement of access should not be denied a RCAVF solely because of age.

Results of aggressive graft surveillance and endovascular treatment on secondary patency rates of Vectra Vascular Access Grafts

The aim of the present study was to determine the effect of an aggressive graft surveillance and endovascular treatment protocol on secondary patency rates of a polyetherurethaneurea vascular access graft, specially designed to provide early access and rapid hemostasis. One hundred and ninety Vectra Vascular Access Grafts (C. R. Bard, Inc, Murray Hill, NJ) were placed in 176 patients (78 females and 98 males, mean age 61.7 years). There were 41 forearm grafts, 145 upper arm grafts and four thigh grafts. Graft surveillance was performed by using clinical and hemodialysis parameters to detect a failing/failed graft and followed by endovascular treatment, rheolytic thrombectomy (AngioJet, Possis Medical Inc, Minneapolis, Minn) and/or angioplasty +/- stenting of the anatomical lesion (arterial anastomosis, graft, venous outflow, draining or central veins). Hemodialysis started after a median of 15.5 days, as soon as from the day of the operation in some cases. Bleeding complications occurred in six patients (3.2%), venous hypertension in seven (3.7%), steal syndrome in two (1.1%), neurological complications in two (1.1%), while late infection (range 2.7-14.6 months) was seen in six patients (3.2%). Thrombectomy and angioplasty (median number of sessions 1, interquartile range 1-2) was performed in 43 grafts. Isolated angioplasty, not associated with thrombosis (median number of sessions 1, interquartile range 1-2), was performed in 50 grafts. These interventions increased primary assisted patency from 69% and 63% at 12 and 18 months, respectively to a secondary patency rate of 86%. Taking into account grafts removed for late infection, functional secondary patency rate dropped to 83% and 81%, at 12 and 18 months, respectively. Arterial anastomosis angioplasty was performed more frequently in thrombosed grafts (28.6%) than failing grafts (6.7%), P < .001 and had a significant negative predictive value on secondary patency rates at 12 and 18 months, which were 60.5% compared with 89% for grafts that had no interventions performed (P = .007) and 90.9% for grafts that had any intra-graft, venous outflow, or draining or central vein stenosis treated with angioplasty at any stage (P = .002). Multivariate analysis identified the presence of arterial anastomosis stenosis as the single predictor of secondary patency (relative risk 0.247, P = .002). Aggressive graft surveillance and endovascular treatment increases significantly secondary patency rates of Vectra Vascular Access Grafts. Longer follow-up will determine the effectiveness of this policy. The role of inflow stenosis on graft longevity and alternative treatment options warrant further investigation.

Prosthetic thigh arteriovenous access: outcome with SVS/AAVS reporting standards.

Differences in the reporting methods of results for arteriovenous (AV) access can dramatically affect apparent outcome. To enable meaningful comparisons in the literature, the Society for Vascular Surgery and the American Association for Vascular Surgery (SVS/AAVS) recently published reporting standards for dialysis access. The purpose of the present study was to determine infection rates, patency rates, and possible predictive factors for prosthetic thigh AV access outcomes with the reporting standards of the SVS/AAVS. A retrospective analysis was performed of all patients who underwent placement of thigh AV access by the Surgical Teaching Service at Greenville Memorial Hospital between 1989 and 2001. Outcomes were determined based on SVS/AAVS Standards for Reports Dealing with AV Accesses. The rate of revision per year of access patency was also determined; this end point more accurately reflects the true cost and morbidity associated with AV access than do patency or infection rates alone. One hundred twenty-five polytetrafluoroethylene thigh AV accesses were placed in 100 patients. Nine accesses were excluded from the study, six because there was no patient follow-up and 3 as a result of deaths unrelated to the access procedure and which occurred less than 30 days after access placement. There were six (4%) late access-related deaths. There were 18 (15%) early access failures, related to infection in 14 cases (12%), thrombosis in three cases (2%), and steal in one case (1%). Early failure was more common in patients with diabetes mellitus (P =.036). The primary and secondary functional patency rates were 19% and 54%, respectively, at 2 years. Infection occurred in 48 (41%) accesses. The patency and infection rates were not influenced by patient age, gender, body mass index, or diabetes mellitus. The median number of interventions per year of access patency was 1.68, and this outcome was positively correlated with body mass index (P <.001). Prosthetic AV access in the thigh is associated with higher morbidity compared with that reported for the upper extremity, and should be considered only if no upper extremity AV access option is available. Early access failure and the requirement for an increased number of interventions to reestablish and maintain access patency are more common in patients with diabetes mellitus and obesity. The number of interventions per year of access patency is a valuable end point when assessing the outcome of AV access procedures.

A new operation with inadequate Brescia fistulae for preservation of more proximal veins

Purpose: The purpose of this study was to test the hypothesis that venous outflow of a Brescia fistula that is patent but unusable for one of a variety of reasons can provide adequate drainage to sustain a prosthetic arteriovenous graft based on the brachial artery, thus sparing more proximal veins for future access procedures. Methods: The operation consists of placement of a prosthetic graft between the brachial artery in the antecubital space and the cephalic vein at the wrist. Results: Between December 1998 and November 1999, 14 patients (eight male and six female; age range, 34 to 73 years; mean age, 51 years) underwent the operation. The original fistulae had been in place for 5 to 27 months (mean, 13 months). Thirteen grafts were patent at 30 days; the one early failure (24 days) was caused by infection. As of May 31, 2001, four grafts were being used (18 1 2 , 20, 23, and 28 months after placement) and four had been withdrawn in a functional state because of death (n = 3) or transplantation (n = 1). Primary functional patency rate with life-table analysis was 71%, 57%, 41%, and 41% at 3, 6, 9, and 12 months; secondary functional patency rate was 86%, 78%, 52%, and 52% at these same intervals. Three grafts had primary functional patencies greater than 18 months. Conclusion: Patent but unusable Brescia fistulae can provide adequate outflow to sustain arteriovenous grafts, thus sparing more proximal veins for future access procedures. The operation can extend by months or years the time during which satisfactory vascular access can be maintained in these patients, potentially increasing survival in some cases. We hope that the availability of this salvage option will encourage vascular surgeons to attempt arteriovenous fistulae at the wrist even in patients with suboptimal venous anatomy. (J Vasc Surg 2002;36:346-50.)