To the editor:
The internal native arteriovenous fistula (IAVF) is the elective vascular access in patients with chronic renal failure on hemodialysis.1 In case that the performance of a native access is impossible due to difficulties with the vascular bed, the vascular grafts constitute an efficacious alternative.2
The new polyurethane-urea prosthesis of the VECTRA type has a stiffer wall than those composed of polytetrafluorethylene (PTFE).3-5 This characteristic allows using it within the first days after placement, avoiding so the use of temporary catheters and their potential complications.6-8
In the last two years the VECTRA prosthesis have been employed in our Hemodialysis Unit in those patients with absent or difficult vascular access, who needed hemodialysis in the short term. We briefly describe our experience with the use of this type of vascular prosthesis, as well as their main characteristics, the evolution and the complications associated to their use.
Between January of 2005 and March of 2007 a total of 7 VECTRA prosthesis were placed in 6 patients (50% males), mean age 56.1 years and mean time on hemodialysis 98.6 months. The most frequent etiology of the ESRD was diabetes mellitus in 2 patients (33%). Other underlying conditions were high blood pressure (100%), ischemic heart disease and peripheral vascular disease (66%), and diabetes (33%). Mean Charlson¿s index was 7. In each patient the mean number of previous vascular access was 4.2 (32% IAVF, 32% temporary catheters, 20% funneled catheters, and 16% PTFE prosthesis). VECTRA prostheses were mainly placed at the femoral level in 42% of the cases. Mean time for the first puncture was 10.4 days, and the initial puncture was performed within the first 96 hours of graft placement in 58% of the cases. The following complications were registered: one serious hematoma during initial puncture, 6 thromboses of the prosthesis (85%), in 3 patients being immediate (first 7 days), and 1 pseudoaneurysm (14%) as a late complication. A surgical thrombectomy was performed that was effective, and 2 temporary catheters were placed to treat the complications. Only one prosthesis works to date, the mean working time of the thrombosed grafts being 30.5 days (5 cases). One patient received a renal transplant from a cadaver donor, which is still functioning, and during the study period 5 patients died from causes not related to the vascular access.
In our limited experience, the use of VECTRA type prosthesis allowed hemodialysis within the first days after placement in more than half of the cases, but early thrombosis was the most important complication with this type of prosthesis. With these results, the placement of these grafts should be limited to patients with no native IAVF because of difficult vascular accesses, who require not urgent shortterm renal replacement therapy.
