Latis™ Catheter: New Technology for Thrombectomy of Vascular access Grafts

Purpose The most common complication of vascular access surgery is thrombosis. This study compared the gold standard Fogarty Thrombectomy Catheter, to the new latis Catheter with an advanced monofilament matrix. Methods 30 patients with thrombosed access grafts were randomly assigned to undergo thrombectomy with the Fogarty or latis catheter. An angioscope measured remaining graft thrombi. Results Twenty-nine of 30 subjects were successfully thrombectomized. No statistical differences in age, gender, race, or extension graft requirements were found. Catheter use in the latis group was: 1 in 14 procedures, and 2 in 1 procedure; Fogarty group: 1 in 10 procedures, 2 in 3 procedures, and 3 in 2 procedures. The average number of catheter passes was: latis 3.06 (1–6 passes) and Fogarty 4.13 (1–9 passes). A trend in favor of the latis catheter was demonstrated; however, statistical significance was not reached (p = 0.067). The overall 6-month primary patency rates were latis (40%) and Fogarty (30%). The estimated patency at the 50th percentile for latis is 120 days and Fogarty 108 days. Statistical significance was not reached with a p-value of the Log-Rank statistic of 0.68 and a p-value of the Wilcoxon statistic of 0.78. Conclusions The latis and Fogarty catheters are very similar. However, the latis balloon is more rugged with fewer catheters used and reduced number of passes. A difference in primary patency could not be demonstrated. The angioscope identified significant residual thrombus despite no returning thrombus from the catheter. Consequently, our protocol is modified to include the angioscope

New Graft for Low Friction Tunneling in Vascular Access Surgery

Purpose Prosthetic accesses of the upper extremity have been in use for more than 25 years. Many different conduits have been employed; investigators have continually searched for a graft with superior properties. Methods We describe a prospective randomized study comparing the new Slider Graft (Atrium) with the Hybrid PTFE Graft (Atrium); the latter has been used for a number of years. The Slider Graft is also made of PTFE. For this study, both grafts were 6 mm in diameter and 40 cm in length. The Slider Graft has a low friction polyethylene sheath over its entire length. This sheath expedites the passage of the graft through the tunnel. At one end, the graft and the polyethylene sheath are attached to a metal tip. This tip has male threads, which may be inserted firmly into a Kelly Wyck, Atrium, or any standard non-sheath tunneling system. This alleviates graft separation, turning, and slipping during tunneling. The primary objective of this trial was to determine the safety and efficacy of the Slider Graft as compared to the Hybrid Graft in vascular access surgery. The secondary objective was to evaluate how tunneling effects graft performance. We randomized 60 subjects for this study with two equal arms. During surgery we measured various parameters including ease of tunneling, tunnel bleeding, anastomotic bleeding, graft sweating, and immediate patency. To assess arm edema we measured circumference 7.5 cm and 20 cm above the wrist, prior to surgery and in follow-up visits at 1 week, 1 month, and 3 months. Primary patency was also assessed at these visits and at 6, 9, and 12 months. Results Our results show tunneling with the Slider Graft is easier to accomplish (p = 0.0001) with reduced tunnel bleeding (p = 0.0047) and anastomotic bleeding (p = 0.042). Further, the Slider Graft virtually eliminated the complication of graft sweating and seroma development (p = 0.0005). This may be due to reduced stretching and graft wetting during insertion. At 180 days the Slider Graft demonstrated improved primary patency, which was statistically significant (p = 0.047). At 360 and 720 days the Slider Graft continued to demonstrate a trend toward improved primary patency (p = 0.160). Conclusions This study suggests the Slider Graft has significant advantages when compared to the Hybrid Graft and highlights the importance of tunneling in creating prosthetic accesses

Arteriovenous Fistulae vs. Arteriovenous Grafts: A Retrospective Review of 1,700 Consecutive Vascular access Cases

Objective Vascular access (VA) procedures are rapidly becoming the most prevalent surgery in the United States. It is estimated that there will be over 500,000 VA procedures done this year. Previously, surgeons in the US were attempting many more non-autogenous grafts than autogenous fistulae. In recent years, there has been a great push called “Fistula First” to promote arteriovenous fistulae (AVF) as the first line of treatment vs. non-autogenous grafts. The goal of this investigation is to determine if too many fistulae are now being performed without attention to specific patient profiles. Methods A retrospective review of 1700 consecutive cases was performed by one surgeon at one institution between 1997 and 2005. Patients were categorized by demographics, co-morbidities, previous access procedures, access location, and type of graft. Patency was calculated. Kaplan-Meier, Cox regression and the Log Rank Test were used to analyze data. Access endpoints and complications were also documented. Results The study reviewed 1700 procedures. The median age was 52 (60.2% male) with 58.7% fistulae and 41.3% grafts. Median patency time was 10 months, with no statistically significant difference between access types. There was no significant difference in length of patency when comparing upper arm (70.1%), lower arm (24.5%) and thigh (5.4%). Graft infection rate was 9.5% and fistula infection rate was 0.9% (p&lt;0.001). The overall infection rate was 4.5%, and decreased patency significantly (4 vs. 11 months). Thrombosis occurred in 24.7% of grafts and 9.0% of fistulae. Thrombosed grafts had better salvage rates (8 vs. 4 months, p&lt;0.001). The data showed diabetes, HTN and HIV have no overall impact on patency. Conclusions AVF and grafts are both useful in providing VA for patients requiring hemodialysis. Our data shows that grafts are equivalent in long-term patency. Therefore, it is apparent in those patients who are not candidates for an AV fistula; an AV graft for VA should be placed. </jats:sec