Bovine Carotid Artery Biologic Graft and Expanded Polytetrafluoroethylene for Permanent Hemodialysis Access

Bovine Carotid Artery Biologic Graft and Expanded Polytetrafluoroethylene for Permanent Hemodialysis Access

A Prospective Randomized Study of Bovine Carotid Artery Biologic Graft and Expanded Polytetrafluoroethylene for Permanent Hemodialysis Access

The investigators propose a randomized study to compare bovine carotid artery (BCA) biologic grafts and expanded polytetrafluoroethylene grafts (ePTFE) for permanent hemodialysis access.

Arteriovenous grafts (AVG) remain reliable substitutes for permanent hemodialysis access in scenarios that preclude the placement of arteriovenous fistulae. There is scarcity of evidence to support the current preference of synthetic conduits over biologic grafts in clinical practice. Advances in the design of AVG's warrant contemporary comparisons between synthetic and biologic AVG options. This is especially important as biologic conduits may confer an advantage by virtue of their inherent similarity to the native human vasculature. The overall goal of this project is to compare one and two year patency (functional, primary, primary assisted and secondary), complication rates and re-intervention rates between BCA and standard ePTFE grafts. The investigators hypothesize that vascular patient who will receive the BCA graft will have improved patency as well as lower complication and re-intervention rates compared to the standard ePTFE graft.

Patients will undergo surgery as per standard of care and receive the randomized graft in compliance to National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines for Arteriovenous graft creation. Surgeries will be elective in nature. The grafts will be placed either in the arm (brachial artery-axillary vein) or forearm (brachial artery to cephalic or suitably sized vein) based on anatomic suitability

The study will not be blinded because patient side blinding is expected to have minimal to no effect, while physician side blinding is impractical; and difficult to achieve due to the primary surgeon being the one usually who follows up on any intervention or treatment.

The ePTFE grafts used are the Flixene (Maquet-Atrium Medical, Hudson, NH), Advanta VXT (Maquet-Atrium), GORE-TEXStretch Vascular Graft For Vascular Access (W. L. Gore and Associates, Flagstaff, Ariz), or Venaflo (Bard Peripheral Vascular, Tempe, Ariz). The choice of graft used is at the surgeons' discretion. The graft it is offered in both large and small diameters, as well as thin-wall and rapidly-tapering designs for cases where arterial steal syndrome is a potential complication. A 6 mm graft featuring external supporting rings in 5 cm centered or 7 cm offset sections enables tight loop configurations and crossing the cubitus. A 4-7 mm tapered graft with 10 or 15 cm of removable rings allows for tailoring or exact placement of the ringed section.

The bovine carotid artery biological grafts (Artegraft®; Artegraft, Inc., North Brunswick, NJ) consist of a biological fibrous matrix processed to enhance long-term patency and provide a tightly woven, cross-linked conduit that is flexible and compliant.

Group will receive any standard ePTFE graft (control) based on the surgeons' discretion. The graft will be placed either in the arm (brachial artery to axillary vein) or forearm (brachial artery to cephalic or suitably sized vein) depending on which location works best in your particular case.

Group will receive the BCA graft (experimental).The graft will be placed either in the arm (brachial artery to axillary vein) or forearm (brachial artery to cephalic or suitably sized vein) depending on which location works best in your particular case.

Primary patency is defined as the interval from graft placement to any intervention for stenosis with or without complete occlusion (thrombosis).

Assisted primary patency is defined as the interval from graft placement to the first episode of complete occlusion.

Functional patency represents the interval from the first time the graft is used for hemodialysis to any qualifying event (stenosis, thrombosis, graft failure)

Primary patency is defined as the interval from graft placement to any intervention for stenosis with or without complete occlusion (thrombosis).

Assisted primary patency is defined as the interval from graft placement to the first episode of complete occlusion.

Functional patency represents the interval from the first time the graft is used for hemodialysis to any qualifying event (stenosis, thrombosis, graft failure)

The presence of erythema or purulent drainage at the surgical incision and need for intravenous antibiotics or surgical intervention.

The presence of erythema or purulent drainage at the surgical incision and need for intravenous antibiotics or surgical intervention.

The presence of erythema or purulent drainage at the surgical incision and need for intravenous antibiotics or surgical intervention.

The presence of erythema or purulent drainage at the surgical incision and need for intravenous antibiotics or surgical intervention.

Steal syndrome will be staged per standard as follows: Stage I: pale/blue and/or cold hand without pain; Stage II: Pain during exercise and/or hemodialysis; Stage III: Rest pain; Stage IV: Ulcers/necrosis/gangrene. Accordingly, surgical intervention will be carried out for patients with stage III or IV steal.

Steal syndrome will be staged per standard as follows: Stage I: pale/blue and/or cold hand without pain; Stage II: Pain during exercise and/or hemodialysis; Stage III: Rest pain; Stage IV: Ulcers/necrosis/gangrene. Accordingly, surgical intervention will be carried out for patients with stage III or IV steal.

Steal syndrome will be staged per standard as follows: Stage I: pale/blue and/or cold hand without pain; Stage II: Pain during exercise and/or hemodialysis; Stage III: Rest pain; Stage IV: Ulcers/necrosis/gangrene. Accordingly, surgical intervention will be carried out for patients with stage III or IV steal.

Steal syndrome will be staged per standard as follows: Stage I: pale/blue and/or cold hand without pain; Stage II: Pain during exercise and/or hemodialysis; Stage III: Rest pain; Stage IV: Ulcers/necrosis/gangrene. Accordingly, surgical intervention will be carried out for patients with stage III or IV steal.

At hemodialysis, the grafts will be accessed with 15 or 17 gauge needles inserted at any angle between 25-30 degrees (the same method used for a native arterio-venous fistula). If by physical examination the graft is thrombosed, then the patient will immediately be referred for endovascular thrombectomy and revision. If the graft is patent, but problematic, the patient will be referred for an urgent fistulogram and endovascular reintervention

At hemodialysis, the grafts will be accessed with 15 or 17 gauge needles inserted at any angle between 25-30 degrees (the same method used for a native arterio-venous fistula). If by physical examination the graft is thrombosed, then the patient will immediately be referred for endovascular thrombectomy and revision. If the graft is patent, but problematic, the patient will be referred for an urgent fistulogram and endovascular reintervention

At hemodialysis, the grafts will be accessed with 15 or 17 gauge needles inserted at any angle between 25-30 degrees (the same method used for a native arterio-venous fistula). If by physical examination the graft is thrombosed, then the patient will immediately be referred for endovascular thrombectomy and revision. If the graft is patent, but problematic, the patient will be referred for an urgent fistulogram and endovascular reintervention

At hemodialysis, the grafts will be accessed with 15 or 17 gauge needles inserted at any angle between 25-30 degrees (the same method used for a native arterio-venous fistula). If by physical examination the graft is thrombosed, then the patient will immediately be referred for endovascular thrombectomy and revision. If the graft is patent, but problematic, the patient will be referred for an urgent fistulogram and endovascular reintervention

Inclusion Criteria: Patients at least 18 years of age Have End Stage Renal Disease and are undergoing Arterio-Venous-Graft surgery Not Eligible to receive an Arterio-Venous-Fistula Provided written informed consent Agreed to return for all required clinical follow up for the study Exclusion Criteria: Eligible to receive an Arterio-Venous-Fistula Known allergic reaction or history of intolerance to any ePTFE or BCA components Local infection at AVG placement site at the time of surgery Patients with a bleeding disorder or who refuse blood transfusion Patients with an active malignancy Life expectancy less than 1 year Pregnant women or those planning on becoming pregnant for the duration of the study

Only key study personnel will be responsible for entering and tracking information. At the end of the study period, study coordinators and research fellows will have access to the final trial dataset and will analyse the data. The final results will be communicated to the PI and co-PI's, the sponsors and participants and will be later published in a peer-reviewed scientific journal.

Dakour Aridi H, Arhuidese I, Scudder M, Reifsnyder T, Malas MB. A prospective randomized study of bovine carotid artery biologic graft and expanded polytetrafluoroethylene for permanent hemodialysis access. J Vasc Surg. 2018 May;67(5):1606-1612.e4. doi: 10.1016/j.jvs.2017.12.058. Epub 2018 Mar 19.