Comparative outcomes of arterial bypass using the human acellular vessel and great saphenous vein in patients with chronic limb ischemia

Objective: The Human Acellular Vessel (HAV) is a novel, off-the-shelf biologic conduit being evaluated for arterial reconstructions. Regulatory studies in peripheral arterial disease (PAD) to date have consisted of single-arm cohorts with no comparator groups to contrast performance against established standards. This study aimed to compare outcomes of the HAV with autologous great saphenous vein (GSV) in patients with advanced PAD undergoing infrageniculate bypass.

Methods: Patients with advanced PAD and no autologous conduit who underwent bypass with the 6-mm diameter HAV (Group 1; n = 34) (March 2021-February 2024) were compared with a multicenter historical cohort who had bypass with single-segment GSV (group 2; n = 88) (January 2017-December 2022). The HAV was used under an Investigational New Drug protocol issued by the Food and Drug Administration (FDA) under the agency's Expanded Access Program.

Results: Demographics were comparable between groups (mean age 69 ± 10 years; 71% male). Group 1 had higher rates of tobacco use (37 pack-years vs 28 pack-years; P = .059), coronary artery disease (71% vs 43%; P = .007), and prior coronary artery bypass grafting (38% vs 14%; P = .003). Group 1 had more patients classified as wound, ischemia, and foot infection clinical stage 4 (56% vs 33%; P = .018) and with previous index leg revascularizations (97% vs 53%; P < .001). Both groups had a similar number of patients with chronic limb-threatening ischemia (Rutherford class 4-6) (88% vs 86%; P = .693) and Global Anatomic Staging System stage III (91% vs 96%; P = .346). Group 1 required a composite conduit (two HAV sewn together) in 85% of bypasses. The tibial vessels were the target in 79% of group 1 and 100% of group 2 (P < .001). Group 1 had a lower mean operative time (364 minutes vs 464 minutes; P < .001). At a median of 12 months, major amputation-free survival (73% vs 81%; P = .55) and overall survival (84% vs 88%; P = .20) were comparable. Group 1 had lower rates of primary patency (36% vs 50%; P = .044), primary-assisted patency (45% vs 72%; P = .002), and secondary patency (64% vs 72%; P = .003) compared with group 2.

Conclusions: Implanted under Food and Drug Administration Expanded Access provisions, the HAV was more likely to be used in redo operations and cases with more advanced limb ischemia than GSV. Despite modest primary patency, the HAV demonstrated resilience in a complex cohort with no autologous conduit options, achieving good secondary patency and providing major amputation-free survival comparable with GSV at 12 months.