Alternative autologous and biologic conduits have worse outcomes than prosthetic grafts for infrainguinal bypass in patients with chronic limb-threatening ischemia

Abstract

Objective: Single segment great saphenous vein (GSV) is the preferred conduit in infrainguinal bypass. Alternative autologous conduits (AAC) and nonautologous biologic conduits (NABC) are thought to be a better alternative to traditional prosthetic conduits (PC) in the absence of GSV. In this study we analyzed the outcomes of these alternative conduits in lower extremity bypasses (LEB) in patients with chronic limb-threatening ischemia.

Methods: The Vascular Quality Initiative LEB database from 2003 to 2020 was queried for this study, to identify LEB in patients with chronic limb-threatening ischemia. Primary outcomes were graft patency, major adverse limb events (MALE), and MALE-free survival at 1 year. Standard statistical methods were used as appropriate.

Results: We identified 22,671 LEB procedures (12,810 GSV, 6002 PC, 1907 AAC, and 1952 NABC). Compared with the GSV group, the other conduit patients were significantly older, had more comorbidities, had an increased rate of prior lower extremity interventions, had a higher rate of infrageniculate bypass targets, and were less ambulatory at baseline. The PC, AAC, and NABC groups had significantly higher rates of postoperative morbidity compared with the GSV group. The PC group had a higher 30-day mortality compared with the GSV, AAC, and NABC groups (3% PC vs 2% GSV, 2% AAC, 2% NABC; P = .049). Both PC and NABC had higher 1-year mortality compared with GSV and AAC (13% PC and 13% NABC vs 10% GSV, 10% AAC; P = .02). In an adjusted Cox regression model (stratified by infrageniculate target and adjusted for age, comorbidities, and prior vascular interventions) PC was not significantly different from GSV, but AAC (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.19-1.67; P < .001) and NABC (HR, 1.9; 95% CI, 1.61-2.25; P < .001) were associated with an increased risk of loss of primary patency. A similar association with MALE was observed: both AAC (HR, 1.35; 95% CI, 1.15-1.58; P < .001) and NABC (HR, 1.8; 95% CI, 1.53-2.11; P < .001) were associated with an increased risk of MALE compared with GSV; PC was not significantly different from GSV.

Conclusions: In the absence of GSV, alternative conduits (autologous or nonautologous biologic) do not confer a benefit with regard to graft patency or MALE compared with PCs. Increased operating time or costs associated with the use of these conduits is not justified based on this study.

Keywords: Alternative conduit; Loss of patency; Lower extremity bypass; Major adverse limb events; Outcomes.

Fig 1.

(A) Unadjusted Kaplan-Meier (KM) estimates of primary patency at 1 year. (B) Unadjusted KM estimates of major adverse limb events (MALE) at 1 year. (C) Unadjusted KM estimates of MALE-free survival at 1 year. AAC, alternative autologous conduits; GSV, great saphenous vein; NABC, nonautologous biologic conduits.

Fig 2.

(A) Unadjusted Kaplan-Meier (KM) estimates of primary patency at 1 year. (B). Unadjusted KM estimates of amputation free survival at 1 year. AAC, alternative autologous conduits; GSV, great saphenous vein; NABC, non-autologous biologic conduits

Fig 3.

Adjusted Cox regression models of primary patency, major adverse limb events (MALE), and MALE-free survival at one year stratified by infrageniculate target. AAC, alternative autologous conduits; GSV, great saphenous vein; HR, hazard ratio; NABC, nonautologous biologic conduits; PC, prosthetic conduits.