Do Arterial Allografts Outperform Venous in Cryopreserved Bypass for Limb Salvage? A Systematic Review and Meta-Analysis of Infrainguinal Revascularization Outcomes.

BACKGROUND

Cryopreserved allografts remain a viable option for infrainguinal revascularization in limb salvage when autologous veins are unavailable or prosthetic material is undesirable. Uncertainty persists regarding comparative outcomes by allograft type (arterial vs venous) and clinical indication (infectious vs noninfectious settings). This systematic review and meta-analysis summarizes outcomes and key evidence gaps.

METHODS

A systematic search of studies reporting infrainguinal reconstructions with cryopreserved arterial or venous allografts was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (International Prospective Register of Systematic Reviews: CRD42024579097). Primary outcomes were 1-year primary patency, overall survival, and cumulative major amputation. Random-effects single-arm meta-analyses were performed with subgroup analyses by graft type and infection status. Risk of bias was assessed using Risk Of Bias In Nonrandomized Studies - of Interventions and certainty of evidence using Grading of Recommendation Assessment, Development, and Evaluation (GRADE). Secondary outcomes, including reintervention and graft-related complications, were narratively summarized.

RESULTS

Forty-two studies (2,237 patients; 2,170 limbs) were included: 25 were at serious risk of bias and 17 at moderate. Pooled 1-year primary patency was 51.1% (95% confidence interval [CI] 40.9-61.4%), overall survival 85.0% (95% CI 81.1-88.9%), and cumulative major amputation 20.2% (95% CI 15.7-24.7%). Arterial grafts had higher patency (67.6%; 95% CI 54.3-80.9%) than venous (39.6%; 95% CI 30.2-49.0%). Reconstructions for infection had superior patency (70.4%; 95% CI 55.2-85.6%) compared with noninfectious indications (44.2%; 95% CI 32.8-55.5%). GRADE certainty was very low.

CONCLUSION

Cryopreserved allografts enable limb salvage in complex chronic limb-threatening ischemia but show modest 1-year patency and substantial heterogeneity. Arterial conduit and use in infection were associated with superior early patency; robust comparative studies are required to optimize graft selection.