Five prospective randomised controlled studies (RCTs), 2 prospective case series, 1 prospective cohort study and 15 retrospective case series were included in the review (3,263 patients; 3,837 allografts). The number of grafts performed ranged from 40 to 907. Follow-up ranged from 1 month to more than 5 years.
Cryopreserved allografts (5 studies): the weighted mean cumulative primary patency at 1 year' follow-up was 41%; 49% for arterial allografts (1 study) and ranging from 13 to 79% for venous allografts (4 studies). The weighted mean cumulative primary patency at 2 to 3 years' follow-up was reported as 31% (range: 18 to 79). It was reported that immunosuppression did not affect the patency of cryopreserved allografts, but no data were provided.
Cold-stored venous allografts (3 studies): the weighted mean cumulative primary patency was 71% at 1 year' follow-up (range: 63 to 80), and 51% at 2 to 3 years' follow-up (range: 38 to 62).
Glutaraldehyde-preserved venous allografts (15 studies): the weighted mean cumulative primary patency was 70% at 1 year' follow-up (range: 40 to 91) and 56% at 2 to 3-year follow-up (range: 33 to 86).
There was significant heterogeneity between prospective RCTs and meta-analysis could not be undertaken. A significant positive correlation was reported between the percentage of patients with Fontaine stage two disease and the 2-year cumulative primary graft patency (Pearson correlation coefficient 0.58; p=0.01).
Thirty-day mortality was reported in 14 studies, with an overall mortality rate of 2.9%. The incidence of major complications (17 studies) ranged from 0 to 15% and major limb loss (17 studies) ranged from 0 to 69%. Graft disintegration (17 studies) occurred in 0 to 15% of grafts. Cumulative secondary patency rates were reported in the review.