Background
The aim of the study was to determine the prognostic significance of measurement of graft flow on the patency of distal bypass.
Methods
A retrospective analysis was performed for 208 distal bypasses (208 limbs, 170 patients) with a single segment great saphenous vein conducted in a nonreversed manner from January 2009 to December 2019 in Japan. Patient backgrounds, operative details (including intraoperative mean graft flow), hospital outcomes, and long-term outcomes were evaluated. The primary endpoints were the primary, assisted primary, and secondary patency of the distal bypass graft and the secondary endpoints were limb salvage and wound healing.
Results
The median intraoperative graft flow was 18 [10-30] mL/min. The follow-up rate was 98% in a mean follow-up period of 31 ± 26 months. Primary, assisted primary, and secondary patency in the cohort were 51%, 72%, and 73% at 1 year, and 39%, 59%, and 61% at 3 years, respectively. In multivariate analysis, the independent risk factors for primary patency were low graft flow (P = 0.0022) and female sex (P = 0.0016), and those for secondary patency were also low graft flow (P = 0.0025) and female sex (P < .001). The cut-offs for graft flow predicting primary and secondary patency were both 16 mL/min. The limb salvage rate was 94% at 1 year and 89% at 3 years; and the wound healing rates were 55%, 71% and 84% at 3, 6, and 12 months, respectively. Limb salvage and wound healing were not significantly associated with intraoperative graft flow.
Conclusions
Intraoperative graft flow was an independent predictor for graft patency in distal bypass, but had no influence on limb salvage and wound healing. The cut-off value for the mean graft flow predicting primary and secondary patency was 16 mL/min.
