Outcomes of Infrapopliteal Bypass for Chronic Limb-Threatening Ischemia are Worse in Renal Transplant Patients than in Hemodialysis-Dependent Patients

Background: Comparisons of distal bypass outcomes between hemodialysis-dependent (HD) and renal transplant (RT) patients have been reported, but the influences of immunosuppressive therapy on the outcomes remain unclear because of the limited number of RT patients who un-derwent distal bypass or cohort heterogenicity. We compared outcomes of distal bypass for chronic limb-threatening ischemia (CLTI) with homogenous ischemic limb pathology. Methods: Between January 2014 and December 2019, we performed 334 infrapopliteal bypass procedures using vein grafts for 275 consecutive CLTI patients with tissue loss. Among them, there were 130 HD patients (47.3%) (163 limbs) and 11 RT patients (4%) (15 limbs), and 30 -day mortality, 5-year primary and secondary patency (PP and SP), limb salvage (LS), amputation-free survival rates, and wound healing (WH) status were compared between the HD and RT patient groups.Results: Nine HD patients died within 30 days after surgery (7%), whereas no deaths were observed among the RT patients. Five-year PP and SP rates in the RT group 39% and 41%, which were significantly worse compared to 64% and 82% in the HD group (P < 0.01). Unsuc-cessful rate of revision surgery including hemodynamically failed grafts after revision reached over 80% in the RT group, which was technically unfeasible pathology for graft salvage (vs. 3% in the HD group), and WH, and LS rates were significantly worse in the RT group.Conclusions: In comparison with HD patients, RT patients showed a lower LS rate for CLTI. The lower LS rate was associated with a lower SP rate, which was caused by disease progres-sion of distal arteries in the foot.