Cryopreserved vascular allografts for venous lengthening after robot-assisted living donor nephrectomy: a single...

Living-donor kidney transplantation (LDKT) is the gold standard for end-stage renal disease. Traditionally, the left kidney is preferred for its longer vein. However, the "donor safety first" principle, combined with the transition to laparoscopic and robotic donor nephrectomy, has increased the frequency of using right-sided grafts or encountering "iatrogenically" shortened veins due to mechanical stapling. In this study, we report our preliminary experience evaluating the efficacy of cryopreserved vascular grafts for renal vein lengthening in LDKT to overcome anatomical vascular length limitations.

All LDKT in this series were performed using a robotic-assisted laparoscopic approach. All procedures were carried out by a dedicated and experienced surgical team thanks to a cross-institutional partnership involving two regional University Hospitals. When necessary, cryopreserved venous allografts were employed to ensure adequate renal vein length. All transplants were carried out using a standard retroperitoneal approach in the iliac fossa.

From June 2024 to October 2025, nine living-donor kidney transplants were performed. The donor cohort included 7 females and 2 males with a median age of 58 years (IQR 51-69), while the recipient cohort included 4 females and 5 males with a median age of 39 years (IQR 23-55). Cryopreserved venous allografts were used in 5/9 LDKT (55.5%), following right kidney procurement. Cold ischemia time was higher in grafts requiring vascular extension than in those without elongation (median 139 min [IQR 130-141] vs. 115 min [IQR 107-121], respectively; p < 0.05). Rewarming time was also longer in the vessel extension group (median 38 min [IQR 37-40] vs. 33.5 min [IQR 31-35], respectively; p = 0.6). No intraoperative or high-grade postoperative complications were observed. At a median follow-up of 10 months (IQR 8-17), there were no deaths or graft losses. The median serum creatinine level at last follow-up was 1.6 mg/dL (IQR 1.2-1.7).

Renal vein lengthening with cryopreserved vascular grafts is a valuable tool in modern transplantation, addressing short veins-common in right-sided grafts and after laparoscopic or robotic stapling-and complex recipient venous anatomy. By enabling safer anastomoses, this technique supports excellent graft function while preserving donor safety.