Durability and Infection Resistance of Cryopreserved Femoral Vein Allografts in Suprainguinal Position. A Single Center Study

Abstract

Introduction - There is no consensus about the best treatment method of aortic graft infections (AGI) and primary arterial infections in aorto-iliac area. Cryopreserved arterial allografts have proved to be infection-resistant, but long-term durability is altered by late graft thrombosis and degeneration 1,2. However, cryopreserved big caliber venous allografts’ performance in aorto-iliac position is unknown. The aim of current study was to evaluate cryopreserved femoral vein allografts’ (CVA) safety, infection resistance and durability in suprainguinal setting in infectious conditions and compare their performance with cryopreserved arterial allografts (CAA) from the same homograftbank. Methods - Patients treated from February 2012 to March 2018 with cryopreserved allografts’ reconstruction due to infection encompassing suprainguinal area in a tertiary level hospital were retrospectively reviewed. Preoperative characteristics, indication for operation, operative details, early postoperative morbidity and mortality, late mortality, re-infections and graft re-interventions during the follow-up were recorded. Univariable analysis was done using crosstabs method, survival calculated with Kaplan-Meier method. Results - 31 patients underwent cryopreserved venous (femoral vein, n=21; cava vein, n=2) or arterial (superficial femoral artery, n=6; aorta, n=1; iliac artery, n=1) allograft reconstruction due to infection in aorto-iliac area. Indications for treatment were AGI in 14 (45%), mycotic aneurysm in 5 (16%), extra-anatomical prosthetic infection in 5 (16%), secondary arterial infection with rupture in 2 (6%), anastomotic pseudoaneurysm in 2 (6%) and aortic thrombosis with intestinal spillage in 1 (3%) case. 30-day and overall treatment-related mortality was 4 (13%). During the median follow-up of 15 month, two CAAs were treated due to thrombosis, two CVAs due to anastosmotic dilatation and one CVA due to re-infection and subsequent rupture making re-intervention incidence 16% (n=5). None of the grafts were lost and there were no amputations. At the end of follow-up 22 (71%) patients were alive. Kaplan-Meier estimation of survival was 87% (95% confidence interval, 81% to 93%) at 1 year and 63% (52% to 74%) at 2 years. Univariable analysis revealed no risk factors significantly associated with 30-day mortality, however cerebrovascular disease (p=0,028) was associated with treatment-related mortality and renal insufficiency (p=0,004) with overall total mortality. Due to small number of patients statistical analysis comparing CAA and CVA were unreliable, but two acute arterial occlusions call for caution and further research. Conclusion: Cryopreserved venous allografts appear safe, infection-resistant and durable reconstruction material in aorto-iliac axis based on single center experience and mid-term analysis. Further research is needed to compare their performance to cryopreserved arterial allografts and other biological reconstruction material.