A Hemodynamic, Metabolic and Histopathological Study of a Heterotopic Auxiliary Swine Liver Graft With Portal Vein Arterialization

Abstract

BackgroundAuxiliary heterotopic liver transplantation with portal vein arterialization (AHLT-PVA) is a model that has been hardly studied, despite its therapeutic potential. MethodsHemodynamic and biochemical characterisation was carried out during graft implantation, in a pig-to-pig model (n=15 AHLT-PVA). Furthermore a histopathological study was performed to establish microscopic alterations due to PVA. ResultsReperfusion of the arterialized graft produced an increase in heart rate (HR) vs baseline (P=.004) and vs inferior vena cava clamping phase (P=.004); and a decrease in systemic vascular resistance vs cava clamping phase (P=.021). At the end of implantation, cardiac output remained elevated (P=.001), likewise HR remained increased vs baseline phase (P=.002). Mean arterial pressure decreased with cava clamping, but was not affected by the reperfusion of the graft, nor the skin closure. The histopathological study at 3, 10, and 21 days post-PVA revealed that functional liver structure was maintained although it is common to find foci of perilobular necrosis on day 3 (P=.049), and perilobular connective tissue proliferation at day 10 (P=.007), vs native liver. ConclusionsThe described arterialized liver graft model minimises the number of vascular anastomoses vs previously described models. It is hemodynamically and metabolically well tolerated and the double arterial vascularisation of the graft does not cause significant changes in liver histology.