Biomechanical study of hepatic portal vein in humans and pigs and its value in liver transplantation.

Objective: Our aim was to explore the biomechanical properties of hepatic portal vein (HPV) in humans and pigs to provide evidence for liver xenotransplantation.
Materials and Methods: The pressure-diameter relationships of HPV from 6 deceased donors and 36 pigs were measured on a biomechanical experimental stand to calculate the elastic modulus and compliance. Each sample sliced into 5-mm frozen sections was stained with hematoxylin-eosin (H&E). Geometric morphological indices were measured with a computer image analysis system.
Results: The length, wall thickness, and diameters of HPV in pigs increased from 1 to 6 months (P < .05). There were no significant differences between 6-month-old pigs and adult humans (P > .05). The incremental elastic modulus of the pig HPV increased with age, whereas the compliance decreased. There was no difference in the elastic modulus of HPV between 5- to 6-month-old pigs and humans (P > .05). Also, there was no difference in HPV compliance between 6-month-old pigs and humans (P > .05).
Conclusions: Our results suggested that the biomechanical properties of HPV in 6-month-old pigs were similar to those of humans. From a biomechanical perspective, anastomosis of corresponding HPV from 6-month-old pigs to humans may be feasible in the process of pig-to-human liver xenotransplantation.