Animal model of a bovine pericardial patch for thoracoabdominal aortic aneurysms: step by step.

Abstract

Background: The treatment of thoracoabdominal aortic aneurysms (TAA) has advanced. Understanding the pathophysiology and surgical approaches to this disease is essential for best therapeutic performance.

Objectives: We aimed to improve previously described methods for creating thoracoabdominal aortic aneurysms in a porcine animal model, reducing surgical procedure time and specimen mortality.

Methods: A total of 18 swine underwent a surgical procedure to create a TAA. An autologous peritoneal patch was used to create the aneurysm in 2 animals, and a bovine pericardial patch was used in the other 16. The animals were followed up postoperatively, and the aneurysm sac was reexamined after 4 weeks. The animals that did not die in the post-operative period were euthanized according to institutional recommendations.

Results: All of the animals underwent laparotomy with retroperitoneal access. Two received an autologous peritoneal patch and 16 received a bovine pericardial patch. Three animals underwent single suprarenal clamping, while 15 underwent sequential clamping. There were no differences in operative time (p=0.207) or total clamping time (p=0.276) between groups. There was a higher mortality rate after 4 weeks in animals that received single clamping (100%) than sequential clamping (26.7%) (p=0.0017).

Conclusions: The experimental model of TAA using a bovine pericardial patch and a sequential clamping technique provided a stable and reliable platform that remains stable and patent for up to 4 weeks. This model can be extremely valuable for assessing new endovascular therapy options in living organisms.