Objectives Traditionally, acute mesenteric ischemia studies are performed by utilizing an open superior mesenteric artery (SMA) occlusion, which is an invasive technique with potentially devastating effects. A new endovascular technique for SMA occlusion using a catheter-balloon system was designed and compared to the open SMA occlusion to test its efficacy and animal safety. Methods All animals underwent open instrumentation of the superior mesenteric vein (SMV) for blood flow monitoring. The animals were grouped into an open SMA occlusion technique group and an endovascular SMA occlusion group. The open SMA occlusion technique group involved exposure of the SMA via left medial visceral rotation with vascular clamping. In the endovascular group, an endovascular balloon was placed in the SMA and inflated to produce occlusion. Results Complete cessation of flow to the SMV was observed in the endovascular group, compared to the residual SMV flow in the open occlusion group. Following a 30-min post-occlusion period, the MAP in the endovascular group increased, compared to a decline of MAP in the open occlusion group. Conclusions This study indicates the endovascular technique provides a more potent SMA occlusion, with insignificant consequences on the overall health of the animal, in contrast to the open vascular clamping.
Developing a Carotid Pseudoaneurysm Model in Swine
Background: Traumatic carotid artery pseudoaneurysms (PSAs) represent a vascular anomaly with potential for serious complications, including stroke. Traditional treatments involve endovascular stenting, which may not be ideally suited to otherwise healthy vessels that have the potential to remodel. Given the limitations of smaller animal models in replicating human vasculature and the need for improved treatment modalities, this study introduces a novel swine model for the creation and evaluation of carotid PSAs. Methods: The PSAs were created from bovine dura and anastomosed in an end-to-side fashion to bilateral carotid arteries. The PSAs were radiologically followed up post-operatively and were harvested at 3 and 10 days for histological analysis. Results: Pseudoaneurysms were successfully created in both animals without intra-operative or immediate post-operative complications. Radiological analysis showed well-perfused PSAs with intra-aneurysmal turbulence, hemodynamically mimicking human carotid artery PSAs. There was no evidence of thrombus or arterial stenosis. Histological examinations revealed thrombus maturation and tight anastomosis of the PSA sac with the native artery. Conclusions: This PSA swine model offers a replicable, cost-effective, and easily implemented tool with the potential to advance carotid PSA management and educational efforts in vascular surgery. Clinical Impact The model presented in this methodology paper allows for a standardized PSA animal model allowing for the standardization of a clinical entity which is frequently heterogenenous in morphology. This can allow for the development of new therapies or provide a ground truth for computer modelling for further in silico study.