Ensuring Non-Leakage Performance in Thoracic Aortic Repair in Preclinical Performance of a Minimally Invasive Thoracic Stent Graft: Results from a Porcine Model Study

Abstract

The MeriGraft™ Thoracic Endovascular Stent Graft System was evaluated for its performance and safety in a controlled, one-day acute study using two large female porcine. Designed for minimally invasive repair of thoracic aortic aneurysms, the device was delivered via a 22-25F catheter introduced through the right femoral artery in the animal model. To evaluate the performance and safety of the MeriGraft™ Thoracic Endovascular Stent Graft System, an acute porcine model study was conducted. This one-day study aimed to assess stent leakage and overall feasibility of the device. The focus was on identifying any potential issues with fabric leakage, which could lead to Type 2 endoleaks. The study concluded that to prevent such leaks, the stent graft must be manufactured with high-quality fabric, as demonstrated by the animal study data. The Present study has an object to study that MeriGraft™ Thoracic Endovascular Stent Graft System is functionally suitable for its applications of assuring no leakage. While selecting the large animals we found the femoral artery is not suitable for its delivery system as in MeriGraft™ Thoracic Endovascular Stent Graft System it is fairly wider than available diameter of femoral artery. Yet the objective of suitability of MeriGraft™ Thoracic Endovascular Stent Graft System can be established if no blood leakage is found as per expectations from this under fluoroscopic guidance. Angiography was used to determine the appropriate stent graft sizes: 24x167 mm for P1 and 28x167 mm for P2. Both stents were successfully deployed in the descending aorta, expanding self-expansionally without procedural complications or mortality. Throughout the procedure, clinical monitoring showed no abnormal signs, and pre- and post-deployment blood tests revealed no significant changes, indicating stable hematological and biochemical profiles. The device's handling, visualization, hemostasis, and deployment were all found to be effective. Angiographic assessment confirmed proper endovascular flow and accurate stent graft positioning with no migration. X-ray imaging showed no structural or material disintegration. Histopathological analysis of the explanted aortas revealed no signs of inflammation, vascular injury, smooth muscle cell loss, or endothelial damage. Additionally, histomorphometric analysis demonstrated a beneficial increase in the internal luminal diameter with minimal changes in neointimal tissue. The device successfully sealed the aneurysm site, and no safety concerns were observed under acute testing conditions. These results affirm that the MeriGraft™ Thoracic Endovascular Stent Graft System system is effective and safe, offering a promising minimally invasive approach to treating thoracic aortic aneurysms.