The Research Of Designation And Improvement Of A New Split-type Aortic Stent-graft System

Abstract:Objectives:To design and manufacture a new split-type stent-graft system for ascending aortic and aortic arch lesions, using non-patient-specific, total endoluminal technique.Methods:We raise the concept of a new split-type stent-graft system with the aim of treating ascending aorta and aortic arch lesions. This system consists of a stent-graft main body which is used in the aorta with a sunken area in the middle part and several branch stent-grafts with proximal "plate"-like structure. We made two types of this stent-graft system with different diameter and length. We tested the applicability and safety of this stent-graft system by ex-vivo and canine in-vitro tests and improved the designation and making process according to the results. The applicability and safety was then tested again by ex-vivo and canine in-vitro tests.Results:Two different types of this split-type stent-graft system were designed and manufactured successfully. As to large-type stent-graft system, the process of ex vivo test was sound and safe, all stent-grafts were successfully deployed. Due to ethnic problems, in-vitro tests cannot be done at this moment. To middle-type stent graft system, in the ex vivo test, the main body was successfully deployed in the aorta. The delivery system of branch stent-graft cannot reach to branch arteries, so the test had to be suspended. And in the in-vitro test, all stent-grafts were deployed. The deployment of main-body stent-graft was successful but the configuration was poor. The stent-grafts migrated and deformed in the process of branch stent-graft delivery system extraction. The flaws were collected and corrected in the designation and making-process. The ex vivo and in-vitro tests were then performed to test the applicability and safety of this improved stent-graft system. Both tests were successfully performed. All stent-grafts were deployed with good configuration. The connection of stent-grafts was firm. DSA showed no endoleak.Conclusion:The designation and making-process of this new split-type aortic stent-graft system was successful. The applicability and safety of this stent-graft system was tested in ex vivo and in-vitro tests.