Histologic analysis of stent graft oversizing in the thoracic aorta

Blunt aortic injury is a catastrophic event that most commonly affects the descending thoracic aorta, and it is the second most common cause of death in trauma patients. Thoracic endovascular aortic repair is increasingly being used to treat such conditions. The prostheses available at the time we conducted the present study were not specifically designed to treat thoracic aortic trauma. Furthermore, few stent grafts had been designed for use in normal or healthy aortic tissue or in young patients with acute angulation of the thoracic aorta. To our knowledge, no large study has evaluated the optimal target level of oversizing in thoracic aortas, especially for nonatherosclerotic aortas. We have conducted an experimental study in which we evaluated the biomechanical changes associated with four levels of stent graft oversizing on a nonatherosclerotic aortic wall. In the present report, we describe the histologic and immunohistochemical results of that study.