The Need for Universal Access to More Flexible Endovascular Stent Graft Constructs

Abstract

Abdominal aortic aneurysm (AAA) is the 13th leading cause of death in the United States, responsible for over 15,000 deaths annually. With improved screening methods and the advent of endovascular surgery, mortality from AAA has significantly decreased over the past twenty years [1]. Today it is estimated that >70% of aneurysms are amenable to endovascular repair [2]. While endovascular aortic aneurysm repair (EVAR) is confined to the treatment of infra-renal AAA with a ≥10 mm neck, complex endovascular stent grafts have been developed to treat AAA with <4 mm infra-renal neck (juxta-renal), involving the renal or visceral vessel orifices (para-renal or para-visceral), or extending to the diaphragm (Type IV thoraco-abdominal aneurysm) or thoracic aorta. It is estimated that 16% of infrarenal aortic aneurysms are juxta-renal, and a smaller percentage involve the more proximal abdominal aorta [3]. Fenestrated and branched endografts have been developed to treat proximal AAAs not amenable to standard EVAR. However, the extent of what can be treated is limited in the United States by the specific instructions for use (IFU) of each device and what has gone through the rigorous process of FDA approval. Instructions for use outline the recommended anatomic constraints for each device to maximize positive outcomes by guiding patient and device selection. Physicians can treat outside of the IFU but bear significant liability. While certain centers in the US conducting investigational research have access to order endografts outside of their IFU, practitioners in other countries are able to customize devices without these constraints. Patients who could otherwise undergo endovascular repair may be subject to high-risk open surgery, off-label use of devices to perform chimney/snorkel procedures, off-label use of existing FDA approved fenestrated devices, or medical management (at increased risk for aneurysm related death) due to these current restrictions.