Endovascular Aneurysm Repair (EVAR) Gate Study

Endografts currently FDA-approved for abdominal aortic aneurysm (AAA) repair are modular systems,comprised of a main body (Aortic Trunk) and two legs (Ipsilateral Leg Endoprosthesis and a contralateral leg endoprosthesis). In placement of the endograft the main body and ipsilateral limb are deployed from a retrograde common femoral artery approach. From the contralateral femoral artery, cannulation of the contralateral gate is required to deploy the contralateral iliac limb.Cannulation of the contralateral limb gate is the portion of the operation that requires the most "wire skills." Depending on the patients' body type, angulations of the aorta and the size and volume of the AAA, this portion of the procedure can be technically difficult. This portion may become lengthy and discouraging if the surgeon fails to cannulate the gate using a particular approach. Cannulation of the contralateral limb gate from a retrograde femoral artery approach is commonly achieved by first using a maneuverable guidewire and steerable catheter. Antegrade or crossover cannulation involves passing a guidewire from the ipsilateral limb to the contralateral limb gate of the endograft, which can be accomplished with a curved catheter. The wire may be retrieved on the contralateral limb using a snare device. The problem and why it is important -- difficulty in accessing the contralateral gate leads to increase procedural time and excess exposure to radiation. The standard of care is retrograde cannulation with the use of crossover snare techniques as a secondary adjunct if retrograde cannulation fails. In this study we will compare retrograde cannulation to primary snaring.