Intraoperative Assessment of Pulsatile Aneurysm Wall Motion During Endovascular Aneurysm Repair

Endovascular abdominal aortic aneurysm repair (EVAR) aims to reduce the risk of aneurysm (AAA) rupture by reducing the blood pressure transmitted to the wall of the aneurysm. Unfortunately, this procedure is not always successful, and patients need to return to the operating room for further procedures because the aneurysm wall remains pressurized and the aneurysm continues to grow. Currently, there is no standard non-invasive way of measuring aneurysm pressure. The purpose of this study is to infer the reduction of pressure transmitted to the aneurysm wall by using intraoperative ultrasound ('M-Mode') to assess the pulsatility of the aneurysm wall. The hypothesis is that intraoperative reduction in aneurysm wall pulsatility after EVAR will correlate with improved aneurysm sac size reduction. This is clinically relevant because physiologic intraoperative feedback of aneurysm pressure may potentially influence surgical decision making in the future, reducing unnecessary re-interventions. This will also improve our understanding of the intraoperative physiologic response to EVAR.

Our primary research question is in patients receiving elective endovascular repair of abdominal aortic aneurysms (EVAR), does the change in intraoperative ultrasound estimated aneurysm wall pressure during EVAR correlate with aneurysm sac size reduction 1 year after surgery? Secondary objectives are to assess correlation between intraoperative ultrasound estimated aneurysm wall pressure and endovascular leaks and aneurysm-related re-interventions.

A prospective, observational, assessor-blinded and surgeon-blinded study will be conducted at the TOH Civic Campus in Ottawa, ON in order to satisfy the objectives of the study.