Carbon Dioxide Guided Angiography in Endovascular Abdominal Aortic Aneurysm Repair

INTRODUCTION:

Endovascular aneurysm repair (EVAR) has lower short-term morbidity and mortality than open surgery. Intra-arterial contrast agents are an important component of successful EVAR as the tool of choice for preoperative evaluation of aortic aneurysm morphology as well as precise sizing and intraoperative visualization of the ostia of the renal and hypogastric arteries for graft replacement. Although iodinated contrast (IC) is overwhelmingly the most common contrast agent, the perioperative use of IC agents is not recommended in patients with renal dysfunction or allergies to IC.

Many strategies have been proposed with the aim of reducing IC developed, such as the use of intravascular ultrasound, high-quality 3-dimensional imaging techniques, and fusion of preoperative and intraoperative imaging. However, despite reports of various methods of renal protection, including the use of perioperative hydration, acetylcysteine, mannitol, dopamine, and fenoldopam, the effects of these methods are controversial.

Carbon dioxide (CO2)-guided angiography is an alternative contrast approach first described for diagnostic purposes by Hawkins. Although many studies have demonstrated the safety and effectiveness of CO2-EVAR and its noninferiority to Iodinated Contrast Angiography during EVAR.

Intravascular ultrasound (IVUS) has been used as an alternative to IACA(intra-arterial contrast agents). Originally, IVUS images had low accuracy, but recent improvements have resulted in very high-quality images of intra-aortic structures, which makes the use of IACA(intra-arterial contrast agents) almost unnecessary. An additional advantage of IVUS is that it facilitates the precise placement of stent grafts, because it is more accurate in locating hypogastric arteries and renal arteries which have parallax from the anteroposterior (A-P) view rather than from angiography. In this study, investigators will compare Carbon Dioxide Guided Angiography in relation to Iodinated Contrast Angiography during EVAR.