Carbon Dioxide Digital Subtraction Angiography Use in Endovascular Aneurysm Grafting

Alexander B. Chao, MD, Kevin Major, MD, Douglas H. Hood, MD and Fred A. Weaver, MD
University of Southern California, Vascular Surgery, Los Angeles, CA

Objective: Endovascular repair of abdominal aortic aneurysms (EVAR) is commonly performed using iodinated contrast agents. However, in patients with significant renal insufficiency or allergies to iodinated contrast, alternate agents may be preferable. This report summarizes our experience using carbon dioxide digital subtraction angiography (CO₂-DSA) to guide endograft placement.
Methods: An IRB-approved, retrospective review was performed of patients who underwent EVAR utilizing CO₂-DSA. Data collected included age, gender, and comorbidities including diabetes, hypertension, coronary disease, and smoking history. Intraoperative parameters including fluoroscopy time, total radiation dose, operative time, and presence and type of endoleak were also recorded. Data collected from the CO₂-DSA patients were compared to a concurrent series of patients who underwent EVAR utilizing iodinated contrast agents (ICA) only.
Results:
During the study period, 16 patients underwent EVAR utilizing CO₂-DSA, with supplemental use of iodinated contrast as needed in 12 patients. EVAR was performed in a concurrent set of 84 patients utilizing ICA only. Patient demographics and comorbidities were similar in both groups. Those patients who underwent CO₂-DSA had more radiation exposure as noted by longer fluoroscopy time and higher total radiation dose, as well as a longer operative time (Table 1). The preprocedure creatinine for the CO₂-DSA group was significantly higher than those receiving ICA only; there was no significant change in postprocedure creatinine for either group. Endoleaks were demonstrated in 6/16 patients (38%) in the CO₂-DSA group, compared to 34/84 (40%) patients in the ICA group (p=1.0). There were no adverse reactions attributed to CO₂ use.

Conclusions:
CO₂-DSA appears to be safe and efficacious for abdominal EVAR, with intraoperative endoleak detection comparable to ICA. Patients in whom CO₂-DSA was used required longer fluoroscopy times (the cause of which is unclear), with a trend towards higher total radiation delivered. We believe that in patients with contraindications to the use of iodinated contrast, CO₂-DSA is justified. We have initiated a prospective study directly comparing abdominal EVAR using CO₂-DSA to that using ICA.