Zero-Contrast EVAR Can Be Reached Using Automated Carbon Dioxide Digital Angiography, Endoaortic Balloon Occlusion,...

To introduce a new method to enhance the visualization of renal arteries and the accuracy of graft deployment during CO₂-assisted endovascular (EV) aneurysm repair (EVAR).

A retrospective observational study of consecutive EVAR cases assisted with CO₂ angiography (CO₂Angio) was conducted. This nonrandomized design reflects real-life progressive attempts to enhance the reliability of CO₂ and intravascular ultrasound (IVUS), minimizing the use of iodinated contrast (IC) and radiation, respectively. Cases were divided into 3 groups according to consecutive periods: CO₂Angio (n = 7), CO₂Angio and balloon occlusion of the infrarenal aorta (CO₂Angio + EVclamp, n = 11), and CO₂Angio + EVclamp + IVUS (n = 18). IC was permitted in case of insufficient visualization with CO₂Angio during any phase of the procedure. Demographic, clinical, and procedure variables (volume of IC and CO₂, radiation, fluoroscopy time, leaks) were collected from electronic clinic histories and statistically analyzed.

A significant decrease was found in the third group, after introducing both techniques, for total radiation (air kerma; 3,039 ± 2,792.3 vs 3,434.7 ± 1,289.2 vs 2,284.6 ± 841.5 mGy, P = 0.041), radiation per area, dose area product (47 ± 34.7 vs 54.5 ± 15.3 vs 41.3 ± 12.8 mGy×m², P = 0.03), and IC volume (104.3 ± 102.4 vs 89.2 ± 53.9 vs 15.4 ± 27.4 mL, P < 0.001), arriving at the goal of "zero contrast" in the last 12 patients. No significant differences were detected in fluoroscopy time, total operative time, total CO₂ volume, or change in renal function.

The introduction of endoluminal occlusion with a balloon and the use of IVUS in CO₂-assisted EVAR enabled us to achieve the objective of zero contrast and a progressive decrease in radiation dose.