Carbon Dioxide Angiography as a Sole Contrast Modality in Endovascular Procedures

Iodinated contrast medium (ICM) carries risks of allergic reaction and post-contrast acute kidney injury (PC-AKI). Carbon dioxide (CO₂) angiography offers a potential alternative for patients with renal insufficiency or ICM allergy. Although extensive international studies have demonstrated the efficacy of CO₂ angiography, data on local populations remain limited. To provide region-specific data, we evaluated the accuracy and safety of CO₂ as the sole contrast modality in regional endovascular procedures.

Clinical data of 28 patients who underwent various endovascular procedures using CO₂ angiography alone from April 2021 to December 2025 were retrospectively collected and analyzed. The primary endpoint was technical success. Secondary endpoints included postoperative renal function impairment and the incidence of complications.

The technical success rate for procedures performed with CO₂ angiography alone was 92.86% (26/28 cases). Serum creatinine (sCr) levels at 24 hours and 1 month postoperatively [112.85 μmol/L (IQR, 63.52-357.57) and 104.70 μmol/L (IQR, 65.35-356.62), respectively] showed no statistically significant difference compared to preoperative levels [105.55 μmol/L (IQR, 64.15-349.23)] (P > .05). In the 13 patients with pre-existing renal insufficiency, mean sCr at 24 hours (358.70 ± 94.53 μmol/L) and 1 month (353.68 ± 90.10 μmol/L) also did not differ significantly from the preoperative mean (355.37 ± 91.64 μmol/L) (P > .05). Two patients undergoing renal artery stenting required adjunctive ICM (10 mL and 15 mL, respectively) due to suboptimal image quality. No CO₂-related complications occurred in any patient during or after the operation.

Within the constraints of a small retrospective design, CO₂ angiography appears to be a feasible and acceptably safe imaging alternative for specific endovascular procedures, particularly in patients with contraindications to ICM. These preliminary findings require confirmation through larger, prospective, multicenter investigations before broader clinical adoption can be recommended.