Safety and Effectiveness of Carbon Dioxide Contrast Medium in Infra-Inguinal Endovascular Interventions for Patients With Chronic Threatening Lower Limb Ischemia and Renal Impairment: A Multicentric Trial.

Purpose: To assess the safety and effectiveness of using carbon dioxide (CO₂) contrast in both supra- and infra-genicular endovascular interventions in patients with renal impairment.

Material and methods: This is a multicentric prospective observational study conducted over a period of 3 years from 2017 to 2020; the study included 114 patients presented with chronic threatening limb ischemia (CTLI) and renal impairment (lowest serum creatinine levels ≥1.3 mg/dL) for whom endovascular procedures were done using CO₂ as a contrast medium. Endovascular angiography was guided by CO₂ either exclusively (zero contrast) or with the aid of small amount of supplementary iodinated contrast media (ICM) injections. The qualitative assessment of the angiographic images in both supra- and infra-genicular fields were reported and scaled.

Results: The qualitative diagnostic images were excellent in 86.5% in the supra-genicular and 66.5% in infra-genicular images. There were no significant changes in mean serum creatinine levels from baseline to first and fifth days post procedural (mean 1.8 mg/dL vs mean 1.9 mg/dL and mean 1.7 mg/dL).

Conclusion: CO₂ is a non-nephrotoxic alternative to traditional ICM that could be safely used and well tolerated during endovascular interventions for peripheral arterial disease in patients with renal impairment. Primary safety and efficacy endpoints were achieved in 100% of cases. The use of automated injector system provides adequate delivery, optimizes the dose, and avoids air contamination. For infra-genicular segment opacification, we recommend super-selective injections and some changes in angiographic techniques from contrast preparation to image post-processing.

Clinical impact: Co₂ is a non-nephrotoxic alternative to traditional ICM that could be safely used and well tolerated during peripheral endovascular interventions in patients with renal impairment. The use of automated injector system would provide adequate delivery, optimizes the dose and avoids air contamination. For infra-genicular segment opacification, its recommended to use selective injection as close to the target artery as possible and some changes in angiographic techniques from contrast preparation to image post-processing.