CO₂ angiography offers clinical advantages over iodinated contrast in endovascular aneurysm repair: a systematic review and meta-analysis

Abstract

Objective: This study evaluates the safety, efficacy, and clinical outcomes of carbon dioxide (CO₂) versus iodinated contrast media (ICM) in endovascular aneurysm repair (EVAR), an area where comprehensive combined imaging and clinical assessments have yet to be explored. Methods: A comprehensive literature search was conducted in PubMed, Embase, and Scopus from their inception to May 2025, specifically targeting studies published since 2012 that compared contrast media in EVAR. Outcome measures—including operative time, fluoroscopy time, procedural success (defined as postoperative restoration of blood flow), renal function, incidence of acute kidney injury (AKI), and type II endoleak—were analyzed using a generalized linear mixed model. Results: Compared with ICM, CO₂ angiography showed no significant differences in procedural success or operative time (both P > 0.05), while fluoroscopy duration was slightly longer (WMD = 2.75, P < 0.001). CO₂ angiography was associated with markedly reduced ICM exposure (WMD = − 57.24, P < 0.05) and showed potential renal benefits, including higher eGFR (WMD = 0.42, P < 0.001) and lower serum creatinine at 1 month (WMD = − 0.09, P = 0.04). The incidence of postoperative acute kidney injury was also lower in the CO₂ group (1.3% vs. 2.8%; OR = 0.43, P = 0.05). Moreover, CO₂ angiography showed a reduced incidence of type II endoleaks (OR = 0.57, P = 0.04), although further confirmation in larger prospective studies is warranted. Conclusion: Based mainly on observational data with limited prospective studies, CO₂ angiography in EVAR shows comparable intra-procedural visualization and technical success to ICM. Some studies suggest it may reduce perioperative AKI risk or provide short-term renal protection. However, current evidence is insufficient to establish its equivalence across all patient populations. Therefore, its use should be individualized based on factors like renal function and anatomy or considered alongside low-dose ICM.