K. S. Lavingia1, C. Chipman1, S. S. Ahanchi1, J. M. Panneton1 1Eastern Virginia Medical School,Division Of Vascular Surgery,Norfolk, VA, USA
Introduction:
Our aim was to analyze the practical impact of CO2 enhanced angiography compared to conventional contrast angiography on interventional outcomes and renal function.
Methods:
A retrospective review of tibial interventions in patients with lower-limb ischemia was completed between 2008 and 2010. Patients were divided into a CO2 enhanced group and Iodixanol group. Outcomes were compared using Student’s t-test, Chi-squared analysis, and Kaplan-Meier Curves.
Results:
We reviewed 463 tibial interventions (87-% critical limb ischemia and 13-% claudication). All patients were subdivided into stage of chronic kidney disease (CKD): CKD1=86, CKD2=131, CKD3=110, CKD4=32, CKD5=103, 1 with incomplete laboratory data. The data was then divided into 56 interventions with CO2 enhanced imaging and 407 interventions with traditional Iodixanol contrast imaging. After exclusion of CKD5 patients, mean contrast volume for the CO2 enhanced group was 31mL ± 31 versus 104mL ± 65 for the Iodixanol group, p=<.001.
The mean age of the entire cohort was 71.6 ± 12 with 58% male. There was a statistically higher proportion of renal insufficiency (RI) in the CO2 enhanced group (48.2%) versus the Iodixanol group (9.2%), p=.02. Remaining demographics and risk factors were not statistically different between the 2 groups.
CKD5 patients were also removed for renal function analysis. The CO2 enhanced group versus the Iodixanol group had a higher mean preoperative creatinine (pre-Cr) 1.7 versus 1.1, p<.001 and a higher mean postoperative creatinine (post-Cr) 1.7 versus 1.2, p=.04. However, when comparing the change in Cr (ΔCr) as calculated by the post-Cr minus the pre-Cr for each patient, the mean ΔCr was not significantly different: with the entire cohort having a mean decrease in creatinine of .02.
Average follow up for the entire cohort was 18 months ± 15. Kaplan-Meier curves at 12 and 36 months showed no significant difference between the Iodixanol group versus CO2 enhanced group for primary patency (66%, 55% versus 75%, 69%; p=.212), primary assisted patency (85%, 76% versus 92%, 88%; p=.277), secondary patency (95%, 93% versus 97%, 97%; p=.501), limb salvage (85%, 78% versus 97%, 85%; p=.094), or reintervention rate (28% versus 21%, p=.34).
Conclusion:
Our results dispute the common perception that CO2 enhanced imaging protects renal function at the expense of image quality and ultimately primary outcomes in the tibial territory. CO2 enhanced angiography reduced the total contrast load and renal insult, without compromising outcomes, supporting the broader application of CO2 enhanced imaging during endovascular tibial interventions.