Patient discomfort during carotid artery stenting: a comparison study between iodixanol versus iopamidol

Background The aim of this study was to compare the adverse effects of iodixanol and iopamidol in terms of patient's discomfort in subjects undergoing carotid artery stenting (CAS). Methods We retrospectively analyzed data of all successful CAS procedures performed in our department during a 15-year period study. All patients judged to be collaborative were included. From December 2000 to December 2005, we adopted iopamidol as contrast media (CM), thereafter iodixanol. Any transient unpleasant sensation of bitter taste or warmth perceived by the patient after intra-arterial injection of CM was recorded. Injection-associated discomfort was assessed by visual analog scale (VAS) score. Comparison between the 2 CMs with regard to the overall discomfort was carried out by using the Mann–Whitney test. Spearman correlation was performed to assess the correlation among discomfort, age, and CM used. A univariate analysis was performed for slightly bitter taste and warmth sensation to compare these clinical outcomes and CM used; subsequently, a logistic multivariate analysis regression was performed with the “backward elimination.” Results Data from 1,633 patients were evaluated. A total of 608 patients underwent CAS procedure using iopamidol, and 1,025 using iodixanol. The total amount of CM used during a single procedure was 85 ± 17 mL/patient (range 60–135). The median VAS value was statistically significantly lower in the iodixanol group than in the iopamidol group (P < 0.001). A significant Spearman correlation coefficient was found between age and discomfort for both CMs used (Spearman rho 0.18 for iodixanol, 0.17 for iopamidol). The univariate analysis showed that patients undergoing CAS with iopamidol had an odds ratio (OR) of 8.48 (P < 0.001) to perceive warmth sensation. When adjusted for age and gender, the multivariate analysis still showed an OR of 8.03. For slightly bitter taste sensation, the crude analysis showed an OR of 1.31 (P = 0.018); adjusting for age and gender, OR became 1.15 and the difference was not statistically significant (P = 0.257). Conclusions During CAS, less overall discomfort was reported in patients receiving iodixanol than iopamidol; in terms of warmth sensation, patients undergoing procedure using iopamidol as CM have a higher risk to perceive this clinical symptom than iodixanol. Slightly bitter taste seems to have a statistically significant relation with age and gender, and not with CM used.