A prospective randomised controlled trial to determine the early and late reactions after the use of iopamidol 340 (Niopam™) and iomeprol 350 (Iomeron ®) in cardiac catheterisation

Abstract

A new generation of intravascular contrast agents, the non-ionic monomers have safety profiles that are superior to those of older ionic compounds. There are, however, significant differences between these agents. Aim The aim of this study was to determine the incidence of early (<24 h) and late (>24 h to 7 days) reactions to two non-ionic contrast agents currently used during cardiac catheterisation: iopamidol 340 (Niopam™ Bracco UK Ltd.) and iomeprol 350 (Iomeron ® Bracco UK Ltd.). Methods This was a prospective, randomised, double blinded trial. One thousand nine hundred and eighty-five patients undergoing cardiac catheterisation received one of the following contrast agents on a weekly basis: iopamidol 340 (Niopam™) and iomeprol 350 (Iomeron ®). Reactions that were possibly related to the contrast agents were recorded on predefined data collection forms during the first 24 h of the procedure (early reaction) and after 24 h to 7 days (late reaction) by means of a questionnaire. Results The baseline characteristics were matched in both the groups. There was no significant difference in the incidence of heat sensation experienced between the two groups ( p = 0.1). Early non-heat reactions occurred in 2.7% of patients receiving iopamidol 340 (Niopam™) and 4% of those receiving iomeprol 350 (Iomeron ®) ( p = 0.1). Significant electrocardiographic changes were recorded in 1.7% of patients who received iopamidol 340 (Niopam™), and 1% of those who received iomeprol 350 (Iomeron ®) ( p = 0.2). Bradycardia occurred more frequently in the iopamidol 350 group (0.8%) compared to the iomeprol 350 group (0.1%) p = 0.02. Late reactions occurred in 16.2% of those receiving iopamidol 340 (Niopam™) and 21.7% of those receiving iomeprol 350 (Iomeron ®) ( p = 0.02). A total of 23 (3.7%) patients in the iopamidol group and 39 (6.2%) patients in the iomeprol group reported nausea, p = 0.01. Conclusions The incidence of early adverse reactions was similar with the two non-ionic contrast agents. Although bradycardia was slightly more frequent using iopamidol 340, nausea was reported more commonly 24 h after the procedure in patients receiving Iomeron 350 (Iomeron ®). We conclude that there were only minor clinical differences between these agents; both are safe and well tolerated.