A prospective, randomized trial to determine the early and late reactions after the use of iopamidol 340 (Niopam) and iobitridol 350 (Xenetix) in cardiac catheterization

BACKGROUND: Intravascular contrast agents presently used in modern digital catheter laboratories during cardiac catheterization are superior to older agents as regards patient tolerance. There are, however, significant differences between these agents. PURPOSE: The aim of this study was to determine the incidence of early (< 24 hours) and late (> 24 hours to 7 days) reactions to 2 contrast agents currently used during cardiac catheterization: iopamidol 340 (Niopam) and iobitridol 350 (Xenetix). METHODS: This was a prospective, randomized, double-blinded trial. Two thousand and nineteen patients undergoing cardiac catheterization received one of the following contrast agents: iopamidol 340 (Niopam) and iobitridol 350 (Xenetix). Reactions that were possibly related to the contrast agents were recorded during hospital admission (early reaction) and after discharge (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 2 groups, (p = 0.1). Early non-heat reactions occurred in 3.2% of patients receiving iopamidol 340 (Niopam) and 3.6% of those receiving iobitridol 350 (Xenetix), (p = 0.65). Electrocardiographic changes were recorded in 0.7% of patients who received iopamidol 340 (Niopam), and 2.6% of those who received iobitridol 350 (Xenetix), (p = < 0.01). Seven patients (0.8%) receiving iobitridol 350 suffered ventricular fibrillation requiring DC cardioversion compared with none in the iopamidol 340 group (p = < 0.01). Late reactions (post discharge symptoms) occurred in 13.9% of those receiving iopamidol 340 (Niopam) and 18.5% of those receiving iobitridol 350 (Xenetix) (p = 0.02). CONCLUSIONS: Iobitridol 350 (Xenetix) was associated with more ECG changes and, importantly, ventricular fibrillation, than iopamidol (Niopam). There were no features to suggest other benefits from iobitridol 350. These results suggest that iopamidol 340 is a preferable contrast agent in cardiac catheterization.