Goal: To investigate the incidence of early (< 24 hours) and late (> 24 hours to 7 days) reactions to 3 contrast agents commonly used in cardiac catheterization.
Methods and results: A total of 2,108 patients undergoing cardiac catheterization in a Regional Cardiothoracic Unit were randomly assigned to receive 1 of 3 commonly used contrast agents in a prospective, double-blind study. The contrast agents were iopamidol 340 (Niopam ), a nonionic monomer; iomeprol 350 (Iomeron ), a nonionic dimer; and iodixanol 320 (Visipaque ), a nonionic dimer. The main outcome measures were the incidence of early (< 24 hours) reactions following catheterization and the incidence of late (24 hours to 7 days) reactions. Early reactions, excluding patients with heat on left ventriculography as the sole symptom, were relatively common (7.4%), but there was no significant difference between the 3 agents (p = 0.35). Late skin reactions, excluding reactions solely at the site of the arterial puncture and continuations of early urticarial reactions, were also relatively common (5.4%), but the incidence differed between the 3 agents. Such reactions occurred in 2.7% of those receiving iopamidol 340 (Niopam ), 3.5% of those receiving iomeprol 350 (Iomeron ) and 10.4% of those receiving iodixanol 320 (Visipaque ) (p < 0.01).
Conclusion: The incidence of early adverse reactions is similar with these 3 contrast agents. However, late skin reactions are significantly more common with iodixanol 320 (Visipaque ) than with the other 2 agents. Although such reactions were rarely troublesome, patients should be advised accordingly.