Risk of thrombogenicity among nonionic radiocontrast agents

Several contrast agents have been approved in the United States for radiographic imaging purposes. Most of the older ionic, high-osmolar contrast agents are no longer used because of their side effect profile. Therefore, newer nonionic, low or iso-osmolar contrast agents have been widely accepted as an alternative due to their improved tolerability and safety. We investigated the thrombogenicity of the 6 different nonionic radiocontrast media in terms of their platelet reactivity and noted some minor differences among them. In the 50% contrast concentration group, all of the nonionic contrast agents inhibited aggregation, whereas in the 10% contrast concentration group, all agents showed similar aggregation curves in comparison to the normal control. At 50% contrast concentration, the inhibitory effect of aggregation appeared to be related to the inhibition of calcium mobilization, which may be one of the mechanistic effects.