Heparin in angiography: current patterns of use.

All members and fellows of the Society of Cardiovascular and Interventional Radiology were surveyed to determine current patterns of heparin use in angiography. Five hundred responses (68%) were received. In general, significant differences exist across the United States in the mean heparin dose for angiography, mean dose for angioplasty, heparin concentration in flush solutions, and, especially, frequency with which heparin is mixed with nonionic contrast media. Few respondents routinely use systemic (bolus) heparinization for angiography. Heparin concentration in flush solutions varies from 0 IU/L to 12,000 IU/L. Eleven percent of respondents mix heparin with nonionic contrast agents, at a median dose of 5 IU/mL. Results of this survey reveal patterns of practice but do not represent a standard of practice. Protocols for heparin use should be based on experimental evidence, and heparin dosage must be individualized for each procedure and each patient. Large-scale, prospective studies of the merits of systemic heparinization and of mixing heparin with nonionic contrast agents are needed.