Effect of viscosity and iodine concentration of nonionic radiographic contrast media on coronary arteriography in patients.

To assess the influence of viscosity and iodine concentration, three matched and standardized left coronary arteriograms were obtained in 20 patients using iopamidol (Isovue-370), ioversol (Optiray-320), and iohexol (Omnipaque-350). The order of contrast media was randomized and the administration of contrast was double-blinded. Quantitative densitometric angiographic evaluation of the coronary angiograms was performed in addition to independent operator qualitative assessment. The injection volume of iopamidol (5.4 +/- 1.0 ml) was slightly but significantly less than that of ioversol and iohexol (5.6 +/- 1.0 ml, 5.7 +/- 1.0 ml, both p less than 0.05). The calculated iodine concentration was also lower for ioversol (1.7 +/- 0.32 gm) than for iopamidol (1.98 +/- 0.35 gm) and iohexhol (1.9 +/- 0.35 gm, both p less than 0.05). There were significantly lower contrast syringe injection pressures for ioversol (6.6 +/- 0.8 atm) than for iopamidol (7.5 +/- 0.9 atm) and iohexol (7.2 +/- 1.1 atm, both p less than 0.05). The quantitative densitometric analysis failed to demonstrate significant differences among the contrast media with respect to image density parameters for any individual agent. All coronary angiograms were deemed of diagnostic quality. The data in this study indicated that although differences in iodine concentration exist among the three agents, operator compensation with more rapid contrast delivery (higher volume) and lower viscosity (lower injection pressure) produced equivalent image opacification during coronary angiography. Given the same incidence of adverse hemodynamic and clinical effects, selection of a low viscosity media theoretically provides an advantage during procedures using small diameter catheters or interventional procedures requiring contrast visualization through reduced catheter lumina.