Gadopentetate dimeglumine and iodinated contrast media: Hemodynamic side effects after bolus injections in pigs

RATIONALE AND OBJECTIVES. The use of bolus injections of contrast media containing gadolinium for magnetic resonance imaging and their potential use as x-ray absorbents require the evaluation of possible cardiovascular side effects. The hemodynamic reactions of high doses (0.6 mmol/kg) of gadopentetate dimeglumine (gadolinium [Gd]-DTPA, Magnevist) were evaluated and compared with the side effects of ionic (diatrizoate: Urografin 76%) and nonionic (iopamidol, Solutrast 370) radiographic contrast media. METHODS. In 18 pigs, pressure and flow of the systemic and pulmonary circulation were monitored after intracardiac bolus injections (2-4 seconds) of dose volumes of 1.2 mL/kg of each contrast agent. RESULTS. All contrast media decreased the aortic pressure transiently (Gd-DTPA and diatrizoate: -25%, iopamidol: - 10%; P < 0.01). Pulmonary artery pressure, cardiac output, and stroke volume increased for several minutes. The vascular resistance declined. Diatrizoate induced stronger and longer-lasting side effects (P < 0.01) than Gd-DTPA and iopamidol. CONCLUSIONS. Despite of similar osmolality, Gd-DTPA induced weaker side effects than equivolumetric applications of diatrizoate. Other than osmolality, other factors such as viscosity and chemotoxicity influence the side effects of contrast media.