ACUTE HEMODYNAMIC-EFFECTS OF RECENTLY DEVELOPED MONOMER AND DIMER MAGNETIC-RESONANCE-IMAGING CONTRAST-MEDIA - A COMPARATIVE-STUDY

Rationale and Objectives. We evaluated and compared the acute cardiova scular effects of equiosmolar doses of recently developed nonionic mon omer and macrocyclic dimer magnetic resonance (MR) imaging contrast me dia with the clinically available ionic and nonionic MR contrast media . Methods. Normotensive adult Sprague-Dawley rats were divided into si x groups of seven rats per group. Group 1 received the nonionic monome r Gd-CMPA-BMPA (500 mmol/l solution); group 2 received the nonionic di mer Gd(2)2(O)DO3A (500 mmol/l solution); group 3 also received Gd(2)2( O)DO3A but at a higher concentration (1,000 mmol/l solution); group 4 received gadopentetate dimeglumine (500 mmol/l solution); and group 5 received gadodiamide (500 mmol/l solution). Each rat received a rapid (1-2 sec) bolus intravenous injection of 0.1, 0.25, and 0.5 mmol/kg of each contrast agent. Group 6 was used to test the peak effects of equ iosmolar glucose solutions (500, 1,000, and 2,000 mOsm/kg water), Data were acquired at baseline, 20 sec (peak effect) after injection, and 1, 3, 5, and 10 min after injection. Peripheral (systolic, diastolic, and mean) pressure, central venous pressure; left ventricular (LV) pre ssure (peak systolic and end diastolic) pressure, first derivative of left ventricular pressure (+/-dP/dt), rate pressure product, and heart rate were measured, Results. Bolus administration (0.1, 0.25, and 0.5 mmol/kg) of Gd-CMPA-BMPA and gadodiamide (500 mmol/l) had no signific ant effects on the monitored cardiovascular parameters. Bolus injectio n of 0.25 and 0.5 mmol/kg Gd(2)2(O)DO3A (500 and 1,000 mmol/l) and gad opentetate dimeglumine (500 mmol/l) caused transient cardiovascular de pression, including decreased peripheral blood pressure, LV systolic p ressure, peak positive and negative dP/dt, and rate pressure product, but an increased LV end diastolic pressure. These cardiovascular effec ts were slightly less profound than those produced by gadopentetate di meglumine. Conclusion. Gd-CMPA-BMPA and gadodiamide have no adverse ca rdiovascular effects, Gd(2)2(O)DO3A and gadopentetate dimeglumine caus e vasodilation and reduced cardiac performance. Therefore, presuming s imilar effects, if Gd(2)2(O)DO3A and gadopentetate dimeglumine are to be used at high doses for the MR quantification of blood volume or as a bolus for perfusion study, appropriate consideration should be given to possible adverse physiologic changes.