Coronary hemodynamics during left and right coronary arteriography with an ionic and nonionic contrast medium

Abstract

Summary:The direct effects of ionic amidotrizoate (iodine content 370 mg/ml, osmolality 2.1 osmol/kg) and nonionic iopamidol (iodine content 370/ml, osmolality 0.8 osmol/kg) on the coronary circulation were intraindividually compared in 10 patients suffering From coronary heart disease. In accordance with a double-blind, crossover protocol, both contrast media were injected into the left and right coronary arteries (8 ml and 5 ml per injection, respectively). Injections of both dyes into the left coronary artery caused a similar decrease in heart rate. The prolongation in the QT interval was significantly greater after amidotrizoate (p <0.05). Systolic (p <0.01) and diastolic (p<0.05) aortic pressures decreased to a greater extent following amidotrizoate injection. Each contrast agent produced a similar increase in coronary sinus flow, but iopamidol resulted in a smaller decrease in coronary vascular resistance @< 0.05). After right coronary artery injections, both contrast media caused bradycardia and prolongation of the QT interval, a decrease in systolic and diastolic aortic pressure, a rise in coronary sinus flow, and a lowering of coronary vascular resistance. Though most changes were more pronounced following amidotrizoate injection, the differences in the ionic and the nonionic agent were not statistically significant. Thus, after selec- tive coronary arteriography , both contrast media caused a transient drop in coronary vascular resistance and a rise in coronary sinus flow despite a decrease in aortic pressure. The effects of amidotrizoate were more marked, which might be attributed to the higher osmolality of this ionic contrast medium. Coronary hemodynamics, however, usually returned to baseline values within 1 minute. The clinical significance of the differences in the ionic and nonionic agents appears questionable.