Effects of Synthetic Blood Combined with Contrast Medium on Coronary Endothelium: An Experimental Study

The study described was carried out to evaluate endothelial injury following incubation of coronary material in contrast medium and in contrast medium diluted with fluorocarbon solution. Six porcine hearts were excised and isolated. Immediately thereafter, pieces of the main coronary arteries and ascending aortas were incubated in four different solutions: 1) blood, 2) contrast medium, 3) fluorocarbon solution, 4) fluorocarbon — contrast medium (1:1). Flow surfaces and coronary endothelial morphology were evaluated by scanning electron microscopy (SEM). Porcine blood (at room temperature) preserved endothelial structures intact but, in two samples, small patchy areas of denuded surface were found. Four minutes' immersion in contrast medium resulted in easily visible changes in the endothelial lining and individual cells. Denuded flow surface areas were common, the intact surface morphology was flattened. After 7 minutes, destruction was total. The addition of fluorocarbon solution to contrast medium (1:1) diminished the changes, which also occurred later than after incubation in pure contrast medium. After 7 minutes, separate endothelial cells were still identifiable but the microvilli had disappeared. Fluorocarbon solution preserved the endothelial lining well during a 10-minute follow-up period. The experimental protocol described confirmed the deleterious effect of con-trast medium on coronary endothelial lining, which could be reduced to some extent by adding fluorocarbon solution to contrast medium.