[Early and late damage in bypass vessels induced by crystalloid and cardioplegic solutions].

Veins and arteries grafted into the aorto-to-coronary position undergo degenerative processes, subintimal fibrous hyperplasia and diffuse atherosclerosis. We examined the influence of various crystalloid and cardioplegic solutions on the endothelium of human saphenous veins and internal mammary arteries, bovine internal mammary veins and arteries and rabbit carotid arteries, using light microscopy, TEM, SEM, immunological techniques and quantitative permeability measuring methods. Immersion or perfusion of vessel segments for various periods of time led to an ultrastructural endothelial cell damage, to an increased endothelial permeability for macromolecules, partly to an endothelial cell loss. Addition of high concentrations of heparin impaired this effect. Under influence of various solutions an increased plaque development under stimulation with atherogenic stimuli was observed.