[Pattern of the coronary endothelium in the human]

The ultrastructural morphology of the endothelium of the normal human coronary arteries is equal to the endothelial cells of other locations in the macrovascular system. However, the patterns of the endothelial nuclei and the endothelial cell shape are consistent with unidirectional laminar blood flow conditions lacking secondary flow phenomena in this particular part of the arterial tree. On the other hand secondary flow probably occurs in areas of sclerotic plaques and a "cobblestone" pattern of the endothelial layer is often found at such places. In addition, multinuclear giant cells which might be of a heterogeneous origin, as well as other non-endothelial cells are a regular constituent of the endothelial layer of sclerotic lesions in the human coronary arteries.