Ultrastructural aspects of subendocardial fat cells accumulation.

Nine cases of subendocardial fat cell accumulation were found in association with various heart diseases in adults. Morphological observations suggest that this lesion results from injury to myocardial cells resulting in accumulation and later extrusion of lipids. This evokes lipidophagy and transforms the phagocytizing macrophage into a preadipocyte-like and in turn adipocyte-like cell. Collagen production around the process depends upon the extent of myocardial damage and the intensity of removal of cell debris.