RESUMO
Right ventricular endomyocardial biopsy specimens from patients clinically diagnosed as having arrhythmogenic dysplasia of the right ventricle underwent electron microscopic and immunohistochemical studies. Myocardial fibrous fatty dysplasia was found in the semi-thin sections. The TUNEL immunohistochemic test revealed apoptotic nuclei in the cardiomyocytes. In the binucleated and trinuclated cardiomyocytes, one or two nuclei might be apoptotic, one or two others nuclei being intact. Electron microscopy identified the stages of movement of cardiomyocytic nuclei to the cell periphery as well as nuclear extrusion outside the cardiomyocytes. The cardiomyocytes themselves displayed pronounced vacuolization, mitochondrial destruction, accumulation of lipid inclusions and lysosome-like masses, and myofibrillar destruction.
