Hypertrophic Cardiomyopathy - HCM - LAMP2

This transmission electron micrograph shows an inclusion from a patient with cardiomyopathy with glycgoen storage in the myocytes and a LAMP2 mutation. The eosinophilic inclusions seen on H&E light microscopy are made of phagolysosomes (shown in the inset of this micrograph. In addition there is abundant free glycogen in the myocyte sarcoplasm in this image. The Glycogen granules appear as dark electron-dense alpha particles surrounding the inclusion and spreading between the myofibrils.