Electron microscopic examination of the patients with left ventricular hypertrophy and IVS4 + 919G > A mutation. Electron microscopic findings of the cardiomyocytes from patient no. 20 showed abundant membrane-bound lamellar myelin bodies (“zebra” or “onion-skin” appearance) (arrow) in this figure (A). The myelin bodies (arrow) were also found in most of the patients who received biopsy in this study. Further examples were showed in figure (B) (patient no. 8) and (C) (patient no. 2). Focal loss of myofilament (myofibrillolysis) (arrow), which may be attributed from glycosphinogolipid accumulation and was found in 14 out of 22 case, is presented in figure (D) (patient no. 4). No Gb3 accumulation was found in the capillary endothelium of all these patients. The endothelium (the arrow) were presented in figure (E) (patient No. 2) and (F) (patient No. 3). The scale bars = 2 μm.