Right ventricular dysplasia: an ultrastructural study.

Ultrastructural observations on myocardial biopsies from patients developing clinical and/or echocardiographic and haemodynamic signs of dysplasia of the right ventricle did not reveal morphological defects of the myocardiocyte contraction apparatus, but showed evidence of fibrosis of the myocardial interstitium and modifications of the structures involved in the transmission of the action potential into the cardiac cells as well as of the junctional system between them. Interstitial adipocytes and intracellular lipid droplets were not increased in number.