The Surface Morphology of the Infundibular Muscle in Patients with Tetralogy of Fallot

The surface morphology of the infundibular muscles obtained from open heart surgery was investigated in 10 patients with tetralogy of Fallot. Various degrees of abnormal surface morphological changes were observed from the endocardium to the myocardium. In the endocardium striking proliferation of the endothelial cells was usually accompanied by focal loss of the endothelium with fibrotic change. Based on the characteristic alterations of the surface morphology 4 different groups of myocardial cells could be identified: normal myocytes, defective myocytes, sclerotic myocytes, and necrotic myocytes. Because intact surface morphology is responsible for integrated cellular function these pathological findings observed on the surface morphology of the endocardium and myocardium can provide a valuable reference to further understanding of functional disorders of the infundibular muscle in patients with tetralogy of Fallot.