Histopathology of Thalassemic Heart Disease: An Endomyocardial Biopsy Study

Right ventricle endomyocardial biopsies were obtained from 13 thalassemic patients. Clinical profiles were investigated, and serum ferritin tests were assessed using diagnostic kits. Histochemical iron detection (Perls method) and immunohistochemical stain for ferritin were performed in the endomyocardial samples. Histologic iron overload was observed in eight patients, and variable iron deposits were recognized by a semiquantitative method. There was a statistically evident correlation between serum ferritin and myocardial iron storage. Marked iron deposition was associated with higher immunohistologic ferritin concentration. Iron-negative tissue samples showed bland immunohistochemical positivity. Myocardial interstitial fibrosis was observed in 12 cases; diffuse perimyocytic or perivascular fibrosis and endocardium thickening were the main histologic patterns identified. One biopsy was characterized by marked fibrolipomatous infiltration. Myocyte hypertrophy, myocytolysis, and severe capillary congestion also were observed.