The purposes of this protocol are two-fold: 1) to determine whether deferoxamine, given subcutaneously on a regular basis, can indefinitely prevent the cardiac, endocrine and hepatic complications of transfusional hemochromatosis; and 2) to determine whether cardiac disease can be reversed by intensive intravenous treatment in patients who already have objective evidence of cardiac dysfunction. The clinical manifestations and course of patients who require regular blood transfusions is well established. Those with congenital anemias who require transfusions from birth develop cardiac disease in their teens and their mean of survival is only 17 years. Adults with acquired anemias begin to exhibit cardiac manifestations of iron deposition after 100-200 units of packed red cells. Deferoxamine, when given by the subcutaneous route, has been shown to reduce substantially the total iron burden in thalassemic patients. Our results indicate that cardiac complications are delayed or prevented. We plan to continue to follow our cohort of patients on optimal medical management to determine if chelation alters disease outcome. Patients with heavy iron burdens who already manifest cardiac disease will be chelated intensely to determine whether reducing the iron burden is associated with reversal of cardiac complications.