Progressive hemochromatotic cardiomyopathy despite reversal of iron deposition after liver transplantation

Dilated cardiomyopathy is a frequent and serious complication of idiopathic hemochromatosis. The mechanism by which disordered iron metabolism induces heart failure is not entirely understood, but myocardial dysfunction appears to be intimately related to the deposition of iron in myocytes. Cardiac function characteristically worsens or improves in proportion to the degree of iron accumulation in cardiac myocytes. The authors report the case of a 47-year-old man with idiopathic hemochromatosis and cirrhosis who developed symptoms of congestive heart failure and was found to have dilated cardiomyopathy 7 months after receiving a liver transplant. An initial endomyocardial heart biopsy demonstrated severe iron deposition in myocytes. The patient's heart failure worsened in the next 3 years and he eventually required a heart transplant. Examination of the explanted heart revealed dilated cardiomyopathy, but the previously demonstrated iron deposits in the cardiac myocytes were depleted. This 'uncoupling' of cardiac function and cardiac iron load suggests that a threshold may be reached at which point the metabolic and ultrastructural derangements of iron deposition are no longer reversible, even with the removal of the inciting agent. Furthermore, displacement of myocyte iron stores after liver transplantation implicates altered hepatic iron metabolism as a primary or contributing mechanism in the pathophysiology of idiopathic hemochromatosis.