The physical examination is surprisingly benign even in patients with heavy cardiac iron deposition. Once evidence of cardiac failure appears, however, heart function rapidly deteriorates, often without response to medical intervention. Biventricular failure produces pulmonary congestion, peripheral edema, and hepatic engorgement. This potentially lethal cardiac complication has been reversed on occasion by vigorous iron extrication. Iron deposition in the Bundle of His and the Purkinje system impairs signal conduction from the atrial pacemaker to the ventricles.
Patients sometimes die suddenly, presumably due to arrhythmias.
Reports of sudden death prompted cessation of this practice. Echocardiography in children and radionuclide ventriculography in adults are the most useful non-invasive diagnostic techniques. The echocardiographic abnormalities correlate roughly with the number of transfusions. Exercise radionuclide ventriculograms are particularly sensitive in the detection of cardiac dysfunction in patients with iron overload. The degree to which aggressive chelation therapy can reverse cardiac dysfunction has been a subject of vigorous debate.