An 11-year-old boy in acute adrenal crisis was subsequently diagnosed with Addison's disease and presumably had an unrecognized preceding chronic adrenal insufficiency. His adrenal insufficiency and hypovolemic shock were promptly diagnosed and treated in the emergency room. However, 24 h later, signs of congestive heart failure developed and an echocardiogram revealed cardiomyopathy. He responded to i.v. dopamine and his cardiomyopathy resolved over some days. Acute adrenal insufficiency and actual ventricular dysfunction had not been described in humans until last year; this is the second reported case of cardiomyopathy in a patient with acute adrenal insufficiency.