Hypothyroid cardiomyopathy due to hypopituitarism: a diagnostic dilemma.

A case of hypothyroid cardiomyopathy secondary to hypopituitarism posed a diagnostic challenge. This lesson describes the patient's presentation with simultaneous acute heart failure and neurological signs; the investigations and imaging findings which initially suggested myocardial infarction (MI) and/or infiltration; and the response to treatment, with biochemical, sonographic and clinical resolution of the cardiomyopathy following thyroxine replacement therapy. This lesson illustrates the cardiovascular sequelae of severe hypothyroidism, and physicians are reminded of the difficulties involved in investigating putative coronary events in hypothyroid patients, since hypothyroidism itself may mimic MI.