Fluorine-18 FDG myocardial positron emission tomographic findings before and after pituitary adenoma resection in a patient with acromegalic cardiomyopathy.

Because of persistently elevated growth hormone levels, acromegaly gives rise to various changes in organs mediated by insulin-like growth factor-I. In the heart, it causes myocardial hypertrophy, and, with time, heart failure. The authors performed pituitary adenomectomy in a patient with acromegalic cardiomyopathy who had heart failure; after operation, the blood growth hormone levels decreased to within the normal range and there was a marked improvement in left ventricular function by gated blood pool scintigraphy. Pre- and postoperative fluorine-18 fluorodeoxyglucose (FDG) myocardial positron emission tomography showed increased accumulation of FDG in the myocardium before surgery, but accumulation within the normal range after operation. Myocardial glucose metabolism changed when the long-term effects of growth hormone and insulin-like growth factor-I were eliminated, and this appears to be accurately reflected by FDG positron emission tomography.