Abstract 16573: Dilated Cardiomyopathy Related to Pseudoacromegaly
Background: Pseudoacromegaly is a rare disorder characterized by tissue overgrowth and acromegaloid features in the absence of growth hormone (GH) or insulin like growth factor-1 (IGF-1) oversecretion. Cardiomyopathy is a known complication of acromegaly but an association with pseudoacromegaly has not been previously reported.
Case: A 22 year old male with hypertension and type II diabetes presented with dyspnea. His mother had gigantism and died in her 30s from heart failure. Physical examination revealed features of gigantism and acanthosis nigricans. His troponin I, BNP and ECG were unremarkable. An echocardiogram revealed a dilated left ventricle (LV end diastolic dimension (LVEDD) of 7.9 cm) and ejection fraction (EF) of 15%, noninvasive myocardial perfusion imaging was normal. His serum GH, prolactin, ACTH, TSH, cortisol levels and pituitary MRI were normal. Serum IGF-1 was low with elevated plasma fasting insulin and C-peptide. He was diagnosed with a dilated cardiomyopathy secondary to pseudoacromegaly. Following 3 months of treatment with beta blocker and angiotensin receptor blocker, his LVEDD decreased to 7.3 cm and EF improved to 30-35%.
Discussion: Pseudoacromegaly is rare disorder characterized by tissue overgrowth and acromegaloid features in the absence of GH or IGF-1 oversecretion due to supraphysiological insulin levels providing stimulus to growth through an intact mitogenic signaling pathway resulting in excessive acral growth and changes in tissue composition. An IGF-1 receptor mutation may also result in excess growth without high insulin level. Our patient had severe dilated cardiomyopathy diagnosed at a relatively early age with phenotypic features of gigantism. Based on clinical and biochemical features, and the absence of any other cause, the patient was diagnosed with pseduacromegalic cardiomyopathy. To our knowledge this is the first report of a patient with the rare disorder of pseudoacromegaly found to have a dilated cardiomyopathy. Management of heart failure in patient with acromegaly or pseudoacromegaly is not well established. In this case, a reduction in ventricular size and improvement in LV systolic function was achieved with neurohormonal inhibition.
Author Disclosures: S. Shah: None. S. Ganatra: None. D.M. Venesy: None.
- © 2014 by American Heart Association, Inc.