Normal cardiac physiology: A background for understanding the cardiac effects of growth hormone

Cardiac pump performance, which is measured as cardiac output (the product of stroke volume and heart rate), can be significantly affected by growth hormone (GH) deficiency or excess. All of the determinants of stroke volume including preload, afterload, contractility and diastolic function are individually affected by GH. Recent data suggest that replacement therapy in GH-deficient patients may reduce the incidence of cardiac morbidity and mortality. Also, new studies are emerging which suggest that GH may be an important new adjunctive therapy for the treatment of heart failure. Thus, this article provides a brief overview of normal cardiac physiology and cardiac pump performance as a background for understanding the cardiac effects of GH and the implications of GH administration in patients.