Recombinant growth hormone therapy in patients with ischemic cardiomyopathy -: Effects on hemodynamics, left ventricular function, and cardiopulmonary exercise capacity

Background-We studied the effects of recombinant growth hormone (rhGH) on exercise capacity and cardiac function in patients with ischemic cardiomyopathy. Methods and Results-Seven patients (aged 55+/-9 years) with mild to moderate congestive heart failure (ejection fraction 31+/-4%) who were on standard therapy were included. The patients were studied at baseline, after 3 months of rhGH treatment, and 3 months after rhGH discontinuation. Cardiac function was assessed by exercise capacity, right heart catheterization at rest and after submaximal exercise, MRI, echocardiography, and Holter monitoring. When administered at a dose of 2 IU/d, rhGH doubled the serum concentration of insulin-like growth factor-I. rhGH improved clinical symptoms and exercise capacity significantly (New York Heart Association class 2.4+/-0.5 initially versus 1.4+/-0.5 at 3 months [mean+/-SD], P<0.05; (V) over dot o(2)max 13.6+/-3.8 versus 17.4+/-5.4 mL.kg(-1).min(-1), P<0.05). Additionally, pulmonary capillary wedge pressures at rest and after submaximal exercise were reduced significantly. Cardiac output increased, particularly at rest (5.0+/-1.1 versus 5.8+/-1.3 L/min; P<0.05). Posterior wall thickness was increased (1.08+/-0.1 versus 1.24+/-0.3 cm; P<0.05), and the end-diastolic and end-systolic volume indexes decreased significantly after rhGH treatment. There was no significant increase in left ventricular ejection fraction. The improvements were partially reversed 3 months after rhGH discontinuation. Conclusions-The administration of rhGH for 3 months in patients with ischemic cardiomyopathy results in significant improvement in hemodynamics and clinical function. The attenuation of left ventricular remodeling persisted 3 months after discontinuation of treatment.