Background: Experimental and preliminary clinical data in patients with dilated cardiomyopathy show that growth hormone has a positive inotropic effect and contributes to peripheral vasodilatation. However, there is little information about the activity of growth hormone-IGF-1 axis in patients with chronic heart failure.
Aim: To measure growth hormone and IGF-1 levels in patients with chronic heart failure.
Patients and methods: Nine patients, aged 49 to 76 years old, 7 male, were studied. Seven had an idiopathic dilated cardiomyopathy and 2 a coronary heart disease. All had a stable cardiac failure, in functional capacity II or III and were receiving digoxin, furosemide and potassium supplements. Thyroid hormone levels, basal and exercise growth hormone and IGF-1 levels were measured and compared with reference values for American populations. Left ventricular ejection fraction was measured with an isotopic technique and nutritional status using anthropometry and indirect calorimetry.
Results: Anthropometric measures, basal and post-prandial oxygen consumption were within normal limits. Thyroid hormone levels were normal. During maximal exercise, growth hormone levels were 2.56 +/- 4.1 ng/ml and IGF-1 levels were 0.56 +/- 0.61 mU/ml. These values were significantly lower than expected for age and sex.
Conclusions: These patients with chronic cardiac failure have lower than normal growth hormone and IGF-1 levels.