Changes in cardiac muscle mass and function in hemodialysis patients during growth hormone treatment

Background: Adult patients with chronic renal failure (CRF) often show symp toms as fatigue, wasting, and reduced working capacity with concomittant fi ndings of reduced cardiac performance and muscle mass. This state may in pa rt be caused by an imbalance in the somatostatin/somatomedine axis resultin g in increased catabolism. During an attempt to correct this catabolic stat e by administration of exogenous growth hormone, cardiac muscle mass and pe rformance were studied. Methods: In a double-blind, placebo-controlled 6-mo nth study comprising 20 adult enfeebled hemodialysis patients, 9 patients w ere treated with a single daily subcutaneous injection of recombinant human growth hormone (rhGH) 4 IU/m(2) and 11 with placebo injections. Left ventr icular muscle mass (LVM) and ejection fraction (EF) were evaluated by echoc ardiography and the maximal working capacity (MWC) was measured by a bicycl e exercise test performed before and after the treatment period. Supplement ary electrocardiography (ECG) was performed before and after 6-month treatm ent. Results: Median LVM increased significantly from 172 to 220 g (p = 0.0 3) in the rhGH-treated group, while an insignificant decrease was observed in the placebo group from 281 to 200 g (p = 0.3). The EF showed no signific ant changes in the two groups. MWC showed a slight, insignificant decrease in both groups. From ECG no significant ST deviations were found and no sig nificant changes regarding B-Hb, blood pressure or pulse were observed in t he two groups. Irregular heart rhythm aggravated in one patient during the first month of treatment with rhGH, but was overcome by a -blocking agent. Conclusion The treatment with rhGH of adult chronic hemodialysis patients f or 6 months increased the left ventricular mass significantly, but without any effect on ejection fraction or maximal working capacity. No electrocard iographic signs of ischemia were associated with the increasing muscle mass and only one patient developed symptoms that might relate to ischemia. No changes in B-Hb, blood pressure or pulse were observed during the treatment period.