The effects of cardiopulmonary bypass on androgen hormones in coronary artery bypass surgery

The effects of testosterone on coronary vasomotor regulation have been described by several recent reports. Here we investigated changes in serum androgen levels during and after cardiopulmonary bypass (CPB) in patients who had undergone coronary artery bypass surgery. Serum luteinizing hormone, free testosterone and dihydroepiandrestenedione sulphate (DHEA sulphate) levels were evaluated in 38 male coronary artery bypass surgery patients using a chemical immunoassay technique. All hormone levels were corrected to account for haemodilution. Serum-free testosterone level decreased significantly during weaning from CPB (from 15.7 +/- 4.2 nmol/l to 6.2 +/- 2.8 nmol/l), and an even greater decrease was observed in the first post-operative day (5.4 +/- 3.1 nmol/l). On the seventh post-operative day, free testosterone levels reached a normal value (11.8 +/- 5.5 nmol/l), although they were still significantly lower compared with the pre-operative value. There were slight alterations in serum DHEA sulphate levels, although the only significant decrease occurred from the first to the seventh day post-operation (from 4.7 +/- 2.2 pmol/l to 3.7 +/- 1.8 pmol/l, respectively). Serum luteinizing hormone levels were decreased during weaning from CPB (from 4.8 +/- 2.1 mIU/ml to 3.9 +/- 1.8 mIU/mI), but increased rapidly to the pre-operative value (5.5 +/- 2.5 mIU/ml) at the first post-operative day. These results show that CPB affects serum luteinizing hormone, free testosterone and dihydroepiandrestenedione sulphate levels. The free testosterone level decreases significantly both during and after CPB surgery.