Hypotestosteronemia is also suggested to be the result of advancing age, physiological stress due to major surgery (e.g., cardiac surgery), and the presence of cardiovascular disease. Data further suggest that elderly males with a history of depressed ejection fraction (<40%) placed on cardiopulmonary bypass for cardiac revascularization are at risk of subsequent declines in the production of both testosterone and somatomedin C [18,27]. This evidence concerns the gene IGF1 and cardiovascular disorder.