Final answer:
When the saphenous vein is not available for coronary bypass, other graft options include the radial artery, internal mammary artery, gastroepiploic artery, inferior epigastric artery, deep femoral vein, small saphenous vein, and femoral circumflex vein.
Step-by-step explanation:
During coronary bypass surgery, if the saphenous vein is not used, several other vessels can be harvested to create a bypass around occluded coronary arteries. Alternative vessels that may be used include the radial artery, which is generally taken from the forearm, and the internal mammary artery (also known as the internal thoracic artery), which is located in the chest wall. Additionally, the gastroepiploic artery from the stomach and the inferior epigastric artery from the abdominal wall may be considered for grafting.
Vessels such as the deep femoral vein, small saphenous vein, and femoral circumflex vein are also potential options, especially for venous grafts. Since the body has a network of veins, called anastomoses, removal of certain superficial veins typically does not impair circulation.