You may have heard that many heart surgeons harvest and use a patient’s very own great saphenous vein from their leg when performing bypass surgery on that patient. http://www.humanbodyhelp.com/blood-vessel-plaque-lower/ (#6 on the picture) Doing this has been a common practice for years. You may even have a grandparent who has a long scar on their leg where their great saphenous vein was retrieved for their surgery.
Did you know, the great saphenous vein is not the only option for bypass surgery? Some surgeons prefer to use the internal thoracic artery, a branch of the subclavian artery located just lateral to the sternum inside the ribcage. http://www.humanbodyhelp.com/wire-blood-vessel-model-upper/ (#7 on the picture) One reason this may be a better option could be the internal thoracic artery is around the same size as a coronary artery, so it’s a nice “apples to apples” exchange. Also, the internal thoracic artery is an artery, with thicker walls than a vein, so it’s more likely to hold up to the higher blood pressure inside the arteries. Finally, the internal thoracic artery is easy to harvest in a relatively short amount of time once the chest is opened for bypass surgery. Harvesting of the great saphenous vein requires an additional surgery.
This YouTube video shows just how easy it is to surgically harvest an internal thoracic artery. (Caution: the video is graphic!) https://www.youtube.com/watch?v=qDaaPKhwdy0&t=317s
This YouTube video shows the surgical procedure to harvest a great saphenous vein: (Caution: the video is graphic!) https://www.youtube.com/watch?v=JNVk1BRKjN0