Vascular bypass

A vascular bypass (or vascular graft) is a surgical procedure performed to redirect blood flow from one area to another, in which a diseased artery is bypassed from an area of normal blood flow proximal to it, to another relatively normal area distally. It is commonly performed due to inadequate blood flow (ischemia) caused by vascular atherosclerosis or stenosis, or as a part of organ transplantation. In general, someone's own vein (autograft) is the preferred graft material (or conduit) for a vascular bypass, but other types of grafts such as polytetrafluoroethylene (Teflon), polyethylene terephthalate (Dacron), or a different person's vein (allograft) are also commonly used. Arteries can also serve as vascular grafts. A surgeon sews the graft to the source and target vessels by hand using surgical suture, creating a surgical anastomosis.

Common bypass sites include the heart (coronary artery bypass surgery) to treat coronary artery disease, and the legs, to treat peripheral vascular disease.

Cardiac bypass is performed when the arteries that bring blood to the heart muscle (coronary arteries) become clogged by plaque. Such a condition may cause chest pain from angina pectoris or a heart attack.

In the legs, bypass grafting is used to treat peripheral vascular disease, acute limb ischemia, aneurysms and trauma. While there are many anatomical arrangements for vascular bypass grafts in the lower extremities depending on the location of the disease, the principle is the same: to restore blood flow to an area without normal flow. For example, a femoral-popliteal bypass ("fem-pop") might be used if the femoral artery is occluded. Other anatomic descriptions of lower extremity bypasses include:

...
Wikipedia