Heart bypass surgery creates a new route, called a bypass,
for blood and oxygen to reach the heart.
Heart bypass surgery begins with an incision in the chest,
and the breastbone is cut exposing the heart.
Next, a portion of the saphenous vein, which is very large,
is harvested from the inside of the leg.
Pieces of this large vein are used to bypass the blocked coronary arteries,
which are arteries that supply blood to the heart.
The venous graft is sewn to the aorta, the main artery of the body,
and to the affected coronary artery, to bypass the blocked site.
The internal mammary artery from the chest
may also be used to bypass a clogged artery.
Several arteries may be bypassed depending on the condition of the heart.
After the graft is created, the breastbone and chest are closed.