The heart and blood vessels comprise the two elements of the cardiovascular system that work together in providing nourishment and oxygen to the organs of the body. The activity of these two elements is also coordinated in the body's response to stress.
graft vs fistula. A graft is usually in a horse-shoe or letter C shape, and is normally firmer to the touch. Fistulas usually run up and down and are more squiggly shaped, with bumps (pseudo anurisms) and softer to the touch. Here are some good pics of fistulas. For some reason, I could not find any pics of grafts on the net.
A fistula is an abnormal anastomosis, that is, an abnormal connection between two hollow spaces (technically, two epithelialized surfaces), such as blood vessels, intestines, or other hollow organs. Fistulas are usually caused by injury or surgery, but they can also result from an infection or inflammation.