SFA blood test is widely used to eliminate plaque lie inside the female artery. SFA stands for Superficial Femoral Artery which is basically a blood vessel that escorts oxygen and blood in to the human legs. The plaques formed inside the body can be in the form of excessive fat, cholesterol which reduces the blood flow to the legs. Doctors usually diagnose the SFA tests to those individuals who claim to have problems in their blood passage towards their leg or suffer from plaques found in the body.