 A term that comes up with peripheral artery disease is intermittent claudication. An intermittent meaning of an on and for claudication just think about clouds. So peripheral artery disease is arthroesclerosis of the lower extremities. So now when the patient has a given amount of exercise that requires blood flow to the legs and that is now impeded by the arthroesclerosis by those blocked arteries. And therefore when they exercise, when they go a certain distance, the muscles cannot be fed with the blood flow that they would need causing symptoms, pain, cramping, maybe some discoloration of the lower extremities. And so this intermittent claudication many times can be resolved when the patient rests. And so the physician will usually determine the degree of the peripheral artery disease by the reports of the patient, how far can they walk and when do they develop symptoms and is it getting worse or is it staying the same. And then sometimes they have to look into other treatment options.