Partial blockage of arteries due to atherosclerosis, hardening of the arteries, can cause many health problems including high blood pressure and stroke. Each year in the United States, approximately 795,000 people have strokes and approximately 20% of these strokes can be attributed to atherosclerosis in the carotid arteries, which run through the neck to the brain. Atherosclerosis can also lead to partial blockage of the arteries that go to the kidneys. This disorder has been reported in 6.8% of the Medicare population and it can cause elevated blood pressure. Catheters can be used to push open arterial blockages and to deliver stents that help keep arteries open; however, the atherosclerotic material causing the blockage can break up while it is being manipulated by the catheters, generating fragments that can travel to and damage the brain, kidneys, and other organs.