Narrowing or blockage in the arteries is most often caused by atherosclerosis, also called hardening of the arteries. Although it is commonly thought of as a heart disease, atherosclerosis can affect arteries anywhere in the body, including the legs and the brain. It is a gradual process in which cholesterol and other fatty deposits-called plaques-build up on the artery walls. These plaques act as barriers that limit blood flow through the arteries to tissues and organs. Other barriers to adequate blood flow include clots or plaques that break away from the blood vessel wall and become lodged in an artery.

When a blood clot, plaque or scar tissue cause an artery to become narrow or completely blocked, blood circulation is limited and the organs and tissues supplied by that artery do not receive enough oxygen.

Angioplasty and vascular stenting are commonly used to treat conditions that result when arteries throughout the body become narrowed or blocked, including:

• Peripheral vascular disease (PVD)/peripheral artery disease (PAD) (narrowing of the arteries in the legs or arms).
• Renal vascular hypertension (high blood pressure caused by narrowing of the kidney arteries).
• Hemodialysis access maintenance.
• Coronary artery disease (narrowing of the heart arteries).

Angioplasty, also called balloon angioplasty, and vascular stenting are minimally invasive procedures performed by an interventional radiologist to improve blood flow in the body's arteries.

In the angioplasty procedure, the physician threads a balloon-tipped catheter-a thin, plastic tube-to the site of a narrow or blocked artery and then inflates the balloon to open the vessel. The balloon is then deflated and removed from the artery. Vascular stenting, which is often performed at the same time as an angioplasty, involves the placement of a small wire mesh tube called a stent in the artery. This may be necessary after some angioplasty procedures. The stent is a permanent device that is left in the artery.