A renal stent is a small wire mesh tube that is used to hold open a renal artery that has been narrowed by artery disease (atherosclerosis). The renal arteries are the blood vessels that branch off the largest artery in the body (the aorta). The renal arteries carry blood to the kidneys.

Atherosclerosis is a disease that affects the blood vessels. Atherosclerosis is caused by fatty, cholesterol deposits that begin within the blood vessel wall and eventually progress to cause narrowing of the blood vessel itself. This narrowing can block blood flow through the artery.

To begin a renal stenting procedure, a thin guide wire is inserted into a small incision in the upper thigh. This process is usually visualized using x-rays and a special dye that helps reveal the arteries. This guide wire is carefully inserted into the femoral artery and guided through the aorta until it reaches the renal artery. Then a thin tube with a balloon at its tip (called a balloon catheter) is inserted over the guide wire until it reaches the renal artery. The balloon is then inflated inside the narrowed artery. This pushes the artery walls open and this is called angioplasty. The balloon is deflated and the catheter is removed. Another balloon catheter with a collapsed stent over the balloon is then inserted over the guide wire. Once in place, the balloon is inflated. The stent is expanded by the balloon. The balloon is deflated and the stent remains in place. The catheter and guidewire are then removed.