A cardiovascular stent is a medical device used to keep arteries and vessels that are blocked open so blood flow is not restricted. There are three types of stents commonly used as of 2011: drug-eluting, bare metal and stent grafts. The procedure for placing a cardiovascular stent normally is done as an outpatient procedure.
A catheter is used to insert a cardiovascular stent into an artery. Stents can be used in the coronary arteries of the heart, the carotid arteries in the neck, or in the leg veins of patients who suffer from peripheral artery disease (PAD). For those who have heart disease, cardiovascular stents not only increase the chances that a patient will survive if he has a heart attack but also reduce chest pain. A patient who is at a high risk for a stroke can greatly lower that risk if stents are placed in the carotid arteries so blood flow to the brain is not affected. An aneurysm, caused by a weakened blood vessel that leaks blood into the surrounding tissue, can be treated using stent grafts that will strengthen the blood vessels.
A bare metal cardiovascular stent is made of metal. This was one of the first kinds of stent. These stents can become blocked with scar tissue, and blood clots also can form in and around bare metal stents.
Drug-eluting stents were made to reduce the problems that occur with bare metal stents. This kind of cardiovascular stent releases an antiproliferative drug in small amounts. The drug reduces the amount of scar tissue and helps keep the arteries clear.
Stent grafts are stents made of special fabric. The fabric is attached to a metal support so the stent graft will hold its shape. These types of stents are some of the newest ones available.
A cardiologist inserts a cardiovascular stent using a catheter. A small incision is made in the groin area and the catheter is threaded through the blood vessels to the site of the blockage, much like an angioplasty procedure is done. In the U.S., a balloon is used to open the blocked artery, then the stent is threaded through to the area and expanded to fit the artery. It is common practice outside the U.S. simply to thread the cardiovascular stent through the blockage and expand it. Patients are kept overnight for observation and are periodically checked to make sure there are no blood clots or new blockages.