What is a coronary artery stent procedure?

A small metal tubular structure called a stent is inserted into a coronary artery through a catheter under local anesthesia.  The coronary arteries supply blood flow to the heart muscle.  At the time a coronary stent is deployed, blockage in the artery is dilated with the balloon on which the stent is mounted. The stent acts as scaffolding, keeping the artery stretched open and maintaining adequate blood flow through the vessel. The procedure has a very high initial success rate, much better than just the balloon procedure by itself, but careful follow up is needed after a coronary stent procedure.

When does a patient’s condition require coronary stenting?

When coronary artery disease (CAD) has caused enough narrowing or blockage in a coronary artery so that blood supply to part of the heart is significantly limited, serious problems may occur. Symptoms accompanying this condition often include recurrent chest pain or pressure (angina) and shortness of breath upon exertion, or there may be no symptoms. CAD is the condition that causes heart attacks.

What tests can determine a need for coronary stenting?

Electrocardiogram (EKG/ECG) is a recording of the heart’s electrical activity. It may detect heart rhythm irregularities, disease and damage. Echocardiogram (sonogram of the heart) uses sound waves to evaluate the structure and function of the heart. It provides a moving image that allows your cardiologist to study the heart’s size, strength, and function and the valves of the heart.

A nuclear stress test involves the injection of a small, harmless amount of a substance with special (radionuclide) properties. This test provides images of the heart muscle with and without exercise or chemical stress to evaluate the blood supply to the heart muscle, and the strength of the heart. There are other types of stress tests that are also sometimes used for this purpose. In order to determine whether the blood supply to the heart is adequate, some kind of stress test is necessary.  The stress nuclear study is widely regarded as being one of the most accurate stress tests available.

A coronary angiogram, or arteriogram, is an actual picture of the inside of the arteries to the heart and is used to pinpoint the location and severity of CAD. It is an invasive procedure that involves insertion of a catheter, usually through a leg artery, all the way into the vessels of the heart where contrast medium is then injected and x-rays are taken to reveal pictures of the vessels.  Because of the invasive nature of this procedure, it is not used routinely to follow the condition of patients with CAD and is reserved for special circumstances, especially when the diagnosis is in question or a need to open a blockage in an artery appears to be present, including prior to a stent procedure.

How is coronary stenting performed?

Coronary stenting is a catheter-based procedure. The catheter acts as a guide to place the stent in the coronary artery to open a narrowing or blockage. Stents come in a variety of strengths, sizes, and other properties.  Some stents are coated with a drug that markedly improves the chances of a long-term success, but these stents also require careful follow up. Stent selection for each procedure depends upon many factors, including the size of the artery, the location of the blockage, the extent of that blockage and blockages in other arteries, and the strength of the heart muscle.

What should be expected after coronary stenting?

Coronary stents are exposed to the blood and may cause clots to form until they become covered with tissue by the body. Anticoagulants are taken during this time, and possibly longer, to prevent thrombosis (formation of blood clots). Check your anticoagulant therapy section below to determine what your cardiologist has prescribed for you to follow.  Aspirin and Plavix are almost always prescribed after coronary stenting.

Sometimes coronary stents re-narrow (restenosis) within six to eight months of placement. Because of the possibility of restenosis, your cardiologist will want you to follow-up with a preplanned diagnostic testing schedule. Your testing and follow-up schedule is shown below. Call your cardiologist’s office to schedule any that are not yet arranged. Follow-up is vital to early detection of new disease or re-narrowing of the stents.

The usual recommendation for coronary stent follow up is a stress nuclear study at:

• at 4-6 weeks
• at 6 months & 12 months
• then annually

Your cardiologist may request other tests depending on your condition.