Author
Julian M Aroesty, MD
Section Editor
Donald Cutlip, MD
Deputy Editors
Leah K Moynihan, RNC, MSN
Gordon M Saperia, MD, FACC



INTRODUCTION — There are two main types of treatment for people with angina (chest pain) caused by coronary artery disease: medications (medical therapy) and interventional treatment (treatment that opens or bypasses narrowed coronary arteries). The goals of these treatments are to improve a person's quality of life and to alleviate symptoms such as angina. In some people, these interventions may also delay or stop the progression of the disease and thereby prolong life.

This topic review discusses percutaneous coronary intervention, also called angioplasty. The other interventional treatment, coronary artery bypass graft surgery (CABG), is discussed in a separate topic review. (See "Patient information: Coronary artery bypass graft surgery".)

Medical therapy for coronary artery disease is discussed separately. (See "Patient information: Angina treatment — medical therapy".) A comparison of medical treatment and interventional treatment is also available. (See "Patient information: Angina treatment — medical versus interventional therapy".)

WHAT IS ANGIOPLASTY? — Angioplasty, also known as percutaneous coronary intervention, is a procedure that uses a flexible plastic catheter with a balloon at the end to dilate narrowed arteries in the heart. The procedure often includes placement of a metal stent to hold the artery open (figure 1). In this way, angioplasty helps to restore blood flow to the heart muscle.

Why do I need angioplasty? — Chest pain that originates from the heart muscle is called angina pectoris. Angina is a signal that the heart muscle is not getting sufficient blood flow, specifically sufficient oxygen. Lack of oxygen is termed ischemia. Blood flow is most often reduced by coronary artery disease (CAD), which causes a narrowing of the arteries that carry blood to the heart muscle (figure 2). Narrowing in the coronary arteries occurs as a result of calcium and fatty deposits, called plaques.

A person with narrowed arteries may develop angina during activity, exercise, or any other physical or mental stress that increases the heart's demand for blood. Angina can be "stable" or "unstable". Angina is unstable when there is a change in the usual pattern, such as a change in frequency, severity, duration, or precipitating cause. Unstable angina may be associated with damage to the heart muscle (or heart attack). The term acute coronary syndrome refers to people with unstable angina or a heart attack; these conditions require immediate evaluation in a hospital. (See "Patient information: Chest pain".) In severe cases, heart attack can lead to heart failure or sudden cardiac death.

Angioplasty candidates — Angioplasty may be recommended in addition to medical therapy for two groups of people with stable angina:

* People who have persistent and intolerable symptoms despite adequate medical treatment
* People who have specific patterns of arterial narrowing and a high risk of either a heart attack or death

The usefulness of angioplasty depends upon the severity of arterial narrowing. Angioplasty is often recommended when arterial narrowing is moderate to severe or when only one or two coronary arteries are severely narrowed. It may be less effective in patients who have diabetes. People with diabetes appear to have greater benefit from bypass surgery, especially if there are two or three vessels involved.

People who have extensive coronary heart disease, including a large number of narrowed coronary arteries or narrowing of the left main coronary artery and poor pumping function of their left ventricle (lower heart chamber), tend to live longer when they have coronary artery bypass surgery rather than medical treatment. (See "Patient information: Coronary artery bypass graft surgery".)

Angioplasty benefits — Angioplasty relieves angina and improve a person's ability to exercise. However, many individual factors influence the effectiveness of interventional treatment and its continued benefit over time. It is therefore important to discuss realistic expectations for each of these procedures with a doctor.

Angioplasty risks — Angioplasty is an invasive procedure and is associated with risks that should be discussed with a doctor. The extent of this risk depends upon many individual factors. (See 'Angioplasty complications' below.)

THE ANGIOPLASTY PROCEDURE

Preparing for angioplasty — Blood tests and an electrocardiogram (EKG) are usually performed before angioplasty. These tests help to ensure that other potential medical problems are identified and managed prior to angioplasty.

Coronary arteriography — Prior to angioplasty, testing is done to determine which coronary arteries are blocked and to evaluate the severity of the blockage. This procedure is called cardiac catheterization or coronary angiography. In patients with stable angina, it is usually performed in a hospital, often immediately before angioplasty.

Most patients are told not to eat or drink anything for 6 to 8 hours before the catheterization procedure. People with diabetes should speak to their doctor about how much medication to take before the procedure. Anticoagulant medications such as warfarin may be decreased or even stopped temporarily before surgery, depending upon the reason the anticoagulant is used. However, aspirin and an antiplatelet medication (eg, clopidogrel) are usually continued. It is important to follow all of the instructions regarding medication use before surgery; the procedure may need to be canceled or delayed if instructions are not followed exactly.

The patient is given a sedative and may be given a pain medication before the procedure. Most people do not remember the procedure as a result of these medications. A tiny catheter is inserted into an artery in the leg (the femoral artery) or in the arm (the radial artery). The catheter is moved through blood vessels to the heart. The coronary arteries are viewed by injecting a dye (contrast) through the catheter and using a type of x-ray machine (called a fluoroscope).

Based upon the results of this test, the doctor sometimes proceeds immediately with angioplasty if it appears reasonable to do so. "Reasonable" is determined both by the nature of the blockage and by the patient's wishes, which are usually discussed before the catheterization.

* In some cases, a procedure to treat the blocked or narrowed arteries (angioplasty) can be performed immediately following the catheterization.
* In other cases, treatment with medications is continued OR open heart surgery with bypass may be recommended. (See "Patient information: Angina treatment — medical therapy" and "Patient information: Coronary artery bypass graft surgery".)

How is angioplasty performed? — Angioplasty is usually performed in a hospital in an area called the catheterization laboratory. The procedure usually takes between one and two hours. The patient is given a sedative and pain medication before the procedure. Many people do not remember the procedure as a result of these medications.

To open the narrowed artery, a long, thin catheter with a deflated balloon at its end is inserted into an artery in the leg (the femoral artery) or the arm (the radial artery). The catheter is guided through blood vessels to the beginning of a narrowed coronary artery in the heart. The placement of the catheter is confirmed by injecting a dye into the coronary artery and using a type of x-ray machine (called a fluoroscope) to view the catheter's position.

The balloon is then inflated, which expands the narrowed artery. A stent (an expandable metal tube usually made of wire mesh) is often placed after the vessel is expanded to reduce the risk of narrowing in the future (figure 2). Some stents are coated with a medication (called drug-eluting stents) to help prevent the development of excessive tissue growth. This tissue forms in an effort to "heal" the stented area, however, it could potentially narrow or totally block the coronary artery over time.

Angioplasty complications — Complications of angioplasty are relatively infrequent. The most common complications include discomfort and bleeding at the puncture site where the catheter was inserted.

Occasionally, angioplasty creates a small tear (dissection) of an internal layer in the coronary artery. Usually, the tear is small and heals by itself. In some cases the tear is corrected with a stent. If the tear is severe, causing a blockage in blood flow in the artery or loss of blood around the heart, immediate treatment is given. This usually includes a repeat angioplasty and insertion of a stent. Rarely, a person will need urgent bypass surgery.

Approximately 10 percent of patients develop chest pain within 48 hours of their procedure. In some cases this pain is caused by a lack of oxygen in the heart (ischemia) that occurs when a small tear (dissection) develops or pieces of the plaque material travel downstream (embolization).

Many patients have evidence of a very small amount of heart damage after angioplasty, based upon blood testing. However, less than one percent of patients have a heart attack large enough to cause a substantial amount of damage.

Limitations of angioplasty — Although angioplasty restores blood flow and relieves symptoms in over 90 percent of patients, there is a risk of recurrent symptoms within six months, often due to recurrent narrowing (restenosis) of the artery. Restenosis that is severe enough to cause bothersome or life-threatening symptoms occurs in:

* Approximately 30 percent of people who have balloon angioplasty without stent placement.
* Approximately 15 percent of people who have a bare metal stent.
* Less than 10 percent of people who have a drug coated stent.

Some coronary artery sites are more prone to renarrowing than others. In addition, some conditions increase the risk of narrowing, potentially requiring a repeat catheterization and reopening or bypass of the narrowed artery:

* Diabetes
* Continued cigarette smoking
* High blood pressure
* Arteries that are narrow
* High level of bad (LDL) cholesterol
* Narrowing in a major blood vessel that is at or near the beginning of a side branch

Recurrent symptoms can develop as a result of other vessels that become narrowed. Some vessels that are very small, have longstanding total blockages, or have a very calcified (hardened) lesion cannot be adequately opened.

Care after the procedure — Following the angioplasty procedure, the catheter is removed from the artery and pressure is applied to the area. In some cases, a pressure device is used to limit bleeding from the site. In other cases the artery is sealed closed at the time the catheter is removed.

The patient must lie flat and remain still for several hours to reduce the risk of bleeding. During this time, the patient will remain in a recovery area where his or her blood pressure, heart rate, oxygen level, temperature, and puncture site can be monitored frequently. As the sedative medication begins to wear off, pain medication may be given if needed.

Most patients will remain in the hospital overnight after angioplasty. A friend or family member must be available to drive the patient home. Most patients are able to walk on the day after the angioplasty and can resume their normal activities, including returning to work, within a week. Driving and heavy lifting and pushing or pulling is not allowed for a few days. Specific activity restrictions should be discussed with a clinician.

When to seek help

Reference:
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