Worlds of David Darling
Encyclopedia of Science
   
Home > Encyclopedia of Science

angioplasty





Contents
  • When is coronary angioplasty done?
  • What are the risks?
  • What happens before coronary angioplasty?
  • What happens during coronary angioplasty?
  • What happens after coronary angioplasty?
  • Angioplasty is a keyhole surgery procedure for repairing damaged or diseased blood vessels. It involves the use of a catheter and a balloon to open up blocked arteries, usually those in the heart. The catheter is passed into a main artery, often in the groin, and pushed along until it reaches the narrowed vessel. The balloon at the tip of the catheter is then inflated so that it pushes opens up the artery – most commonly pushing any build-up of plaque (fatty deposits) in the artery against the vessel's wall – allowing a freer flow of blood. Angioplasty is less radical alternative to open heart or bypass surgery.


    Coronary angioplasty

    Coronary angioplasty is used to restore blood flow through a narrowed or blocked artery in the heart. It is also known by a variety of other names: balloon angioplasty, coronary artery angioplasty, percutaneous coronary intervention, and percutaneous transluminal angioplasty.

    The arteries of the heart – the coronary arteries – can become narrowed and blocked due to buildup of a material called plaque on their inner walls. This narrowing reduces the flow of blood through the artery and can lead, over time, to coronary artery disease and heart attack. In angioplasty, a thin tube called a catheter with a balloon or other device on the end is first threaded through a blood vessel in the arm or groin (upper thigh) up to the site of a narrowing or blockage in a coronary artery. Once in place, the balloon is then inflated to push the plaque outward against the wall of the artery, widening the artery and restoring the flow of blood through it.


    coronary artery with plaque buildup
    Cross-section of a coronary artery with plaque buildup. The coronary artery is located on the surface of the heart. Figure A shows the deflated balloon catheter inserted into the narrowed coronary artery. In figure B, the balloon is inflated, compressing the plaque and restoring the size of the artery. Figure C shows normal blood flow restored in the widened artery.

    Angioplasty is used to:
    • Relieve angina (chest pain) caused by reduced blood flow to the heart.

    • Minimize damage to the heart muscle during a heart attack. This damage occurs when blood flow is totally cut off to an area of the heart.
    Angioplasty was first used in 1977. A tiny balloon was used to open or widen narrowed arteries. Since then, new devices and medicines have improved the procedure and made it appropriate for more people. The improvements include:
    • Stents. A stent is a tiny mesh tube that looks like a small spring. The stent is inserted in the area where the artery is narrowed to keep it open. Some stents are "coated" with medication to help prevent the artery from closing again. Stents are used in most angioplasties except when an artery is too small for a stent to fit.

      • When a stent is used, in 2 out of 10 people the artery will close again within the first 6 months.
      • When a stent is not used, in 4 out of 10 people the artery will close again within the first 6 months.

    • Plaque removers. Many kinds of plaque removers exist. They are used to cut away plaque that narrows the inside of the arteries.


    • Laser. A laser is used to dissolve or vaporize plaque. First approved in 1992, laser devices are used in many major U.S. medical centers.

    placement of stent in coronary artery
    Placement of a stent in a coronary artery with plaque buildup. The coronary artery is located on the surface of the heart. Figure A shows the deflated balloon catheter and closed stent inserted into the narrowed coronary artery. In figure B, the balloon is inflated, expanding the stent and compressing the plaque to restore the size of the artery. Figure C shows normal blood flow restored in the stent-widened artery.

    Today, angioplasty is performed on more than 1 million people a year in the United States. The procedure is best done:
    • By doctors who do at least 75 angioplasties a year
    • In hospitals that do at least 400 angioplasties a year
    Research on angioplasty continues to:
    • Increase its safety
    • Prevent the artery from closing again
    • Make it an option for more people




    When is coronary angioplasty done?

    Your doctor may consider angioplasty if lifestyle changes and medicines do not improve your symptoms of coronary artery disease. Angioplasty is an alternative to coronary bypass surgery, which is a major operation.

    Your doctor will consider several factors when recommending angioplasty or bypass surgery:
    • The number of blocked arteries you have
    • Severity of the blockages
    • Location of the blockages
    • Other medical conditions you have
    • Your surgical risk for bypass
    • Your preference
    Angioplasty is often selected if:
    • The blockage is small.
    • The blockage can be reached by angioplasty.
    • The artery affected is not the main artery that supplies blood to the left side of the heart.
    • You do not have heart failure.
    The advantages of angioplasty are that it:
    • Is not surgery
    • Is done with local anesthesia and mild sedation
    • Has a shorter recovery period than bypass surgery
    • Provides similar survival outcomes as bypass surgery in some patients
    The disadvantage of angioplasty is that the artery may close again. If this happens, you will need a second angioplasty or bypass surgery. Bypass surgery tends to do a more complete job of restoring the heart's blood supply.

    Your doctor will discuss treatment options with you and recommend the best procedure for you.

    Coronary angioplasty is also used as an emergency procedure during a heart attack. Quickly opening a blocked coronary artery minimizes the damage during a heart attack and restores blood flow to the heart muscle. There are also drugs that can be used to dissolve clots in a coronary artery. These drugs are most effective when given within 3 hours after the heart attack begins. Angioplasty performed early, without drugs that dissolve clots, also minimizes damage to the heart muscle.


    What are the risks of coronary angioplasty?

    Angioplasty is a common medical procedure. Major complications are rare, but any medical procedure has risks. The risks of angioplasty include:
    • Bleeding from the blood vessel where the catheter (small flexible tube) was inserted
    • Damage to the blood vessel from the catheter
    • Infection
    • Allergic reaction to dye given during the angioplasty
    Other less-common complications include:
    • Heart attack
    • Need for emergency open-heart surgery during the procedure
    • Stroke
    • Death
    The risk of complications is higher in:
    • Women
    • People ages 75 and older
    • People with diabetes

    What happens before coronary angioplasty?


    Meeting with your doctor

    A heart specialist (cardiologist) performs the angioplasty. If your angioplasty is not done as an emergency, you will meet with your cardiologist before the procedure to have a physical exam and discuss the procedure. Your doctor will order: Your angioplasty will be scheduled at a hospital. You will also be told:
    • When to begin fasting (not eating or drinking) before coming to the hospital
    • What medicines you should and should not take on the day of the angioplasty
    • When to come to the hospital and where to go

    What to expect

    • Angioplasty usually takes 12 hours, depending on the treatment options your doctor uses.
    • During the procedure, you will be awake but sleepy.
    • You will be given medicines to help you relax. These medicines may make you feel sleepy or as though you are floating or numb.
    • A catheter or tube may be left in the blood vessel after the procedure. It is removed 46 hours later. Some doctors use a special device to seal the opening in the blood vessel.
    • You must lie still for several hours until the blood vessel seals.
    • Usually you can return home in 12 days.

    What happens during coronary angioplasty?

    Angioplasty is performed in a special part of the hospital called the cardiac catheterization lab. This lab has special video screens and X-ray machines. Your doctor uses this equipment to see enlarged pictures of the blocked areas in your coronary arteries.


    Preparation (Prep)

    At the cardiac catheterization lab, you will lie on a table. The doctor will use an intravenous (IV) line to give you fluids and medicines. The medicines relax you and prevent blood clots. The rest of your prep includes:
    • Shaving the area where the catheter or tube will be inserted, usually the arm or groin.
    • Cleaning the shaved area to make it germ free.
    • Numbing the area. The numbing medicine may sting as it is going in.

    Steps in angioplasty

    When you are comfortable, the doctor will begin the procedure.
    • A small cut is made in your arm or groin to find an artery. The doctor then threads a very thin wire through the artery up to the area of the coronary artery that is blocked.


    • When the wire reaches the area of the blockage, a tube (catheter) with a deflated balloon on the end is passed over the wire to the site of the blockage.


    • A small amount of dye may be injected through the tube into the blood stream to help show the blockage on X-ray. This X-ray picture of the heart is called an angiogram.


    • When the tube reaches the blockage, the balloon is inflated. The balloon widens the artery to increase the flow of blood to the heart muscle. Plaque removers may be used to take away some of the plaque from the wall of the artery.


    • A stent is usually placed at the site to keep the artery open. The stent remains in place permanently.

    • When the doctor finishes, the wire and catheter are removed. A special outer catheter may remain in place. If a closure device is used, all tubes will be removed.

    During the procedure, strong antiplatelet medicines are given through the IV to prevent clots from forming in the artery or on the stent. These medicines help thin your blood. They usually are started just before the angioplasty and may continue for 1224 hours afterward.


    Recovering

    After the angioplasty procedure, you will be moved to a special care unit.
    • If angioplasty is performed through the artery in your groin, you will have to lie flat without bending your legs. You must lie flat longer if no closure device is used. If the angioplasty is performed through your arm, you will not have to lie flat.

    • If the catheter is removed later, pressure will be applied to the site.
      You must lie still for several hours to allow the blood vessels in your groin (or arm) to seal completely.

    • Afterward, you may walk with assistance.

    While you recover, nurses will check: The place where the tube was inserted may feel sore or tender for about 1 week.

    In most cases, you may go home 12 days after the procedure.


    What happens after coronary angioplasty?

    Angioplasty is not a cure for coronary artery disease (CAD). You should discuss with your doctor what led to CAD and the need for angioplasty.


    Going home

    When you are ready to leave the hospital, you will receive instructions to follow at home, including:
    • How much activity or exercise you can do.
    • When you should follow up with your doctor.
    • What medicines you should take.
    • What you should look for daily when checking for signs of infection around the area where the tube was inserted, such as:
      • Redness
      • Swelling
      • Drainage
    • When you should call your doctor, for example:
      • If you have a fever or signs of infection
      • If you have pain or bleeding where the tube was inserted
    • When you should call emergency service. For example, if you have any chest pain.
    Your doctor will prescribe medicine to prevent blood clots from forming. It is very important that you take the medicine as directed. The medicine can prevent the stent from becoming blocked. Types of medicine may include: Most people can return to work and other normal activities about 1 week after angioplasty.


    Cardiac rehabilitation

    Your doctor may recommend that you participate in a cardiac rehabilitation (rehab) program. Cardiac rehab provides medical guidance and support to help you return to work or daily activities.


    Related categories

       • HEART TOPICS
       • HEALTH AND DISEASE

    Source: U.S. National Heart, Lung and Blood Institute