cardiac catheterization

cardiac catheterization

Image credit: Stanford Hospital & Clinics.

Cardiac catheterization is a minimally invasive medical procedure used to diagnose and treat certain heart conditions. A long, thin, flexible tube called a catheter is introduced into a blood vessel in the arm, upper thigh (groin), or neck and threaded up into the heart. Through the catheter, a doctor can perform diagnostic tests and treatments on the heart. Cardiac catheterization is usually performed in a hospital by cardiologists, who specialize in the treatment of heart diseases.


To diagnose some heart conditions, a special dye, known as a contrast medium, may be put into the catheter to make the inside of the heart and blood vessels show up on X-rays. Samples of blood and heart muscle may be taken through the tube. Certain heart problems can be treated during this procedure.


Why is cardiac catheterization done?

Often a cardiac catheterization is performed to find out why a patient is having chest pain. The procedure can reveal blocked or narrowed places in the heart's arteries that can cause this pain. During cardiac catheterization, it may be possible to open up the blocked arteries by doing another procedure called angioplasty.


Most people who have heart attacks have arteries that are partly or completely blocked. That is why cardiac catheterizations are often carried out after patients have heart attacks. The procedure can indicate if there are blocked arteries that can be treated with angioplasty or surgery.


Another reason for doing cardiac catheterizations is to look at the overall shape of the heart and its four chambers (the atria and ventricles). This makes it possible to:


  • Find any likely problems in people about to have open heart surgery
  • See heart abnormalities in children or adults

    Sometimes cardiac catheterization is performed to see how well the valves (flaps of tissue) at the openings and exits of the heart chambers are working. To do this, measurements are made of the blood flow and oxygen levels in different parts of the heart. Cardiac catheterization is also done to check the functioning of artificial heart valves and to carry out minor surgical procedures on the heart. These minor procedures may include the removal (biopsy) of a small piece of heart tissue to see if there is an infection or tumor, or the repair of holes in the heart or other heart defects.


    Cardiac catheterization is a common medical procedure that rarely causes serious problems. But complications can include:


  • Bleeding, infection, and pain where the tube (catheter) was inserted
  • Damage to blood vessels
  • An allergic reaction to the dye used

    Other less common complications of the procedure include:


  • An irregular heartbeat.
  • Damage to the kidneys caused by the dye used.
  • Blood clots that can trigger strokes, heart attacks, or other serious problems.
  • Hypotension (low blood pressure).
  • A buildup of blood or fluid in the sac that surrounds the heart. This fluid can prevent the heart from beating properly.

    As with any procedure involving the heart, complications can sometimes, although rarely, be fatal.


    The risk of complications with cardiac catheterization is higher in:


  • People with diabetes
  • People with kidney disease
  • Older people (ages 75 and older)
  • Women
  • People having emergency catheterization for serious heart symptoms

    Preparing for a cardiac catheterization

    Before having a cardiac catheterization, it is a good idea for the patient to meet with his/her doctor to learn about the procedure and how to prepare for it. In that meeting, the patient might discuss things such as:


  • Any medicines he/she is taking, and whether he/she should stop taking some of these drugs before the procedure

  • Whether he/she has diabetes, kidney disease, or other conditions that may require taking extra steps during or after the procedure to avoid complications

    Patients are not usually allowed to drive the same day they have a cardiac catheterization. If they don't have to stay overnight after this procedure, they should arrange for a ride to and from the hospital.


    During a cardiac catheterization

    During a cardiac catheterization, the patient is kept on his/her back and awake. That way the patient can follow instructions given during the procedure. A drug is administered to aid relaxation, which make make the patient sleepy.


    A doctor or nurse will numb the area where the small plastic tube (catheter) will enter the blood vessel through a small cut or needle in the arm, upper thigh (groin), or neck. The catheter is then threaded through the vessel and into the chambers of the heart. Special X-ray movies are taken of the tube as it is threaded up into the heart. This helps the doctor see where to put the tube.


    Once the catheter is at the right spot, it can be used it to conduct several tests or treatments. Often, special dye is put in the tube to make the inside of the heart's arteries and other structures show up on an X-ray. A procedure called angioplasty may be used to open up the blocked arteries and blood samples may be taken from different parts of the heart or do minor heart surgery.


    Once the doctor does all of the needed tests or treatments, the catheter will be taken out. The opening in the blood vessel that the tube went through will then be closed up and bandaged. A small sandbag or other type of weight may be put on top of the bandage to apply more pressure. This will help prevent major bleeding from the site.


    After a cardiac catheterization

    After a cardiac catheterization, the patient will be moved to a special care area where you will stay for several hours or overnight. While recovering in this area, the patient's movement is limited to avoid bleeding from where the tube (catheter) was inserted. Nurses will check your heart rate and blood pressure regularly. They will also check to see if there is any bleeding from the tube insertion site.


    Eventually, a small bruise will appear where the tube was put in. That area may feel sore or tender for about a week. The patient should let his/her doctor know if:


  • There is a constant or large amount of blood at the site that can't be stopped with a small bandage.
  • There is any unusual pain, swelling, redness, or other signs of infection at or near the insertion site.

    The patient may be asked to avoid certain activities, such as heavy lifting, for a short time after the procedure.