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:
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.
Risks
Cardiac catheterization is a common medical procedure that rarely causes serious problems. But complications can include:
Other less common complications of the procedure include:
As with any procedure involving the heart, complications can sometimes, although rarely, be fatal.
The risk of complications with cardiac catheterization is higher in:
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:
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:
The patient may be asked to avoid certain activities, such as heavy lifting, for a short time after the procedure.