Heart Catheterization

What is heart catheterization?

Heart catheterization is a test done to look at the heart in detail. Your healthcare provider will put a very thin flexible tube called a catheter into a blood vessel in your arm, leg, or neck. The catheter will then be guided up to the heart.

Heart catheterization can:

• Allow X-ray pictures (angiograms) outlining the heart chambers or coronary arteries to be taken with use of a special dye.
• Record the blood pressure in the blood vessels in the lungs and the heart. It can also measure blood pressure in the chambers of the heart.
• Measure blood flow and oxygen content of blood in different parts of the heart.
• Show how well the heart is pumping blood to the body.
• Take a tissue sample (biopsy) of the heart muscle using a tool passed through the catheter.

Another name for this test is also called cardiac catheterization.

When is it used?

Some of the reasons heart catheterization may be done are:

• Coronary artery disease: If your coronary arteries are partly or completely blocked, you have an increased risk of a heart attack, especially if your symptoms have gotten worse recently. Cardiac catheterization and the injection of dye into the arteries is the best way to study the coronary arteries. The dye study shows the location and the amount of the blockage. This test may be done to see if you need coronary bypass surgery or coronary angioplasty.
• Open-heart surgery: Sometimes catheterization is needed before open-heart surgery. The surgeon needs to check for any conditions that may increase the risk of problems during surgery.
• Heart valve disease: If you may need heart valve surgery, you may have a heart catheterization so your healthcare provider can see how the valves and the rest of the heart are working.
• Birth defects of the heart: A child born with a heart problem may need to have catheterization in early childhood. It helps the surgeon see the structure of the child's heart and where there are defects.
• Biopsy: During the test a piece of heart muscle can be removed and checked for inflammation or other problems.
• Angioplasty: Catheters can be used to open a narrowed heart valve or artery. Balloon angioplasty, for example, uses pressure from a balloon at the tip of the catheter to help open a narrowed artery.
• Stenting: Catheters may also be used to remove plaque buildup and to place stents that hold open arterial walls.

How do I prepare for the test?

Before the test, your healthcare provider will want to know what medicines you are taking. If you are taking daily aspirin for a medical condition, ask your provider if you need to stop taking it before your test.

Talk with your healthcare provider about what medicines you should take before the test. Your provider may prescribe medicine to prevent blood clots from forming during the test.

Tell your provider if you have had any kidney problems or reactions to iodine-containing foods, such as seafood, or chemicals, such as X-ray contrast dye.

Follow the instructions your healthcare provider gives you. Eat a light meal the night before the test. You may be asked not to eat or drink anything for 12 hours before the test. If you have diabetes, your provider may give you special instructions about your diabetic medicine.

Arrange for someone to drive you home after the test.

What happens during the test?

This test is usually done at the hospital.

Before the test you will be given medicine to help you relax, but you will be awake during the test. You will also be given a shot of anesthetic to numb the area where the catheter will be inserted.

Your healthcare provider will put the catheter through your skin and into a blood vessel in your groin, arm, or neck. The catheter will be passed through blood vessels toward the heart. X-rays are used to follow the position of the catheter. You will not feel the catheter as it passes through your blood vessels.

Your provider will guide the tip of the catheter to precise positions in the heart and its blood vessels. The catheter is attached to a device that measures blood flow and blood pressure in different places in the heart and blood vessels.

If pictures of the heart chambers, valves, or coronary arteries are needed, a special kind of liquid (called contrast or dye) is injected through the catheter. X-rays are taken while the dye moves through your artery. Sometimes the X-rays are taken so fast that they make a movie that shows how the dye is moving through the artery. This test with dye is called an angiogram.

At the end of the test, your healthcare provider will remove the catheter and put pressure on the area where the catheter was inserted (the puncture site) to control any bleeding.

The test takes about an hour.

What happens after the test?

After the test you may stay in an observation area for at least a few hours to make sure the puncture site is not bleeding. Usually you do not need to stay in the hospital overnight for this test.

Avoid any strenuous activity for the rest of the day to prevent bleeding. You may have a bruise near the puncture site and be uncomfortable for a few days.

Ask your healthcare provider how to take care of yourself at home. Ask about what symptoms to watch for, and what precautions you should take. Ask how and when you should expect to hear your test results. Make sure you know when you should come back for a checkup.

What are the benefits of this test?

Heart catheterization is considered the most accurate way to get the information your healthcare provider needs to diagnose and treat heart problems. Your provider will study the X-ray moving pictures to see if your heart valves are normal, to check how well the heart is pumping, and to look for possible blockages in the coronary arteries. He or she will note the direction and amount of blood flow through the heart. Treatment based on this information can help prevent heart failure and heart attacks.

What are the risks of this test?

Complications from this test are rare. Possible risks include:

• You may have an allergic reaction to the dye. An allergic reaction may cause hives, trouble breathing, a drop in blood pressure, unconsciousness, or swelling of the skin. This reaction can be treated with medicine.
• The dye could damage the kidneys. If you have diabetes or kidney disease, you may have a higher risk for kidney damage. Your healthcare provider may want you to take medicine before and after the test to help protect your kidneys.
• The test can cause irregular heart rhythms, which could need treatment.
• You may have bleeding where the catheter was put into your blood vessel.
• If the catheter is placed in an artery, a blood clot could form around the catheter. A clot could block the artery.
• The catheter may damage an artery, for example, the blood vessel in the groin or arm where the catheter was inserted.
• In rare cases, you may have an allergic reaction to the drug used in the anesthesia.
• While not common, a heart attack or stroke might be triggered by the test.

You should ask your healthcare provider how these risks might apply to you.

When should I call my healthcare provider?

Call your provider right away if:

• The place where the catheter was put into your skin starts to bleed or swell, or it gets more painful.
• You have a fever.
• Your leg or foot is painful or unusually cool.
• You have slurred speech, balance problems, or trouble using your arm or leg.
• You start having a rash, itching, sweating, or trouble breathing.
• You have chest pain that is new or different from chest pain you have had before.

Call during office hours if:

• You have questions about the test or its result.
• You want to make another appointment.