Cardiac Catheterization

What is cardiac catheterization?

Cardiac catheterization (cardiac cath or heart cath) is a procedure to examine how well your heart is working. It is used to diagnose some heart problems. It is one of the most common heart procedures performed in the U.S. View an illustration of cardiac catheterization(link opens in new window).

cardiac catheter

Why do people have cardiac catheterization?

A cardiac cath provides information on how well your heart works, identifies problems and allows for procedures, such as angioplasty and stenting, to open blocked arteries. During a cardiac cath your health care team may:

  • Take X-rays using contrast dye injected through the catheter to look for narrowed or blocked coronary arteries. This is called coronary angiography or coronary arteriography.
  • Perform a percutaneous coronary intervention (PCI) such as coronary angioplasty with stenting to open up narrowed or blocked segments of a coronary artery.
  • Check the pressure in the four chambers of your heart.
  • Take samples of blood to measure the oxygen content in the four chambers of your heart.
  • Evaluate the ability of the pumping chambers to contract.
  • Look for defects in the valves or chambers of your heart.
  • Remove a small piece of heart tissue (biopsy) to examine under a microscope.

angiogram illustration

Watch an animation of an angiogram

What are the risks of cardiac catheterization?

Cardiac cath is usually very safe. Major complications are very rare. Some minor risks include:

  • Bruises where the catheter had been inserted (puncture site).
  • Bleeding at the puncture site.
  • Reaction to the contrast dye.
  • Infection.
  • Side effects from the medicines to help you relax or sleep, such as nausea or vomiting.

Some other risks include:

  • Abnormal heart rhythm
  • Blood clots
  • Damage to a blood vessel or heart from the catheter
  • Heart attack
  • Side effects from X-rays
  • Stroke  

How do I prepare for cardiac catheterization?

  • You will be given instructions about what to eat and drink 24 hours prior to the test.
  • You usually will be asked not to eat or drink anything for six to eight hours before the procedure.
  • Tell your health care team immediately if you think you might be pregnant.
  • Tell your health care team about any medicines (including over-the-counter, herbs and vitamins) you take. They may ask you not to take them before your procedure.
  • Tell your health care team if you are allergic to anything, especially iodine, shellfish, latex or rubber products, X-ray dye or medicines such as penicillin.
  • Arrange to have someone drive you home after your procedure.
  • If you have a hearing aid, you can wear it during your procedure. If you wear glasses, bring them to your appointment.

What happens during cardiac catheterization?

A doctor with special training performs the procedure with a team of nurses and technicians. The procedure is done in a cardiac catheterization (cath) lab at a hospital or medical clinic.

  • Before the cath procedure, a nurse will put an IV (intravenous) line into a vein in your arm so you can get medicine (sedative) to help you relax, but you’ll be awake and able to follow instructions during the procedure.
  • The nurse will clean and shave the area where the doctor will be working. This is usually in the groin area.
  • A local anesthetic is usually given to numb the puncture site.
  • The doctor will make a needle puncture through your skin and into a large blood vessel. A small straw-sized tube (called a sheath) will be inserted into the vessel. The doctor will gently guide a catheter (a long, thin tube) into your vessel through the sheath. A video screen will show the position of the catheter as it is threaded through the major blood vessels and to the heart. You may feel some pressure in your groin, but you shouldn’t feel any pain.
  • Various instruments may be placed at the tip of the catheter. They include instruments to measure the pressure of blood in each heart chamber and in blood vessels connected to the heart, view the interior of blood vessels, take blood samples from different parts of the heart, or remove a tissue sample from inside the heart.
  • When a catheter is used to inject a dye that can be seen on X-rays, the procedure is called angiography.
  • When a catheter is used to clear a narrowed or blocked artery, the procedure is called angioplasty or a percutaneous coronary intervention.
  • When a catheter is used to widen a narrowed heart valve opening, the procedure is called valvuloplasty.
  • The doctor will remove the catheters and the sheath. Your nurse will put pressure on the site to prevent bleeding. Sometimes a special closure device is used.

What happens after cardiac catheterization?

You will go to a recovery room for a few hours. During this time, you must lie flat.

  • Pressure will be applied to the puncture site to stop any bleeding.
  • You will be asked to keep your leg straight and will not be able to get out of bed.
  • Your heartbeat and other vital signs (pulse and blood pressure) will be checked during your recovery. 
  • Report any swelling, pain or bleeding at the puncture site, or if you have chest pain.
  • If you had an additional procedure during the cardiac cath, you may have to spend the night in the hospital.
  • Before you leave the hospital, you will receive written instructions about what to do at home.

What happens after I get home?

Be sure to follow all instructions provided by your health care team. It is important to take your medications as directed and to make follow-up appointments before leaving the hospital. Most people can return to their normal activities the day after the procedure depending on whether any additional procedures were done during the cardiac cath.

A small bruise at the puncture site is normal. If the site starts to bleed, lie flat and press firmly on top of it for a few minutes. Then, recheck to see if the bleeding has stopped. 

Call your health care professional if:

  • Your leg with the puncture becomes numb or tingles, or your foot feels cold or turns blue.
  • The area around the puncture site looks more bruised.
  • The puncture site swells or fluids drain from it.
  • Bleeding from the access site can’t be stopped with firm pressure.
  • You experience:
    • Chest pain or shortness of breath
    • Dizziness
    • Fever
    • Irregular, very slow or fast heartbeat

Call 911 if:

  • The puncture site swells up very fast.
  • Bleeding from the puncture site does not slow down when you press on it firmly.

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