During the Procedure

During the Procedure

What to expect during a cardiac catheterization


  • Please bring a list of your medications (including over-the-counter) and dosages. When you arrive for your appointment, please tell your nurse if you are taking Coumadin (warfarin), Plavix (clopidogrel), diuretics (water pill) or insulin. Also remind the staff if you are allergic to anything, especially iodine, shellfish, x-ray dye, penicillin-type medications, latex or rubber products (such as rubber gloves or balloons).
  • You will be given a hospital gown to wear.
  • A nurse will start an intravenous (IV) line in your arm so that medications and fluids can be administered during the procedure.
  • The cardiac catheterization room is cool and dimly lit. The air must be kept cool to prevent damage to the x-ray machinery that is used during the procedure. You will be offered warm blankets to make you more comfortable.
  • You will lie on a special table. If you look above, you will see a large camera and several TV monitors. You can watch your cardiac cath on the monitors.
  • The nurse will clean your skin at the site where the catheter (narrow plastic tube) will be inserted (arm or groin). The catheter insertion site may be shaved.
  • Sterile drapes are used to cover the site and help prevent infection. It is important that you keep your arms and hands down at your sides, under the sterile drapes.
  • Electrodes (small, flat, sticky patches) will be placed on your chest. The electrodes are attached to an electrocardiograph monitor (ECG), which monitors your heart rate and rhythm.
  • You will be given a mild sedative to relax you, but you will be awake and conscious during the entire procedure.
  • In some cases, a urinary catheter may be needed during the procedure.
  • The doctor will use a local anesthetic to numb the site. A plastic introducer sheath (a short, hollow tube through which the catheter is placed) is inserted in a blood vessel in your arm or groin. A catheter will be inserted through the sheath and threaded to the arteries of your heart. You may feel pressure as the introducer sheath or catheter are inserted, but you should not feel pain. Tell the nurse or doctor if you feel any pain.
  • When the catheter is in place, the lights will be dimmed and a small amount of contrast material will be injected through the catheters into your arteries and heart chambers. The contrast material outlines the vessels, valves and chambers.
  • When the contrast material is injected into your heart, you may feel hot or flushed for several seconds. This is normal and will go away in a few seconds.

Please tell the doctor or nurses if you feel:


  • an allergic reaction (itching, tightness in the throat, shortness of breath)
  • nausea
  • chest discomfort
  • any other symptoms
  • The x-ray camera will be used to take photographs of the arteries and heart chambers. You will be asked to hold your breath while the x-rays are taken. When all the photos have been taken, the catheter will be removed and the lights will be turned on.
  • You may have an interventional procedure combined with your cardiac catheterization. Learn more about interventional procedures
  • The catheters and sheath are removed.
    • If the catheter was inserted in the arm: The puncture site will be bandaged. You will need to keep your arm straight for at least an hour. You will be able to walk around. You will be observed for a few hours to monitor any symptoms or side effects of the procedure. You will be given instructions regarding how to care for your arm when you return home. Tell your nurse if you think you are bleeding (wet, warm sensation) or feel any numbness or tingling in your fingers.
    • If the catheter was inserted at the groin: The puncture site will be closed with applied pressure, suture device or a “plug.” A “plug” is a material which works with your body’s natural healing processes to form a clot in the artery. You will need to lie flat and keep the leg straight for two to six hours to prevent bleeding (less time if a plug was used). Your head cannot be raised more than 30 degrees (two pillows high). Do not try to sit or stand. A sterile dressing will be placed on the groin area to protect it from infection. The nurse will check your bandage regularly, but call your nurse if you think you are bleeding (have a wet, warm sensation) or if your toes begin to tingle or feel numb.
  • You will need to drink plenty of liquids to clear the contrast material from your body. You may feel the need to urinate more frequently. This is normal. If you are on bed rest, you will need to use a bedpan or urinal.
  • Your doctor will tell you if you are able to return home or will need to stay overnight. In either case, you will be monitored for several hours after the procedure.
  • Treatment, including medications, diet and future procedures, will be discussed with you prior to going home. Care of the wound site, activity and follow-up care will also be discussed.