Cardiac catheterization (also called cardiac cath or coronary angiogram) is an invasive imaging procedure that tests for heart disease by allowing your doctor to "see" the inside of the arteries and how well your heart is functioning. During the test, a long, narrow tube, called a catheter, is inserted into a blood vessel in your arm or leg and guided to your heart with the aid of a special X-ray machine. Contrast dye is injected through the catheter so that X-ray movies of your valves, coronary arteries, and heart chambers can be created.
Why Do I Need a Cardiac Cath?
Your doctor uses cardiac cath to:
- Evaluate or confirm the presence of heart disease (such as coronary artery disease, heart valve disease, or disease of the aorta)
- Evaluate heart muscle function
- Determine the need for further treatment (such as an interventional procedure or bypass surgery)
At many hospitals, several interventional, or therapeutic, procedures to open blocked arteries are performed after the diagnostic part of the cardiac cath is complete. Interventional procedures include balloon angioplasty and stent placements. Opening an artery that is blocked and preventing blood flow and oxygen delivery to the heart muscle could be a lifesaving procedure.
What Are the Risks of a Cardiac Cath?
Cardiac cath is generally safe. However, as with any invasive procedure, there are risks. Special precautions are taken to decrease these risks. Your doctor will discuss the risks of the procedure with you.
Risks are rare but can include:
- Bleeding around the point of puncture
- Abnormal heart rhythms
- Blood clots
- Allergic reaction to the dye
- Kidney damage from the dye
- Heart attack
- Perforation of a blood vessel
- Air embolism (introduction of air into a blood vessel, which can be life-threatening)
Be sure to ask your doctor any questions you may have before undergoing cardiac cath or other tests for heart disease.
How Should I Prepare for a Cardiac Cath?
You can wear whatever you like to the hospital. You will wear a hospital gown during the procedure.
Leave all valuables at home. If you normally wear dentures, glasses, or a hearing device, plan to wear them during the procedure.
Your doctor or nurse will give you specific instructions about what you can and cannot eat or drink before the procedure.
If you have diabetes, your doctor may recommend holding the metformin and adjusting your insulin the day of your cardiac cath.
Tell your doctor and/or nurses if you are allergic to anything, especially iodine, shellfish, X-ray dye, latex, or rubber products (such as rubber gloves or balloons) or penicillin-type medications.
You may or may not return home the day of your procedure. Bring items with you (such as a robe, slippers, and toothbrush) to make your stay more comfortable. When you are able to return home, arrange for someone to bring you home.
How Long Does Cardiac Catheterization Last?
Cardiac cath usually takes about 30 minutes, but the preparation and recovery time add several hours. Plan on being at the hospital all day for the procedure.
What Happens During a Cardiac Cath?
You will be given a hospital gown to wear during your cardiac cath. A nurse will start an intravenous (IV) line in your arm so that medications and fluids can be administered through your vein during the procedure.
The cardiac catheterization room is cool and dimly lit. You will lie on a special table. If you look above, you will see a large camera and several TV monitors. You can watch the pictures of your cardiac cath on the monitors.
The nurse will clean your skin (and possibly shave) the site where the catheter will be inserted (arm or groin). 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 and not disturb the drapes.
Electrodes (small, flat, sticky patches) will be placed on your chest. The electrodes are attached to an electrocardiogram (ECG) machinethat charts your heart's electrical activity.
A urinary catheter may be necessary for the procedure.
You will be given a mild sedative to help you relax, but you will be awake and conscious during the entire procedure. The doctor will use a local anesthetic to numb the catheter insertion site.
If the catheter is to be inserted into your arm (at the bend of the elbow, called the "brachial" approach, or at the wrist, called the "radial" approach), a local anesthetic will be injected into a vein in your arm to numb the area. A small incision will be made over the blood vessel through which the catheter introducer sheath (a tube through which the catheter is passed) and catheter will be inserted. The catheter will be inserted through the sheath and threaded to the arteries of your heart. Although you may feel pressure as the incision is made or when the sheath and catheter are inserted, you should not feel pain; tell your health care providers if you do.
If the catheter is to be inserted at the groin (called the "femoral" approach), a local anesthetic will be injected to numb the area. A small incision will be made over the blood vessel through which the catheter and introducer sheath will be inserted. The catheter will be inserted through the sheath and threaded to the arteries of your heart. Again, if you feel pain, tell your health care providers.
When the catheter is in place, the lights will be dimmed and a small amount of dye (or 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. This is normal and will go away in a few seconds. Please tell the doctor or nurses if you feel itching or tightness in the throat, nausea, chest discomfort, or any other symptoms.
The X-ray camera will be used to take photographs of the arteries and heart chambers. Your doctor may ask you to take a deep breath, hold your breath, or to cough during the procedure. 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.
What Happens After a Cardiac Cath?
If the catheter was inserted in your arm for your cardiac cath, the catheter and sheath are removed. The incision 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 make sure you are feeling well after the procedure. You may receive medication to relieve discomfort in your arm after the anesthetic wears off. 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 or feel any numbness or tingling in your fingers.
If the catheter was inserted in your groin, the introducer sheath will be removed and the incision will be closed with stitches, a collagen seal, or applied pressure. In some situations, the introducer sheath may be sutured into place and removed later when the risk of bleeding is lower. A collagen seal is a protein material that works with your body's natural healing processes to form a clot in the artery.
A sterile dressing will be placed on the groin area to prevent infection. You will need to lay flat and keep the leg straight for two to six hours to prevent bleeding. Your head can not be raised more than two pillows high (about 30 degrees). Do not raise your head off the pillows, as this can cause strain in your abdomen and groin. Do not try to sit or stand. The nurse will check your bandage regularly, but tell your nurse if you think you are bleeding (have a wet, warm sensation) or if your toes begin to tingle or feel numb. You may receive medication to relieve discomfort in the groin area after the anesthetic wears off. Your nurse will help you out of bed when you are allowed to get up.
Your doctor's orders will determine when you will be allowed out of bed to go to the bathroom after your cardiac cath. You will need assistance getting out of bed, so ask for help. The nurse will help you sit up and dangle your legs on the side of the bed.
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 a urinary catheter was not placed during the procedure, you will need to use a bedpan or urinal until you are able to get out of bed.
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, dietary changes, 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.
Please ask your doctor if you have any questions about cardiac catheterization.