Cardiac Catheterization

Medically Reviewed By William C. Lloyd III, MD, FACS

What is cardiac catheterization?

Cardiac catheterization is a procedure used to diagnose and treat heart conditions, such as coronary artery disease. Coronary artery disease is a common but serious disease caused by a blockage or narrowing of the arteries that supply blood to the heart. This can lead to a heart attack. 

Doctors perform cardiac catheterization to make detailed images of the heart and perform other tests and treatments. These include heart valve repair and angioplasty to open blocked coronary arteries.

Cardiac catheterization is a minimally invasive procedure that involves passing a long, thin tube (catheter) into your heart by inserting it though a blood vessel in your neck, groin or arm.

Cardiac catheterization is only one method that your doctor can use to diagnose and treat certain heart conditions. Discuss all your options with your doctor to understand which options are right for you. 

Other procedures that may be performed

Cardiac catheterization allows doctors to perform a variety of tests and treatments:

  • Angioplasty to widen a narrowed or obstructed heart artery

  • Blood clot removal, which involves injection of a clot-dissolving medication into the artery via the catheter

  • Coronary angiography, which involves taking real-time X-ray images of your heart and blood vessels. Your doctor sees the images on a video screen as he or she performs your cardiac catheterization. Angiography can detect which coronary arteries are blocked.

  • Heart tissue biopsy, which involves removing a sample of heart muscle cells and testing it for cancer and other diseases

  • Measuring blood pressure in the heart

  • Measuring oxygen levels in the heart

  • Repair of some birth defects of the heart, such as an atrial septal defect. An atrial septal defect is a hole between the upper chambers of the heart.

  • Repair or replacement of diseased heart valves. Heart valve replacement via a catheter is not a standard procedure and is only available at certain medical centers.

  • Stent placement with a mesh tube, which is permanently inserted into the blood vessel to keep the vessel open

  • Taking a blood sample from the heart

Why is cardiac catheterization performed? 

Your doctor may recommend a cardiac catheterization to diagnose and treat certain heart diseases and conditions. The procedure evaluates the function of the heart, heart valves, and the major blood vessels of the heart. This can determine the underlying cause of certain symptoms, such as chest pain

Cardiac catheterization can also help your doctor plan the best treatment for you. Doctors sometimes perform certain treatments right away during the cardiac catheterization. This commonly includes angioplasty to widen narrowed or obstructed heart arteries. Your doctor may also use cardiac catheterization to check your progress after angioplasty or another procedure.

Your doctor may recommend a cardiac catheterization for the following heart diseases and conditions: 

  • Aortic stenosis, a disorder of the valve between your heart and your aorta. Your aorta is the main artery leaving your heart.

  • Blood clots, or coronary thrombosis

  • Chest pain due to abnormal heart function, atherosclerosis (hardening of the arteries), or other conditions
  • Coronary artery disease (CAD), a buildup of plaque on the walls of the coronary arteries that supply blood to the heart

  • Coronary blood vessel malformations present at birth. Many abnormalities do not cause symptoms, but may cause problems at various times from birth through adulthood

  • Heart attack, which is largely due to atherosclerosis or a blood clot blocking blood flow to the heart

  • Heart failure when the underlying cause cannot be determined by other tests

  • Unclear stress test results for symptoms such as shortness of breath or chest pain

  • Unstable angina, which is chest pain that occurs suddenly in the absence of activity. Unstable angina is primarily due to atherosclerosis.

Ask your doctor about all of your treatment options and consider getting a second opinion before deciding on a cardiac catheterization. 

Who performs cardiac catheterization?

Cardiologists and interventional cardiologists often perform cardiac catheterizations. A cardiologist is a doctor who focuses on diagnosing and treating heart diseases. Many cardiologists are trained to perform nonsurgical, catheter-based procedures and specialized imaging techniques (interventional cardiology). 

Other specialists who perform cardiac catheterization include:

  • Cardiac surgeons specialize in the surgical treatment of conditions of the heart and its blood vessels. Cardiac surgeons may also be known as cardiothoracic surgeons.

  • Pediatric cardiologists are internists or pediatricians who have extra training in the medical care conditions and diseases of the heart and its blood vessels.

  • Thoracic surgeons specialize in the surgical treatment of diseases of the chest, including the blood vessels, heart, lungs and esophagus. Thoracic surgeons may also be known as cardiothoracic surgeons.

How is cardiac catheterization performed?

Your cardiac catheterization will be performed in a hospital or outpatient setting. It takes several hours and generally includes these steps:

  1. You will dress in a patient gown and lie on a procedure table.

  2. Your team will insert an IV to provide fluids, medications, or a contrast agent.

  3. Your team attaches devices to monitor your heart rate and blood pressure.|

  4. Your team may give you sedative medications through the IV to help you relax.

  5. Your doctor will determine the location to insert the catheter, often in the groin. The team will shave, clean and numb the area with a local anesthetic. 

  6. Your doctor will make an incision and insert the catheter through the incision. Your doctor will guide the catheter to your heart using special real-time, moving X-rays that he or she sees on a video screen. 

  7. Your doctor will perform an angiography. This involves injection of a contrast agent (dye) through the catheter. The contrast agent improves the image quality. The team then takes X-rays as the contrast agent flows through your heart’s blood vessels. You may feel a brief sensation of warmth during the procedure.

  8. Your doctor may complete other procedures, such as opening a narrowed artery (angioplasty) and placing a stent to keep the artery open.

  9. Your doctor will remove your catheter and sew up the incision.

Will I feel pain?

Your comfort and relaxation is important to you and your care team. You may feel a pinch or pin prick pain during the IV placement and some brief stinging when the catheter site is numbed. You will have enough sedative medications to keep you comfortable. Tell your doctor or care team if you are uncomfortable.

What are the risks and potential complications of cardiac catheterization?  

Cardiac catheterization involves risks and potential complications. Complications may become serious in some cases. Complications can occur during the procedure or recovery. Complications include: 

  • Abnormal heart rhythms (cardiac arrhythmias)

  • Adverse reaction or problems related to sedation or contrast agents, such as an allergic reaction and problems with breathing

  • Bleeding

  • Blood clots that can cause a heart attack, stroke or death

  • Damage to the artery from the catheter

  • Exposure to radiation, which may be harmful in excessive doses. Your care team follows strict standards for X-ray techniques and will use the lowest amount of radiation possible to make the best images.

  • Infection

  • Kidney injury from the contrast agent, especially if you have kidney disease

  • Low blood pressure

  • Need for immediate open heart surgery

Reducing your risk of complications

You can reduce the risk of certain complications by following your treatment plan and: 

  • Following activity, dietary and lifestyle restrictions and recommendations before your procedure and during recovery

  • Informing your doctor if you have kidney disease or diabetes

  • Informing your doctor or radiologist if you are nursing or there is any possibility that you may be pregnant

  • Notifying your doctor immediately of any concerns, such as bleeding, fever, or increase in pain

  • Taking your medications exactly as directed

  • Telling all members of your care team if you have any allergies, especially iodine or shellfish

How do I prepare for my cardiac catheterization?

You are an important member of your own healthcare team. The steps you take before your procedure can improve your comfort and outcome.

You can prepare for cardiac catheterization by:

  • Answering all questions about your medical history and medications you take. This includes prescriptions, over-the-counter drugs, herbal treatments, and vitamins. It is a good idea to carry a current list of your medical conditions, medications, and allergies at all times.

  • Arranging for a ride home after your cardiac catheterization

  • Following instructions about eating and drinking before cardiac catheterization. This generally includes not eating or drinking for six to eight hours before your test. Your doctor will give you specific instructions about eating and drinking.

  • Leaving jewelry, metal objects, credit cards, and other valuables at home

  • Taking or stopping medications exactly as directed. This may include not taking aspirin, ibuprofen (Advil, Motrin), and blood thinners. With certain types of contrast dyes, you should not take metformin (Glucophage), an oral medication for diabetes, for 48 hours before and after your angiography. Your doctor will give you specific instructions about taking your medications.

Questions to ask your doctor

Having a cardiac catheterization can be stressful. It is common for patients to forget some of their concerns during a brief doctor’s office visit. You may also think of other questions after your appointment. Contact your doctor with concerns and questions before your procedure and between appointments.

It is also a good idea to bring a list of questions to your appointment. Common questions include:

  • Why do I need cardiac catheterization? Are there any other options for diagnosing or treating my condition?

  • How long will the procedure take? When can I go home?

  • What restrictions will I have after the procedure? When can I return to work and other activities?

  • What kind of assistance will I need at home? Will I need a ride home?

  • How should I take my medications?

  • How will you treat my pain?

  • When and how will I get the results of my test?

  • What other tests, procedures or surgeries might I need?

  • When should I follow up with you?

  • How should I contact you? Ask for numbers to call during and after regular hours.

What can I expect after my cardiac catheterization?

Knowing what to expect after cardiac catheterization can help you get back to your everyday life as soon as possible.

How will I feel after cardiac catheterization?

You may have mild drowsiness from the sedative medications after the procedure. You may have minor tenderness and bruising at the catheter incision site. You should not feel severe pain. Tell your doctor or care team if you are uncomfortable. Call your doctor after you go home if you have new pain or symptoms, or increasing discomfort at the incision site.

You will need to take it easy for the first couple of days after you go home. You will also need to avoid putting stress on the incision. This includes not straining to have a bowel movement, avoiding heavy lifting, and not participating in strenuous activities. 

You will need to keep the incision clean and dry. Follow your doctor’s instructions for diet, resting, activities, and caring for your incision site.

When can I go home?

You will recover briefly in a recovery room after cardiac catheterization. Your care team will monitor your vital signs and other critical functions for about an hour. They will then transfer you to a hospital room if you need to stay in the hospital. You may need to stay in an intensive care unit (ICU). ICUs provide 24-hour specialized monitoring and care.

Some patients may go home the same day of their cardiac catheterization. In this case, your team will monitor you for four to six hours after the procedure before you go home. You cannot drive for at least 24 hours and you will need a ride home because you may still be drowsy. Someone should stay with you for the first day.

Your doctor will decide if you can go home the same day or if you need to stay in the hospital based on certain factors. These include your general health, medical history, age, and the results of testing performed during your cardiac catheterization.

When should I call my doctor?

It is important to keep your follow-up appointments after cardiac catheterization. Contact your doctor for questions and concerns between appointments. Call your doctor or seek immediate medical care if you have:

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  1. Angiogram. Society for Vascular Surgery.
  2. Angiography. The Department of Radiology and Radiological Sciences of the Uniformed Services University of the Health Sciences.
  3. Angiography or Angiogram. Society of Interventional Radiology.
  4. Angiography Test. Cleveland Clinic.
  5. Catheter Angiography. American College of Radiology.
  6. Coronary Computed Tomography Angiography (CTA). American College of Radiology.
  7. What is Cardiac Catheterization? National Heart Lung and Blood Institute.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Nov 18
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