Cardiac catheterization (kath-uh-tur-ih-ZAY-shun) is a procedure used to diagnose and treat certain cardiovascular conditions. During cardiac catheterization, a long thin tube called a catheter is inserted in an artery or vein in your groin, neck or arm and threaded through your blood vessels to your heart.

Using this catheter, doctors can then do diagnostic tests as part of a cardiac catheterization. Some heart disease treatments, such as coronary angioplasty and coronary stenting, also are done using cardiac catheterization.

Usually, you’ll be awake during cardiac catheterization but be given medications to help you relax. Recovery time for a cardiac catheterization is quick, and there’s a low risk of complications.

Why it’s done

Cardiac catheterization is done to see if you have a heart problem. It can also be done as part of a procedure to correct a known heart problem.

If you’re having cardiac catheterization as a test for heart disease, your doctor can:

• Locate narrowing or blockages in your blood vessels that could cause chest pain (angiogram)
• Measure pressure and oxygen levels in different parts of your heart (hemodynamic assessment)
• Check the pumping function of your heart (right or left ventriculogram)
• Take a sample of tissue from your heart (biopsy)
• Diagnose heart defects present from birth (congenital heart defects)
• Look for problems with your heart valves

Cardiac catheterization is also used as part of some procedures to treat heart disease. These procedures include:

• Widening a narrowed artery (angioplasty) with or without stent placement
• Closing holes in the heart and fixing other congenital defects
• Repairing or replacing heart valves
• Opening narrow heart valves (balloon valvuloplasty)
• Treating irregular heart rhythms with ablation
• Closing off part of your heart to prevent blood clots

Risks

As with most procedures done on your heart and blood vessels, cardiac catheterization has some risks. Major complications are rare, though.

Risks of cardiac catheterization are:

• Bruising
• Bleeding
• Heart attack
• Stroke
• Damage to the artery, heart or the area where the catheter was inserted
• Irregular heart rhythms (arrhythmias)
• Allergic reactions to the dye or medication
• Kidney damage
• Infection
• Blood clots

If you are pregnant or planning to become pregnant, tell your doctor before having the procedure.

How you prepare

Cardiac catheterization is usually performed in the hospital. The test requires some preparations. Before your test:

• Don’t eat or drink anything for at least 6 hours before your test, or as directed by your doctor.Having food or drink in your stomach can increase your risk of complications from anesthesia. Ask your doctor or nurse if you should take your medications with a small amount of water.

If you have diabetes, ask for instructions about diabetes medications and insulin. You will usually be able to have something to eat and drink soon after your test.

• Your doctor may recommend you stop medications that may thin your blood,such as warfarin, aspirin, apixaban, dabigatran and rivaroxaban.
• Take all your medications and supplements with you to the test.It’s best if you take the original bottles so that your doctor will know the exact dose you take.

What you can expect

Before the procedure

You’ll have your blood pressure and pulse checked. You’ll also be asked to use the toilet to empty your bladder.

You’ll need to remove dentures and may need to remove jewelry, especially necklaces that could interfere with pictures of your heart. You’ll wait in a preop room until it’s time for your procedure — you can often have someone wait there with you.

During the procedure

Cardiac catheterization is done in a procedure room with special X-ray and imaging machines. Like an operating room, the cardiac catheterization lab is a sterile area.

Cardiac catheterization is usually performed while you’re awake but sedated. However, certain procedures, such as ablation, valve repair or valve replacement, may be performed while you’re under general anesthesia.

An IV line will be inserted in your hand or arm and will be used to give you any additional medications you might need during your procedure. You will also have monitors (electrodes) placed on your chest to check your heartbeat during the test.

Just before the procedure, a nurse or technician may shave the hair from the site where the catheter will be inserted. Before the catheter is inserted in your artery, you’ll be given a shot of an anesthetic to numb the area. You may feel a quick, stinging pain before the numbness sets in.

After you feel numb, the catheter will be inserted. A small cut is made to access an artery. A plastic sheath will be inserted in the cut to allow your doctor to insert the catheter.

What happens next depends on why you’re having a cardiac catheterization. These are some of the common uses for cardiac catheterization:

• Coronary angiogram.If you’re having this test to check for blockages in the arteries leading to your heart, a dye will be injected through the catheter, and X-ray images of your heart arteries will be taken. In a coronary angiogram, the catheter is usually first placed in the artery in your groin or wrist.
• Right heart catheterization.This procedure checks the pressure and blood flow in the right side of your heart. A catheter is inserted in the vein in your neck or groin. The catheter has special sensors in it to measure the pressure and blood flow in your heart.
• Heart biopsy.If your doctor is taking a sample of heart tissue (biopsy), the catheter will usually be placed in the vein in your neck. Less often, it may be placed in your groin. A catheter with a small, jaw-like tip is used to obtain a small sample of tissue from your heart.

You may feel pressure as this catheter is being used, but you likely won’t feel the actual tissue being snipped.

• Balloon angioplasty, with or without stenting.This procedure is used to open a narrowed artery in or near your heart. The catheter can be inserted in either your wrist or groin for this procedure.

A long, flexible catheter will be threaded through your arteries to the narrowed artery. Then, a smaller balloon catheter will be fed through the flexible catheter and inflated at the narrowed area to open it. In many cases, your doctor will also place a mesh coil called a stent at the narrowed portion to help keep the artery open.

• Repair of heart defects.If your doctor is closing a hole in your heart, such as an atrial septal defect or patent foramen ovale, you will probably have catheters inserted in both the arteries and veins of the groin and neck. A device is then inserted into your heart to close the hole. In cases of heart valve leak repair, a clip or plug may be used to stop the leak.
• Balloon valvuloplasty.This procedure is done to open up narrowed heart valves. The placement of your catheters will depend on which valve problem you have.

A catheter is threaded across the valve. A balloon is then blown up to make the valve open more easily. You may feel pressure as the catheters are inserted into your body, but you shouldn’t feel discomfort from the balloon treatment itself.

• Valve replacement.This procedure is similar to balloon valvuloplasty, except that an artificial valve will be implanted in your heart to replace a narrowed heart valve.
• Heart ablation.In this procedure, you’ll usually have multiple catheters placed in the arteries and veins of your groin or neck so that radiofrequency energy can be directed to the part of your heart causing abnormal heartbeats.

If you’re awake during the procedure, you may be asked to take deep breaths, hold your breath, cough or place your arms in various positions throughout the procedure. Your table may be tilted at times, but you’ll have a safety strap on to keep you on the table.

Threading the catheter shouldn’t be painful, and you won’t feel it moving through your body. Tell your health care team if you have any discomfort.

After the procedure

You’ll likely spend several hours in a recovery room after the procedure while the anesthesia wears off. The plastic sheath inserted in your groin, neck or arm is usually removed soon after the procedure.

After you leave the recovery room, you’ll go to a regular hospital or outpatient room. After your catheter is removed, the technician or nurse who has removed your sheath will apply pressure to the insertion sites. If the groin is used, you’ll need to lie flat for several hours after the procedure to avoid serious bleeding and to allow the artery to heal.

You’ll be able to eat and drink after the procedure. The length of your stay in the hospital will depend on your condition. You may be able to go home the same day as your catheterization, or you may need to stay overnight or longer if you have an additional procedure, such as angioplasty and stent placement.

Results

If you’re having cardiac catheterization as a test, your doctor should explain the results to you.

If you’ve had a coronary angiogram, your results could mean that you need angioplasty or a stent. If your doctor finds this, he or she may perform angioplasty with or without a stent placement right away so that you won’t need to have another cardiac catheterization. Your doctor should discuss whether this is a possibility before the procedure begins.

It’s also possible that the test may show you need an open-heart surgery called coronary bypass surgery.