Cardiologists use a procedure called cardiac catheterization to see how well your heart is working. It can also be used to identify problems and administer a treatment for narrowed or blocked coronary arteries.
Let’s discuss what this procedure entails and how you’ll prepare for and recover from it.
What is a cardiac catheterization?
A cardiac catheterization (sometimes referred to as a “cardiac cath” or a “heart catheterization”) is a procedure that measures the pressure and blood flow in and around the heart. It can also be used to treat certain heart conditions.
During a cardiac catheterization, your doctor may:
- Check the pressure in the four chambers of your heart
- Assess your heart’s chambers as they contract
- Take blood samples to measure the oxygen levels in each chamber
- Look for defects in the valves or chambers of your heart
- Biopsy a small piece of heart tissue
What happens during a cardiac catheterization?
Cardiac catheterizations are performed by a specially-trained doctor and a team of nurses and technicians in a hospital’s cardiac catheterization (cath) lab.
When it’s time for the procedure, a nurse will put an IV line into your arm to administer a sedative. You’ll feel relaxed during the procedure, but you’ll be awake and able to follow instructions. A nurse will also clean and shave the area where the catheter will be inserted (usually the wrist, groin or neck) and use a local anesthetic to numb the area.
Your doctor will insert a small tube called a sheath into a vein or artery. Then, they will gently guide an even smaller tube called a catheter into the blood vessel through the sheath. A video screen will display the catheter’s position as it goes through the major blood vessels to the heart. You may feel pressure, but you shouldn’t experience any pain.
From there, a variety of instruments can be placed at the tip of the catheter. These tools let your doctor:
- Measure the blood pressure in each of the heart’s chambers and in the blood vessels connected to the heart
- View the interior of blood vessels
- Take blood samples from different parts of the heart
- Biopsy a tissue sample from inside your heart
The catheter may also be used to inject contrast dye so that the doctor can create X-rays of your heart’s valves, chambers, and coronary arteries. This test is called an angiography.
In some instances, your doctor might immediately treat a problem after performing these exams. If you have a narrowed or blocked segment of a coronary artery, your doctor may perform an angioplasty to treat it. An angioplasty uses a tiny balloon to push any blockages out of the way and widen your artery to improve blood flow. The doctor may also insert a mesh tube called a stent to help prop the artery open.
At the end of the procedure, the catheter and sheath will be removed, and the site will be covered and dressed to prevent infection.
How do I prepare for a cardiac catheterization?
While a cardiac catheterization usually takes about 30 minutes, the preparation and recovery time add several hours. You should plan on being at the hospital all day, and make sure someone is able to drive you home after the procedure.
You’ll be given instructions about what you can eat and drink during the 24 hours prior to your cardiac catheterization. Typically, you’ll be asked to not eat or drink anything for six to eight hours beforehand.
Your doctor will want to know about any medications you’re taking, including over-the-counter vitamins and supplements. They may ask you to not take them prior to your cardiac catheterization; don’t stop taking them before you’re instructed to do so.
On the day of the procedure, a nurse will ask if you’re allergic to anything, particularly iodine, latex or rubber products, or certain medicines.
If you usually wear a hearing aid, wear it during the procedure. If you wear glasses, bring them with you.
What happens after a cardiac catheterization?
After the procedure, you’ll be moved to a recovery room where you’ll lie flat for a few hours if the catheterization was done via the groin. If the catheter was inserted through your groin, you’ll be asked to keep the closest leg straight. If the catheterization was performed from the wrist or from the neck, you will be observed in the recovery area but can sit up.
Meanwhile, a nurse will monitor your heart rate and blood pressure, as well as any signs of chest pain and swelling, pain, or bleeding at the puncture site.
Before you leave the hospital, you’ll be given written instructions about how to continue your care at home. It’s important that you follow these instructions carefully, including taking any medications that you may be prescribed.
If you have an angioplasty or stent placement in a coronary artery, you will be admitted to the hospital, typically for one night for observation.
A small bruise at the puncture site is normal. If you notice any of the following, call your doctor right away:
- Growth in the bruise size
- Swelling or fluid at the puncture site
- Numbness or tingling in the puncture site
Most people can return to their normal activities the day after the procedure, though you’ll want to avoid strenuous exercise and lifting heavy objects for two weeks. Some additional time may be needed if a treatment was done during your cardiac catheterization. Your doctor will advise you accordingly.
What are the risks of a cardiac catheterization?
Cardiac catheterization is generally a safe procedure. Some people experience minor issues, like bruising around the area where the catheter was inserted. Others may have an allergic reaction to the contrast dye, which can cause nausea.
Other rare potential risks include a perforated blood vessel, blood clots, and an irregular heartbeat.
Prior to the procedure, your doctor will discuss all potential risks with you, as well as any special measures your team will take to prevent them.