Cardiac is a medical term for the heart. Catheterization means to put a thin, hollow tube (catheter) into some part of your body. So in cardiac catheterization (cardiac cath):
The tube can't go straight into your heart. Doctors get the tube to your heart by putting it in either:
Your arteries are connected to your heart. So the doctor can push the catheter through the artery all the way to your heart.
When the catheter is in your heart, the doctor squirts a special liquid through the catheter. The liquid (called a contrast agent) shows up brightly on x-rays and outlines the inside of your heart. The doctor usually also puts the catheter into each of the arteries that feed your heart (coronary arteries) and squirts the contrast agent into them too. That outlines the inside of those arteries. This test is called coronary angiography.
Most often, doctors do cardiac catheterization to:
Doctors may suspect you have blocked arteries in your heart (coronary artery disease) if:
Less often, you might need cardiac catheterization to see whether you have:
Cardiac catheterization is done in a special unit in the hospital. You can usually go home after the test unless the doctor finds a problem that requires a hospital stay.
The nurses start 1 or 2 IVs and hook you up to machines that monitor your heart and blood pressure
The test is done while you're awake but usually you're given a medicine by vein to help you feel calm
Doctors first inject a medicine to numb the skin over the artery in your arm or groin
When the skin is numb, they make a small cut and insert the catheter
They'll thread the catheter through your major blood vessels and into your heart
Then doctors inject the contrast agent through the catheter
The contrast shows up on x-ray movies that doctors watch on a video screen
The doctor may also use catheters with certain tools on the tip such as:
After catheterization, you'll have a special dressing that applies pressure to your arm or groin to control bleeding.
Sometimes doctors can also treat your heart during cardiac catheterization by:
During angioplasty, the doctor inflates a small balloon on the tip of the catheter. The balloon pushes the blockage open. Often the doctor also slips a wire mesh tube (stent) off the end of the catheter into the blocked area. The wire mesh tube helps hold the blocked area open.
During valvuloplasty, the doctor inflates a larger balloon to push a blocked valve open.
However, some problems found during cardiac catheterization require surgery. Other problems can be treated with medicines.
There are 3 types of side effects from cardiac catheterization. These involve:
The contrast agent makes your body feel very warm when it goes in. Some people feel sick to their stomach. Rarely, you might have serious side effects such as low blood pressure, a bad allergic reaction, or kidney damage.
The catheter in your heart sometimes irritates the heart muscle and causes an abnormal heart rhythm. Rarely the abnormal heart rhythm is dangerous and requires the doctor to give your heart an electric shock (this is called defibrillation).
Usually the hole in your artery hurts only a little and heals quickly. However, sometimes it starts to bleed or heals abnormally. Rarely, the artery becomes blocked so that blood doesn't get through to your arm or leg. Sometimes you will need an operation to fix these problems.
The risk of serious complications depends a lot on:
Overall, your risk of having a serious problem, such as a heart attack or stroke, or of dying from the test is low.