Who Needs Cardiac Catheterization?
Cardiac catheterization is used to diagnose and/or treat many heart conditions. Doctors may recommend this procedure for various reasons. The most common reason is to evaluate chest pain.
Chest pain may be a symptom of coronary artery disease (CAD). Cardiac catheterization can show whether plaque is narrowing or blocking your heart's arteries.
Doctors can treat CAD during cardiac catheterization with a procedure called angioplasty. During angioplasty, a tiny balloon is put through the catheter and into the blocked artery. When the balloon is inflated, it pushes the plaque against the artery wall. This creates a wider pathway for blood to flow to the heart.
Sometimes a stent is placed in the artery during angioplasty. A stent is a small mesh tube that's used to treat narrowed or weakened arteries in the body.
Most people who have heart attacks have partly or completely blocked coronary arteries. Thus, cardiac catheterization may be done on an emergency basis while you're having a heart attack. When used with angioplasty, the procedure allows your doctor to open up blocked arteries and prevent more damage to your heart.
Cardiac catheterization also can help your doctor figure out the best treatment for your CAD if you:
- Recently recovered from a heart attack, but are having chest pain
- Had a heart attack that caused major damage to your heart
- Had an EKG (electrocardiogram), stress test, or other test with results that suggested heart disease
You also may need cardiac catheterization if your doctor suspects you have a heart defect or if you're about to have heart surgery. The procedure shows the overall shape of your heart and the four large spaces (heart chambers) inside it. This inside view of the heart will show certain heart defects and help your doctor plan your heart surgery.
Sometimes doctors do cardiac catheterization to see how well the valves at the openings and exits of the heart chambers are working. Valves control the flow of blood in the heart.
To check your valves, your doctor will measure blood flow and oxygen levels in different parts of your heart. Cardiac catheterization also can check how well a man-made heart valve is working and how well your heart is pumping blood.
If your doctor thinks you have a heart infection or tumor, he or she may take samples of your heart muscle through the catheter. With the help of cardiac catheterization, doctors can even do minor heart surgery, such as repair certain heart defects.
What To Expect During Cardiac Catheterization
Cardiac catheterization is done in a hospital. During the procedure, you'll be kept on your back and awake. This allows you to follow your doctor's instructions during the procedure. You'll be given medicine to help you relax, which may make you sleepy.
Your doctor will numb the area on the arm, groin (upper thigh), or neck where the catheter will enter your blood vessel. A needle is used to make a small hole in the blood vessel. Through this hole your doctor will put a tapered tube called a sheath.
Next, your doctor will put a thin, flexible wire through the sheath and into your blood vessel. This guide wire is then threaded through your blood vessel to your heart. The wire helps your doctor position the catheter correctly. Your doctor then puts a catheter through the sheath and slides it over the guide wire and into the coronary arteries.
Special x-ray movies are taken of the guide wire and the catheter as they're moved into the heart. The movies help your doctor see where to position the tip of the catheter.
When the catheter reaches the right spot, your doctor will use it to do tests or treatments on your heart. For example, your doctor may do angioplasty and stenting. During the procedure, your doctor may put a special dye in the catheter. This dye will flow through your bloodstream to your heart. Once the dye reaches your heart, it will make the inside of your heart's arteries show up on an x ray called an angiogram. This test is called coronary angiography.
Coronary angiography can show how well blood is being pumped out of the heart's main pumping chambers, which are called ventricles. When the catheter is inside your heart, your doctor may use it to take blood samples from different parts of the heart or to do minor heart surgery.
To get a more detailed view of a blocked coronary artery, your doctor may do intracoronary ultrasound. For this test, your doctor will thread a tiny ultrasound device through the catheter and into the artery. This device gives off sound waves that bounce off the artery wall (and its blockage) to make an image of the inside of the artery.
If the angiogram or intracoronary ultrasound shows blockages or other possible problems in the heart's arteries, your doctor may use angioplasty to open the blocked arteries.
After your doctor does all of the needed tests or treatments, he or she will pull back the catheter and take it out along with the sheath. The opening left in the blood vessel will then be closed up and bandaged. A small weight may be put on top of the bandage for a few hours to apply more pressure. This will help prevent major bleeding from the site.