A coronary angiogram can help your cardiologist look for blockages in your coronary arteries. X-ray images from your procedure will help your provider make a diagnosis and decide if you need medicine, a stent or surgery. Plan on spending a few hours at the hospital for the procedure and recovery.
A coronary angiogram is a test that uses X-rays to show how well your blood is moving in your heart’s arteries (coronary arteries), and to look for clogs in them. Your coronary arteries are important because they get blood to your heart’s muscle. A blocked coronary artery can lead to a heart attack, which is when heart muscle dies.
Your provider may do coronary angiography when deciding if you need:
You may need a coronary angiogram when:
A healthcare provider who’s a heart expert ― a cardiologist ― will perform your coronary angiogram.
Contrast dye that’s injected into your coronary arteries through a small catheter allows your provider to see (through X-ray images) if there is blockage of your coronary arteries. The most common cause of narrowing of the coronary arteries is cholesterol plaque (atherosclerosis).
Your provider will most likely tell you not to eat or drink anything for eight hours before your coronary angiogram procedure. If your provider tells you to do so, you may need to avoid these medicines for at least one day before your procedure:
You’ll lie on your back for the procedure. Your healthcare provider will give you medicine that makes you feel relaxed, but you’ll still be awake enough to follow their instructions. An electrocardiogram (EKG) will monitor your heart rhythm during your procedure.
They’ll use medicine to keep you from feeling pain at the place on your groin or arm where your provider accesses your artery. You may feel pressure, but should not feel pain. Your cardiologist will place a sheath (or tube) in your artery. This tube serves as a small port through which they will pass wires and catheters to find your coronary arteries on the surface of your heart. An X-ray machine will rotate around you (called fluoroscopy), which will allow your provider to see where the catheter is going from all angles. You won’t feel the tube going through your blood vessels.
After your provider gets the catheter into your heart or aorta, they’ll put dye into the tube and look at X-rays to watch the dye go through your artery. You might feel warm when the dye goes into your body. Rarely, your chest may feel uncomfortable as the dye is going into it.
Your provider will be able to see if anything (like cholesterol or plaque) is getting in the way of blood going through your coronary arteries. If they see something blocking your blood flow, they may be able to clear the blockage with a balloon (a procedure called angioplasty), and then place a stent (a metal scaffold usually coated with a drug), to keep your artery open. Angioplasty and stenting are types of percutaneous coronary intervention (or PCI). This can be performed right then, or staged for a later time.
Occasionally, your provider will recommend coronary artery bypass grafting (CABG). If this is the case, they won’t do PCI. Instead, they’ll stop the procedure and consult a surgeon. The timing of surgery will depend on the person and situation. Your provider could arrange this before you go home or electively on an outpatient basis.
When your coronary angiogram is done, your healthcare provider will take out the catheter. Since the place where the tube went into your body may bleed, you might feel someone pressing a bandage on it for at least 15 minutes to prevent or stop bleeding. You might feel some soreness there afterward. If the catheter was in your arm, your provider will put on a tight bandage there.
You may need to lie on your back for a few hours if the catheter was in your groin. You can usually go home the same day as your coronary angiogram. While many people who have a stent placed can still go home the same day, if your procedure was complex or performed in the afternoon, you should be prepared to stay the night.
Because you had anesthesia, you’ll need someone to drive you home after your provider discharges you on the same day. For your safety, you should have someone drive you home even if you’re sent home the next day.
You may feel tired after your coronary angiogram and your wound may be sensitive or bruised for a week or more. Your provider may tell you to limit your activities for a couple of days after you get home.
An experienced healthcare provider can do coronary angiography safely. Serious complications are rare. People who are older or who have diabetes or kidney disease are more likely to have complications. The risks of a coronary angiogram include:
You may be able to see your X-rays while your provider is doing the test or after it’s done. Your provider will share the results with you after your coronary angiogram is over.
Contact your healthcare provider if you have a lot of bleeding or swelling at the place where your provider put in the catheter. You should also tell your provider if you’re having difficulty with circulation in your arms or legs.
A note from Cleveland Clinic
The information your provider learns from your coronary angiogram will help them make a diagnosis and a treatment plan for you. It’s important to ask questions if there’s anything you don’t understand when your provider explains your diagnosis and treatment. Be sure to follow your provider’s instructions to prepare for treatment and keep taking any medicines they ask you to take.
Last reviewed by a Cleveland Clinic medical professional on 11/29/2021.
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