About Coronary Angiography
Coronary Angiography, or Angiogram, is a minimally invasive procedure which is done to show the amount of coronary artery disease in the blood vessels that supply the heart. Coronary arteries can become clogged from a build-up of cholesterol, cells or other substances (plaque). This can reduce the flow of blood to your heart, causing chest pain, shortness of breath, angina or a heart attack. An angiogram will help the cardiologist to decide the best course of treatment for your needs, including Coronary Angioplasty, Coronary Bypass Surgery or medicinal treatment.
Common indications for this procedure include:
- To investigate symptoms such as chest pain and shortness of breath.
- To investigate abnormal heart rhythms.
- To further investigate abnormal screening tests.
- To assess bypass grafts or coronary arteries that have been previously stented.
You will be admitted to hospital to have your Coronary Angiogram, which is usually done as a day procedure. During the procedure, contrast dye is injected into the coronary arteries via a small, thin tube called a catheter. The cardiologist will assess the artery using X-ray as the dye passes through it.
You will be asked to fast for 4 hours prior to the procedure. This includes food and water, however you should be able to take most regular medication with a small amount of water.
Your cardiologist will advise if there are to be any changes to your usual medications prior to the procedure. If you are on Warfarin, you will usually be asked to stop taking this for 3-4 days prior. DO NOT stop taking Aspirin or Plavix / Iscover.
If you are a diabetic, you may need to stop taking insulin the night before and/or the morning of your test to avoid low blood sugar levels.
Take other medication as usual on the day with a small amount of water. If you are unsure of any of the above, please check with your doctor.
Please advise the staff if you are aware of any allergies you may have. X-ray dye (contrast solution) used in in this procedure contains Iodine. If you have an allergy to Iodine, you must inform your doctor prior to this procedure.
You may be given a mild sedative before the procedure to help you relax, but you will remain awake for the procedure.
X-Rays and blood tests
Bring with you any chest X-rays you've had from the last 6 months.
Please inform the nursing staff on admission if you have had a recent blood test and which pathology group you attended, otherwise you may need to have a blood test done on admission.
The Coronary Angiogram is performed in a cardiac catheter laboratory under a local anaesthetic. The lab has X-ray equipment and monitors to assist the cardiologist in taking pictures of the coronary arteries.
The procedure takes approximately 30 minutes.
Electrodes are attached to your arms, chest, legs and back to monitor your heart rhythm. Your blood pressure and oxygen saturation will also be monitored throughout the procedure.
A small amount of local anaesthetic agent is injected into the skin. You may briefly experience a cold or a mild stinging sensation. Most patients report that this is the only discomfort associated with this procedure. A small incision is made from an artery in your right groin, right elbow or right wrist, depending on your doctor.
A hollow needle is inserted into the artery and a small tube 6cm to 9cm in length called a "sheath" is inserted so as to gain access to the circulatory system. You may feel a bit of pressure while the sheath is being inserted. After that, you should not feel any discomfort.
Insertion of Cardiac Catheters
The catheters (long tubes, approximately 2mm in diameter) are inserted into the artery by means of a flexible guide-wire and connected to a series of taps that allow ongoing blood pressure monitoring. A separate catheter is used for the right and left coronary arteries. You will not feel any sensation of the catheters moving inside your body.
An X-ray dye is injected into the coronary arteries via the catheter. This solution reveals any blockages or narrowing of those arteries. The X-ray contrast is cleared away by the kidneys.
A third catheter called a "Pigtail" may be placed into the main pumping chamber of the heart (the left ventricle). When the contrast is injected into this catheter, you may experience a sudden warm sensation which will only last for a few seconds.
Taking the Pictures
During the test you will be asked to take deep breaths which you will have to hold for a few seconds while the X-ray pictures are being taken. Images of the arteries are then recorded on digital X-ray, which will be reviewed by your cardiologist.
Removal of the Sheath
After the procedure, the attending cardiac nurse will remove the sheath and apply pressure to the puncture site, this can last up to 15minutes. After the risk of bleeding has passed and a seal has formed over the puncture site, a bandage will be applied to apply further pressure to the site.
After the procedure, you will be taken back to the ward for observation. For leg punctures, you will need to rest in bed for 2-4 hours to reduce the risk of groin bleeding.
You will be reviewed by your doctor after the procedure. They will fully discuss the findings and the implications they have on your overall cardiac care, either when they see you prior to discharge or at a follow-up appointment.
Nursing staff will advise you on follow-up care at home.
It is normal to have a small amount of bruising, a small lump (about the size of a pea) and/or a small amount of pain for the first week. If you have a lot of pain, a large lump or a large bruise you should have this reviewed by your GP or cardiologist.
In order to protect your artery, avoid strenuous exercise and heavy lifting for the first week after the procedure.
Possible Risks and Complications
The risks of coronary angiography depend on:
- How bad your coronary artery disease is;
- How well your heart is pumping;
- How old you are;
- How healthy your other organs are;
- If you have had a previous bypass operation.
The table below outlines some of the more serious risks of the procedure.
|Heart Attack||1 in 1000|
|Stroke or Mini-stroke (TIA)||1-2 in 1000|
|Perforation of large blood vessels or heart||1 in 1000|
|Urgent open heart surgery||1 in 1000|
|Urgent balloon angioplasty||1 in 1000|
|Death||1 in 1000|
|Blood Vessel Complications|
|Blood clot||1 in 1000|
|Major bleeding||Less than 1 in 100|
|Pseudo-aneurysm formation: blood clot with connection to the artery lumen||Less than 1 in 100|
|Need for surgery because of blood vessel complications||Less than 1 in 100|
|Skin reaction||Less than 1 in 20|
|Severe life-threatening reaction requiring resuscitation||Less than 1 in 1000|
|Abnormal Heart Rhythm|
|May require electrical shock treatment or temporary / permanent pacemaker||Less than 1 in 500|
|Deterioration in Kidney Function||Less than 1 in 100|
|Infection||Less than 1 in 1000|
|Skin Injury from Radiation||Less than 1 in 10,000|