Angiogram Introduction: What is it and how does it work?

What is an angiogram?

An angiogram is a diagnostic test that shows how blood flows through the blood vessels. As blood vessels don’t show up clearly on an X-ray, a contrast dye is injected, and live X-ray is used. The images can show any problems in the blood vessels.

An angiogram allows a doctor to see how blood is circulating in specific parts of the body, including the heart, kidneys, legs or neck, to find the source of an issue in a blood vessel.

The process of examining the vessels for blockages is called angiography. The images or readings produced from the procedure are called an angiogram.

Types of angiography

Different types of angiograms are used to look at different parts of the body:

• Coronary angiogram: Specifically looks at the blood vessels of the heart. A coronary angiogram is performed by an interventional cardiologist.
• Peripheral angiogram: Performed on the peripheral arteries, this can be done by interventional radiologists, vascular surgeons, or interventional cardiologist, depending on the specific hospital.
• Cerebral angiogram: Checks the vessels in and around the brain. This will be performed by interventional neurologists or interventional radiologists, depending on the specific hospital.
• Pulmonary angiogram: Looks at the blood vessels that are supplying the lungs.
• Renal angiogram: Looks at the blood vessels supplying the kidneys.
• Venogram: Look at the veins in the body, particularly in the legs.

Who needs an angiogram?

An angiogram is performed if your doctor suspects there is a damaged, blocked or abnormal blood vessel(s). The procedure allows doctors to determine the extent of any damage and the source of the problem.

Angiography is also used to diagnose, or plan treatment for, a number of conditions, including:

• Atherosclerosis
• Aneurysm
• Blood clots
• Coronary artery disease
• Peripheral artery disease.

What happens during an angiogram?

Preparing for an angiogram

Your doctor may first want to check how well your blood clots and how your kidneys are functioning, via a blood test.

Your doctor will give you instructions to follow immediately before the test, which may include whether or not to stop taking any medications you are on, including medication for diabetes. Inform your doctor if you have an allergy to contrast dye as you may need special medications prior to the procedure.

You may be told not to eat anything from the night before the procedure and to only drink clear liquids on the day of the angiogram.

During an angiogram

On the day of the procedure:

• Arrange to have someone drive you home
• Bring a list of medications you are taking

Tell your doctor if you have diabetes. You will then meet with your doctor to discuss the procedure and what to expect in detail. You will then lie down on an X-ray table and the doctor will do the following:

• Apply anesthesia at the site where the catheter will go
• Use a needle to access the concerned blood vessel, and thread a wire through the needle
• Insert a catheter into the vessel
• Move the catheter through the vessel to the part to part to be examined
• Inject the contrast dye into the blood vessel
• Take the images
• Observe the contrast dye and its movement on the images.

If a blockage is found, an angioplasty or venoplasty may be performed, which involves inserting a small balloon and inflating it to push the blockage back against the wall of the blood vessel. This may further need a small metal tube called a stent placed into the vessel to keep it open permanently.

After an angiogram

You will rest for a few hours and then depending on your case, you may be admitted to the hospital or meet your doctor to discuss any instructions to follow at home.

Most people can go home the same day, but you should arrange for someone else to drive you. You should rest and avoid lifting any heavy objects for a few days.

If you are diabetic, your doctor will give you instructions on when to start taking your diabetes medication again.

If small blockages were found during the angiogram, you may be prescribed medication or given lifestyle advice, such as changing your diet and exercising more. If larger blockages are found, you may be referred for further treatment.