Angiography

Page last reviewed: 13/07/2011

Angiography is a type of X-ray examination that creates detailed images of the arteries (blood vessels) and the blood flow inside them. These images are called angiograms.

Angiography involves injecting a special dye, called contrast medium, into the blood vessels. On the angiogram, this shows any abnormalities inside the blood vessels.

What is angiography used for?

Angiography is used to explore blood vessels in different parts of the body including:

  • the brain,
  • the heart,
  • the kidneys,
  • the eyes, and
  • the extremities (arms and legs).

Types of angiography

Types of angiography include: 

  • cerebral angiography (brain),
  • coronary angiography (heart),
  • pulmonary angiography (lungs),
  • renal angiography (kidneys),
  • lymphangiography (lymph vessels), and
  • extremity angiography (arms or legs).

X-ray

An X-ray is a painless way of producing pictures of inside the body using radiation.

Blood

Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.

Arteries

Arteries are blood vessels that carry blood from the heart to the rest of the body.

Veins

Veins are blood vessels that carry blood from the rest of the body back to the heart.

Heart

The heart is a muscular organ that pumps blood around the body.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Brain

The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Blood vessels

Blood vessels are the tubes in which blood travels to and from parts of the body. The three main types of blood vessels are veins, arteries and capillaries.

Coronary artery bypass

A coronary (heart) bypass is surgery to redirect the flow of blood around a clogged artery, by creating a new pathway for the blood to travel in.

Aneurysm

An aneurysm is a blood-filled sac that forms in a weakened part of a blood vessel.

Cysts

A cyst is a fluid-filled sac or cavity in the body.

Congenital

Congenital means a condition that is present at birth. The condition could be hereditary or develop during pregnancy.

Page last reviewed: 13/07/2011

Angiography enables X-ray images to be taken of the blood vessels and internal organs to find the cause of a health problem.

X-rays are normally used to produce images of dense or solid tissue, such as bone. Blood does not show up on normal X-ray images. However, injecting a contrast medium (liquid dye) into the blood vessels enables any blockages or structural problems to be seen.

Detecting problems with the brain

Cerebral angiography looks at the blood vessels in your head and neck. In particular, it gives a good view of the carotid arteries (the two arteries located on either side of your neck that supply blood to your brain). Cerebral angiography can be used to:

  • investigate a cerebral bleed (bleeding in the brain),
  • assess the condition of the blood vessels that supply the brain,
  • identify the blood supply to a brain tumour (a growth of cells in the brain), and
  • determine whether an operation to remove a tumour is possible.

Detecting blockages in blood vessels

Angiography shows if the blood vessels are narrow, irregular or blocked. It is used to detect diseases that alter the blood vessel channel.

It can show, for example, atherosclerosis, where fatty deposits known as plaques build up along the inner lining of the blood vessels. As a result, the blood vessels become hard and narrow and this restricts the flow of blood, causing vital organs to stop working properly.

Detecting problems in the coronary arteries

Coronary angiography is used to check the condition of the coronary arteries. The coronary arteries are the two major arteries that supply blood to the heart.

If a coronary angiography identifies areas of the coronary arteries that are narrowed or blocked, treatment using a balloon angioplasty or a coronary artery bypass may be recommended. See Useful links for more information about these.

Other uses

Angiography can also be used to:

  • locate any internal bleeding,
  • check the blood vessels in other vital organs such as the kidneys, liver and aorta (the body's largest blood vessel), as well as the extremities (arms and legs),
  • detect blood clots (thrombosis),
  • detect bulges (aneurysms) on blood vessel walls that are caused by weaknesses in the walls,
  • detect abnormalities such as cancerous and non-cancerous tumours (growths), cysts or congenital (present at birth) defects, and
  • investigate an injury to an internal organ.

Angiography is often used to help decide whether surgery is an appropriate treatment. It can also be used to help plan surgery.

Glossary

Brain
The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.
Arteries
Arteries are blood vessels that carry blood from the heart to the rest of the body.
X-ray
An X-ray is a painless way of producing pictures of inside the body using radiation.
Liver
The liver is the largest organ in the body. Its main jobs are to secrete bile (to help digestion), detoxify the blood and change food into energy.
Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Heart
The heart is a muscular organ that pumps blood around the body.
Blood vessels
Blood vessels are the tubes in which blood travels to and from parts of the body. The three main types of blood vessels are veins, arteries and capillaries.
Kidneys
Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.
Aneurysms
An aneurysm is a blood-filled sac that forms in a weakened part of a blood vessel.
Lungs
Lungs are a pair of organs in the chest that control breathing. They remove carbon dioxide from the blood and replace it with oxygen.

Page last reviewed: 13/07/2011

If you have problems with your circulation, your GP may recommend angiography to find out what is causing the problem. The results will help decide what the treatment options are.

As blood vessels supply blood to every part of your body, any part can be affected by circulation problems. The major internal organs (your heart, brain and kidneys) and the extremities (your arms and legs) are affected if the blood supply to them is changed by blockages or arterial disease (disease of the arteries).

Problems caused by serious arterial disease include:

  • strokes,
  • heart attacks,
  • gangrene (tissue death), and
  • organ failure.

Therefore, problems with your circulation should be investigated as soon as possible. The condition of your arteries can be assessed and appropriate treatment options suggested.

Glossary

Tissue
Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection or storing fat.  
Arteries
Arteries are blood vessels that carry blood from the heart to the rest of the body.
Veins
Veins are blood vessels that carry blood from the rest of the body back to the heart.
Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Heart attacks
A heart attack happens when there is a blockage in one of the arteries in the heart.
Heart
The heart is a muscular organ that pumps blood around the body.
Brain
The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Page last reviewed: 13/07/2011

In most adults and older children, an angiography is carried out while the person is awake. Sometimes a local anaesthetic is used to numb the area where the needle is inserted. With younger children a general anaesthetic (to put them asleep) may be used.

The angiography procedure

First of all, contrast medium (a special dye) is injected into an artery. The dye is not harmful. It leaves the body in the urine a few hours after the procedure. After the contrast medium is injected, blood vessels can be viewed and X-ray images taken.

If the carotid, coronary or cerebral arteries are being examined, a catheter (a thin, flexible tube) is inserted into an artery in your leg, arm or groin. The femoral artery, located in the thigh, is often used because it provides good access to the heart and surrounding blood vessels.

Before inserting the catheter, a local anaesthetic is normally used to numb the area around the insertion point. A long, thin wire with a smooth and rounded tip is inserted into the artery. X-ray images are used (fluoroscopy) to guide it to the right place in the blood vessel being examined.

When the guide wire is in place, the catheter can be inserted along the wire and into the blood vessel. Once the catheter is in, the guide wire is removed, and the contrast medium is injected into the blood vessel through the catheter.

The procedure is not painful, but as the contrast medium is being injected you may experience slight discomfort for a few seconds in the affected area.

After the contrast medium is injected, a radiologist (a specialist trained in looking at images of the inside of the body) is able to view your blood vessels on a monitor, and a series of X-ray images is taken.

Angiography generally takes between 20 and 90 minutes to do, depending on the complexity of the investigation. You will usually be allowed to go home on the same day, but in some cases you may stay in hospital overnight.

See Useful links for more information about angiography.

Digital Subtraction Angiography

Digital Subtraction Angiography (DSA) uses computerised X-ray equipment to take images of the body's organs and blood vessels. As with the standard angiography procedure, contrast medium is injected into your blood vessels so that they show up clearly on the X-ray images.

Before the procedure, the person testing you will explain the DSA test to you so that you know what to expect. Throughout the procedure your care team may include:

  • a consultant,
  • a radiographer (a health professional who is trained in taking X-rays of the body),
  • a nurse, and
  • an electrocardiograph technician (who will monitor your pulse and heart rate throughout).

You will be asked to lie on an X-ray table. The procedure may last from 30 minutes to three hours, depending on the exact test you are having. DSA is not painful, although as with the standard angiography procedure you may experience some discomfort while the contrast medium is being injected.

The X-ray equipment can be rotated 360°, and is used to take a number of complex images. The radiographer can enhance and edit the images, removing any unwanted surrounding detail so that only the shape of the blood content of the vessels is visible.

You will able to go home either on the same day or the day after.

Fluorescein angiography

Fluorescein angiography is another form of angiography that enables the tiny blood vessels in the retina (the light-sensitive area) at the back of your eye to be examined in detail. It is often used to investigate posterior vitreous detachment, which is an eye condition that causes the tiny blood vessels in the retina to burst and bleed.

Before they start, the person carrying out the test will explain the procedure to you. Inform them of any allergies you may have. Also, tell them if you think that you may be pregnant.

At the start of the procedure, you will be given eye drops to dilate (widen) your pupils. A special dye that shows up brightly under ultraviolet light will be injected into your bloodstream through a blood vessel either in your hand or arm.

Once the dye has been injected, as it enters the blood vessels in your eye a series of photographs is taken. Your eye may also be examined with an ophthalmoscope (an instrument with a light on the end that creates a magnified image of your eye). This allows abnormalities to be identified.

Fluorescein angiography is a painless procedure. However, during the injection, you may experience a hot flush that lasts for a few seconds. Afterwards, your skin may appear pale yellow and your urine may be bright green. These side effects are usual and will disappear after a few days.

You will be allowed to go home on the same day, but you must not drive. For a short time your vision will be blurred from the eye drops and from the bright light of the camera. Arrange for someone to give you a lift home from the hospital.

Glossary

Retina
The retina is the nerve tissue lining the back of the eye, which senses light and colour and sends it to the brain as electrical impulses.
Catheter
A catheter is a thin, hollow tube usually made of rubber that is placed into the bladder to inject or remove fluid.
Local anaesthetic
A local anaesthetic is a drug that is injected by needle or applied as a cream, which causes a loss of feeling in a specific area of the body.
Blood vessels
Blood vessels are the tubes in which blood travels to and from parts of the body. The three main types of blood vessels are veins, arteries and capillaries.
X-ray
An X-ray is a painless way of producing pictures of inside the body using radiation.
Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Anaesthetic
Anaesthetic is a drug used to either numb a part of the body (local), or to put a patient to sleep (general) during surgery.
Vein
Veins are blood vessels that carry blood from the rest of the body back to the heart.
Heart
The heart is a muscular organ that pumps blood around the body.
Arteries
Arteries are blood vessels that carry blood from the heart to the rest of the body.

Page last reviewed: 13/07/2011

As with any procedure, there are risks involved. So before having any form of angiography, you should discuss the potential complications with your care team.

Coronary angiography

Coronary angiography is a common procedure and serious complications are fairly rare. However, minor complications can often occur, which include:

  • Bleeding and bruising at the site of the injection (usually the groin area) is common, although it should heal quickly,
  • blood vessel damage caused by the catheter as it is threaded up into the heart (although this is very rare), and
  • an allergic reaction to the contrast medium (dye).

Other, rarer complications of the procedure include:

  • cardiac arrhythmia (irregular heartbeat), which usually clears up without treatment,
  • kidney damage caused by the dye,
  • blood clots that can cause serious problems, such as a heart attack or stroke,
  • hypotension (low blood pressure), and
  • a build-up of blood or fluid around the heart, which can prevent it from beating properly.

Following coronary angiography, the risk of developing complications is increased in people who are 75 or over. The risk is also greater in women and those who are having coronary angiography in an emergency.

Cerebral angiography

As with coronary angiography, serious complications following cerebral angiography can sometimes occur but they are rare.

Bleeding and bruising at the site of the injection is common, although it will usually heal quickly.

Delayed bleeding is rare, but as a precaution you will be kept under observation for four to six hours afterwards.

More serious complications of cerebral angiography are listed below. 

  • A stroke is the most serious risk, but is rare. The likelihood of having a stroke that causes permanent paralysis (muscle weakness) is approximately one in 1,000.
  • An allergic reaction to the anaesthetic, painkilling medication or dye is also rare and, if it does occur, can usually be controlled with medication. Serious, life-threatening reactions develop in approximately one in 50,000 to one in 150,000 people.
  • A blocked or damaged blood vessel at the location of the injection (in the groin) could occur, which may temporarily affect the blood supply to your leg. Sometimes, emergency surgery may be required to clear a blocked blood vessel.
  • There can be other, rare, complications, such as a blood clot, which can affect other organs.

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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