Angiography is an imaging technique used to assess the health of your blood vessels and how the blood flows through them.

If you have circulation problems, your doctor may recommend that you have angiography to find out what's causing the problem. The results can also help determine suitable treatment options.

Types of angiography

There are several different types of angiography that can be used depending on which area of the body needs to be examined, including:

• head and neck (cerebral angiography)
• heart (coronary angiography)
• lungs (pulmonary angiography)
• arms and legs (extremity angiography)
• kidneys (renal angiography)

Cerebral angiography

Cerebral angiography may be used if it's thought that the blood vessels that supply blood to your brain (the carotid arteries) have become narrowed, disrupting the flow of blood. This can be dangerous because it could trigger a stroke or transient ischaemic attack (TIA or mini-stroke).

If you've had a stroke, cerebral angiography can be used to find out if there's a narrowing in the blood vessels. In some cases, it may be able to pinpoint the underlying cause of a stroke.

Cerebral angiography can also help to identify an aneurysm (a bulge in the blood vessel wall in your brain) or a brain tumour. Studying the flow of blood to the tumour can help determine whether it's growing, which can be useful when planning treatment.

Coronary angiography

Coronary angiography may be used if you've had:

• a heart attack – a serious medical emergency, where the blood supply to the heart is severely reduced or suddenly blocked, usually by a blood clot
• angina – chest pain that occurs when the blood supply to the heart muscle is restricted

Coronary angiography may also be used if you have a heart condition that requires surgery. It helps to determine the most appropriate type of treatment for you. This could be:

• coronary angioplasty – a surgical procedure to widen blocked or narrowed coronary arteries using balloons and stents 
• coronary artery bypass graft – a surgical procedure to divert blood around narrow or clogged arteries using grafts so that blood flow to the heart is improved

Read more about coronary angiography.

Computerised tomography pulmonary angiography

Computerised tomography pulmonary angiography (CTPA) is often used to help diagnose a pulmonary embolism (a blockage in the pulmonary artery in one of your lungs).

CTPA involves injecting contrast dye into the blood vessels of your lungs and then taking a CT scan. If you have a pulmonary embolism, it will show up on the CT scan as a blockage in the blood flow.

Extremity angiography

Extremity angiography may be used if it's thought that the blood supply to your leg muscles has become restricted. This is known as peripheral arterial disease and it causes a range of symptoms, the most common of which is painful cramping when walking.

Imaging tests, such as an ultrasound scan or CT scan, may be used instead of angiography to investigate how severe the condition is.

Renal angiography

Renal angiography may be recommended if you have symptoms that suggest the blood supply to your kidneys has been blocked in some way.

These symptoms include:

• high blood pressure (hypertension) that doesn't respond to treatment with medication
• swelling in certain areas of your body, such as your feet, due to a build-up of fluid (oedema)
• kidney failure and symptoms of kidney disease, such as itchy skin and blood in your urine

Atherosclerosis

Atherosclerosis is a condition where the arteries become narrowed and hardened due to a build-up of fatty materials, such as cholesterol. The narrowing is often referred to as a plaque.

In the early stages, atherosclerosis doesn't usually cause symptoms, so medical tests such as angiograms are carried out when advanced disease is suspected.

Angiography is usually carried out if the symptoms are severe, or initial tests, such as a stress test, suggest that atherosclerosis is likely.

Read more about how atherosclerosis is diagnosed.

Other uses

Angiography can also be used to:

• locate the site of internal bleeding
• detect blood clots
• investigate injuries to organs
• plan surgery that involves the blood vessels