Angiography

Information about an angiography procedure, what it involves and what to expect when your child comes to Great Ormond Street Hospital (GOSH) to have it.

Angiography is a procedure that allows doctors to look at blood vessels in detail using X-rays. It is used to help make a diagnosis or monitor the effects of a treatment. Angiography produces an angiogram, which is an image of the blood vessels in the body. An angiogram looks a little like a road map, showing the path of blood vessels and their junctions. Any part of the body can be studied using angiography, so it is used for a wide variety of conditions. For example, a cerebral angiogram looks at blood vessels within the brain- this is explained in a separate leaflet.

Angiography can be used to look at abnormal blood vessels in detail. Blood vessels can narrow as part of an illness affecting the entire body, such as vasculitis or neurofibromatosis. Sometimes just the arteries supplying the kidneys can become narrowed and this is called renal artery stenosis.

Angiography can also be used to look at normal blood vessels, to plan future surgery or treatment of an organ supplied by those blood vessels. Your child’s doctor will explain why the angiogram is needed and which part of the body is affected. It is carried out in the Department of Interventional Radiology by a specialist who uses imaging to guide procedures.

A narrowed blood vessel causes problems because it causes reduced blood flow to the part of the body it is supplying.

Narrowing of some arteries, especially the ones that supply blood to the kidneys, can also lead to high blood pressure.

In other diseases, blood vessels can be widened or dilated (sometimes called an aneurysm) and this can also cause problems.

Sometimes there is also abnormally fast flow through blood vessels (a shunt). An angiogram is helpful in allowing doctors to study the blood flow through these blood vessels.

Your child may need to come to GOSH for a pre-admission assessment. This is to check that they are well enough to have the angiogram.

This appointment may involve taking blood samples and other tests.

You will have already received an admission letter which contains more information on how to prepare for the procedure.

If your child takes regular medication, please speak to your child’s team about when to stop these before the procedure.

Your child needs to be fasted for the procedure for the general anaesthetic. As a general rule:

Food and milk:

• Breast-fed babies- can have their last feed three hours before the procedure. Breast milk is digested faster than solid food or formula.
• Bottle-fed babies and children- can have their last milk feed, food or milk drink, six hours before the procedure. They should not have any food or milk after this time.

Water:

• All babies and children can have a drink of water (but no other fluids), until one hour before the procedure.

Please follow these instructions carefully, otherwise your child’s procedure may be delayed or even cancelled.

Your child will be admitted to a bed on a ward.

Please note, that the person bringing your child to the procedure should have ‘parental responsibility’ for them. Parental responsibility refers to the individual who has legal rights, responsibilities, duties, power and authority to make decisions for a child. If the person bringing your child does not have parental responsibility, we may have to cancel the procedure.

An anaesthetist will come and talk to you about your child’s anaesthetic. A specialist will explain the procedure in more detail, discuss any questions you may have and ask you to sign a consent form giving permission for your child to have the procedure. If your child has any medical problems, please tell the specialists.

A contrast liquid is used during the procedure to help make the images clearer. This is removed from the body through urination (weeing), so please tell the doctors if your child has any kidney problems.

You and your child will then be brought to the Interventional Radiology (IR) suite within the X-ray department for the anaesthetic and the procedure.

Once your child is under general anaesthetic, the radiologist will insert a needle into an artery (large blood vessel), using ultrasound to guide them. Some local anaesthetic is injected into the skin first, to make the area numb for a few hours, and a very small cut is made in the skin, through which the needle is placed. We will usually use the groin artery (femoral artery), even if the angiogram is needed for another part of the body as it is the easiest to access.

A soft guide wire is threaded over the needle, which is then removed. Finally, a catheter (thin plastic tube) is threaded over the guide wire into the artery, and the guide wire is removed.

The catheter is then threaded through the arteries until it is in the area needed. X-rays and contrast are used at various points to guide the catheter in the right direction and to check that it has reached the area that needs to be scanned. Further X-rays are then taken as the contrast flows out of the catheter into the blood vessels so that they can be seen clearly from several angles and give detailed information.

If your child is having an angioplasty during the same procedure, a small balloon is inserted via the catheter, which is inflated when it reaches the narrowed section. This stretches the walls of the blood vessel so that blood flow through it is improved. X-rays are used to check that the balloon is in the right place and to measure how much it is inflated.

At the end of the procedure, the catheter is drawn back through the blood vessels and removed. No stitches are needed where the catheter was inserted, as only a small mark is left, which should heal completely within a few days.

Your child will return to the ward after they have recovered from an anaesthetic. Some children feel sick and vomit after a general anaesthetic. Your child may have a headache or sore throat or feel dizzy, but these side effects are usually short-lived and not severe. Your child can start eating and drinking as normal once they feel like it.

The doctors will come to check your child’s progress on the ward and will give you some information about what they have done during the procedure.

The nurses on the ward will check the area where the catheter was inserted regularly. Your child will need to lie flat on their back in bed for at least four hours afterwards. This will reduce the risk of bleeding from the catheter site. They will also check your child’s vital signs, including pulse, breathing and blood pressure regularly. Occasionally an overnight stay may be required for further blood pressure monitoring.

Your child will usually be able to go home when their vital signs are normal, the catheter site is not bleeding, and they have had something to eat and drink.

There will be a small dressing in the area, which you should keep in place and dry for at least 48 hours.

We advise that your child avoids sport or PE for at least five days after the procedure.

You should call the hospital ward if:

• Your child starts bleeding from where the catheter was inserted. If bleeding happens, apply pressure to the area straight away.
• Your child is in a lot of pain and pain relief does not seem to help.
• The area where the catheter was inserted looks red, swollen and feels hotter than the surrounding skin.
• The leg where the catheter was inserted looks or feels different to the other leg.
• Your child is not drinking any fluids after the first day back at home.

You can call the ward by calling the GOSH switchboard and asking for the ward your child was discharged from.

Telephone: 020 7405 9200

If you are unable to get through, please call NHS111 by dialling 111.

The pictures taken during the procedure need to be studied carefully by the radiologist, who will write a report for your child’s doctor. The results will not be available straightaway and usually we will make an outpatient appointment to discuss them with you.

Your child will be having the procedure under general anaesthetic. Every anaesthetic carries a risk, but this is extremely small.

Complications of angiography are extremely rare.

There is only a small risk of infection. Your child may bleed from the area where the catheter was inserted, but this can be minimized by applying pressure for a few minutes after the procedure. There is often a bruise in the area, and it might feel a bit sore. Pain relief such as paracetamol or ibuprofen is usually enough to deal with this, unless your doctor has told you not to take this.

There is a very small chance that the blood vessels being studied could be damaged, either by a blockage or a tear in the blood vessel wall. Damage to the blood vessels is very unlikely as the progress of the catheter through the blood vessels is checked frequently using x-rays.

Rarely a clot can form in the leg artery where the catheter was inserted, or the artery can go into spasm. This may affect the blood circulation in the leg. If this happens, it may be necessary to give medicine to thin your child’s blood for a short time. Rarely, further treatment may be required.

Long-term, the artery wall where the catheter went into the vessel (usually the groin), may be weakened by having had the catheter there, as the vessel wall may lose some of its elasticity.

With the high pressure of the blood flow through the vessel, this may lead to a small bulge in the vessel wall (like a weakness in a hosepipe wall). We call this a pseudoaneurysm. If this happens, you might notice a small bulge under the skin near where the catheter went in, which has a pulse in it. This is not dangerous, but it should be treated. The treatment options are usually straightforward. If you notice this, please inform your family doctor (GP) or hospital consultant.

It is extremely unusual to have an allergic reaction to the contrast. If your child has any allergies, please tell the radiologist before the procedure starts. The contrast is removed from your child’s body by the kidneys and is passed when urinating.

The procedure does involve the use of X-rays. The levels that are used are low dose and therefore low risk. If you have any concerns regarding the use of radiation, please discuss this with the person performing your procedure beforehand.

As the procedure involves the use of X-rays, legally, we have to ask anyone over the age of 12 whether there is any chance they might be pregnant.

We will also ask for the first date of their last period (if started). This is to protect babies in the womb from receiving unnecessary radiation.

The doctor may be able to gain information about your child’s blood vessels using another type of imaging procedure, such as an MRI or CT scan. Usually, angiography gives more detailed pictures than other types of scans.

Angiography is often just one of many tests and procedures your child will have to help the doctors make a diagnosis or monitor treatment.

Angiography is usually only carried out if less invasive tests cannot provide the necessary information.

If you have any questions, please speak to you child’s doctor or nurse or call Interventional Radiology.

Telephone:020 7405 9200 extension 7943.

You can also contact us through MyGOSH.