CT Coronary Angiogram

This information leaflet has been produced to give you general information and hopes to answer most of your questions when requiring a CT Coronary Angiogram. It is not intended to replace the discussion between you and the healthcare team, but may act as a starting point for discussion. If after reading it you have concerns or require further explanation, please discuss this with a member of the healthcare team.

Please contact us prior to your scan if:

  • You are, or might be, pregnant
  • You weigh more than 200kg or 31 stone

What is a CT scan?

A CT Coronary Angiogram is a test that uses a special x-ray machine to produce detailed pictures of your heart. These pictures are examined by a Radiologist or Cardiologist (doctors who specialise in reading cardiac images). They will help to assess if you have any narrowing or blockage of the blood vessels (coronary arteries) around your heart. The CT scanner is an open ring-like structure which resembles a giant doughnut. It is not a tunnel as everyone expects.

How should I prepare for my CT Coronary Angiogram?

Prior to your referral for a CT Coronary Angiogram, you will have a brief pre-assessment in clinic with one of our Cardiology Nurse Practitioners. Your heart rate and blood pressure may be checked and blood samples may be required.

For the test you will need to be relaxed and your heart rate will need to be slow and stable. This is to ensure we obtain clear images of your coronary arteries. Depending on your heart rate, you may be given drugs to slow your heart rate to be taken 12 hours and two hours before the test.

For 12 hours before your procedure you should not have any caffeinated or decaffeinated drinks, chocolate or medication that contains caffeine, as these will raise your heart rate. Please do not eat for four hours before the scan.

Unless you have been informed by a doctor to restrict your fluid intake, please ensure you are not dehydrated on the day of your scan and aim to drink three to four cups of clear fluid before your appointment.

Do not undertake any exercise or physical activity that will raise your heart rate in the four hours before the test. Please try to avoid driving or cycling to your appointment. If you have asthma and use an inhaler or have been prescribed GTN spray, please bring these with you on the day of your scan.

Can I bring a relative or friend?

Yes, but for reasons of safety they will not be able to accompany you into the CT scan room except in very special circumstances.

Can I take my prescribed medicines as usual?

Unless specifically told otherwise by the CT Appointments Team or the Cardiology Nurse Practitioner, you can continue to take all your usual medication.

What happens at the hospital before the scan?

When you arrive in the department you will be greeted by the Reception Team and Radiology Assistants.

You will be asked to change into a hospital gown. It is advisable to leave any valuables at home.

A radiographer (member of the Radiology Team trained to carry out scans) will put a cannula (needle) into a vein in your arm or back of your hand. During the scan you may be given an injection of x-ray dye (contrast). This helps to highlight your coronary arteries more clearly on the CT images. We will also ask you a number of questions about your medical history.

We will also check your heartrate when you arrive and if it is faster than the ideal rate, we may give you some medication called beta-blockers to slow it down. This may be in the form of a tablet or an injection and can take up to one hour to work. As soon as your heartrate is beating at the right pace, we will perform your scan.

The Radiologist or Cardiologist will explain the CT examination to you and what to expect. You can ask any questions you may have.

What happens during the scan?

You will be asked to lie on your back on the scanning table. We will place electrodes (small, sticky patches connected to leads) on your chest. The electrodes are connected to a monitor that records your heart during the test. The Radiologist or Cardiologist will give you a spray of GTN under your tongue. This is to open up the arteries in the heart as much as possible making it easier to assess them on the scan. You may get a slight headache or feel a little dizzy from this, but this will pass after a short time.

The scanner will then be triggered to take pictures at certain points during your heartbeat by moving your body through the ‘doughnut’ shaped hole (gantry). This gives high quality images of your heart and arteries. If you need to have x-ray dye, this will now be injected. The dye may give you a metallic taste in your mouth and a ‘hot-flush’. Some people feel as though they have an urgency to pass urine. All of these sensations pass in a couple of minutes. If you have any questions about this please ask a member of staff.

You will need to lie very still while each picture is taken and you may be asked to hold your breath for a moment. We understand that some people have difficulty holding their breath- please tell us at the time if this is a problem for you.

The scanner is not noisy and the examination should not be painful. During the scan, the Radiographer and the Radiology Assistant will be in an adjacent control room. You will be able to talk to them via intercom and you will be observed at all times.

How long does the scan take?

The actual scan itself usually lasts between 15 and 20 minutes, but you may be in the department one to two hours.

We will try and keep to your appointment time but occasionally we have to scan patients urgently at short notice. This means your appointment could be delayed. We will let you know if this is the case.

Are there any risks?

As with all x-rays, CT scans use radiation. The level of radiation used is small and the benefits of the scan are thought to outweigh any risks.

The x-ray dye injection contains iodine which can cause an allergic reaction in a few people. You should tell the Radiographer if you have had an allergic reaction to iodine or x-ray dye in the past or if you have any other allergies.

Very rarely the x-ray dye may cause kidney damage, most commonly in people known to have kidney problems. The risks will have been assessed by your doctor. Occasionally precautions may be taken prior to your scan and you will be informed of this by our CT Appointments Team or Radiology Nurses.

Rarely, after an injection, the x-ray dye can leak outside the vein and cause temporary swelling and discomfort in the arm requiring a cold compress. Very rarely a more extensive injury to the skin and soft tissue at the injection site can occur. This is unlikely to happen but if it does we will give you further instructions and advice.

You will probably not notice any side-effects from the beta-blockers but it is important to tell us if you suffer from asthma. If your heart rate becomes too slow medication may be required to reverse the beta-blocker, but this is extremely rare.

Despite these slight risks, your doctor believes it is advisable that you should have this examination. Do bear in mind that there may be greater risks from missing a serious disorder by not having your scan.

What happens after the examination?

We will ask you to wait 30 minutes before you leave the CT Department after your scan. You can eat and drink as normal. You will be provided with a hot drink and biscuits while you are waiting. We will also advise you to slightly increase your fluid uptake for the rest of the day.

You should be able to drive home afterwards and resume normal activities.

How do I find out the results of my scan?

You will not get the results on the day. The pictures taken during the scan need to be carefully studied by the radiologist or cardiologist. The doctor who asked us to perform your test will receive your results, which is usually within seven days. The hospital will contact you with a follow-up outpatient appointment. If after three weeks they have not contacted you, please ring the hospital switchboard on (0191) 482 0000 and ask to speak to your Consultant’s secretary.

Who do I contact if I have concerns?

Should you require further advice on the issues contained in this leaflet, please do not hesitate to contact the CT Department or Cardiology Nurses on (0191) 445 2094.