CT Coronary Angiograms (Cardiac CT)

All patients that have been referred for a CT Coronary Angiogram will receive copies of our CT Coronary angiogram information leaflet when they receive their appointment letter. These may also be found at the bottom of this page or in the PILS link on the front page.

Before the scan

You will be referred for this test by one of the clinicians in the hospital; they will send a request to the CT bookings clerk who will send out an appointment for you. There may be scope to change this appointment time if it does not suit you.

Please contact the radiology department before your scan if you are:

  • Pregnant
  • Asthmatic
  • Allergic to iodine or X-ray dye
  • Diabetic and taking metformin
  • Have an underactive thyroid and are taking thyroxine


You will need to have someone to drive you to and from the hospital for this test. This could be a friend or relative.

For their safety, your relative or friend will not be able to accompany you into the examination room.


For a 24 hour period before your scan, you must not take:

  • Food or drinks that contain caffeine, such as tea, coffee, fizzy drinks and chocolate.
  • Stimulant medicines such as antihistamines, decongestants or pain relief containing caffeine.

Please do take any other medicines that you need unless otherwise instructed.


It is important that you are as relaxed as possible before your scan, as this helps to keep your heart rate low and results in clearer images. Caffeine and certain medicines can raise the heart rate, meaning we will be unable to scan you.


At your appointment

You will be given a gown to wear during the scan. Metal objects, such as necklaces and bra fastenings, affect the images and must be removed

prior to the examination while you are changing.


You will then be taken to a private area where a radiology nurse will ask you some questions about your health, medications you might be taking and take your heart rate and blood pressure using a monitor. If your heart rate is too fast to scan your heart clearly, you may be given some medication before and during your scan.


This slows your heart rate and results in much more accurate images.


A cannula will be placed into a vein in your arm and through this you will receive the injections of dye during your scan.


What will happen during the scan?


You will be taken into the CT scanning room where your identity will be checked. The radiographer will explain the procedure to you and answer any questions you might have. If you agree to have the scan, you will be asked to lie down on the couch.

You will be attached to the heart rate monitor and the pump which injects the dye through the cannula.

At this point you may be given a tablet to place under your tongue. The tablet is called GTN, or glyceryl trinitrate, which relaxes the vessels around the heart, enabling them to be imaged. You may find that the tablet doesn’t dissolve completely; it can be swallowed or spat out after the procedure is finished.

The couch will be moved slowly to position your chest within the ‘polo mint’. The radiographers will retire to the control room they but will be able to hear you talk over the intercom and see you throughout the scan.

During the scan, the couch will move in and out of the machine a few times.

You will need to hold your breath at certain times during the scan. This is very important in order to ensure clear and accurate images. The radiographers will explain the breathing instructions to you.

The radiographers will tell you over the speaker before you receive the injection.

When the dye is injected it is common to experience a ‘hot flush’ sensation, particularly across the neck and chest. This feeling goes away quite quickly and is normal. Many people experience the hot sensation around the rest of the body. Some people also get a metallic taste in their mouth. As the examination requires two injections of dye, you may experience these sensations twice.

Please expect to be in the department for at least 1-2 hours.

The scanning process will take up to twenty minutes. Sometimes there may be a delay in the department due to emergency cases which may result in you being seen later than your appointment time. We try to keep patients informed of any delays where we can.


What happens after the scan?


The cannula will be removed. You will be asked to wait in the department for at least 30 minutes if you had medication whilst in our care. During this time a nurse will check your heart rate and blood



Following the scan, you can eat and drink normally. You will not be able to drive yourself home.


The radiologists and the cardiologists will report the scan pictures and you will be able to discuss the results with your cardiologist during your next clinic appointment.

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