Having a Cardiac CT Scan
Having a Cardiac CT Scan
Patient Information
Radiology Service
- Author ID: LW / KG
- Leaflet Ref: Rad 027
- Version: 5
- Leaflet title: Having a Cardiac CT scan
- Last review: September 2025
- Expiry Date: September 2027
Introduction
If this information does not answer your questions, please contact the computed tomography (CT) Department where a member of staff will be pleased to help you:
CT Department
Telephone: 01942 822368
Please pay attention to your appointment letter. Your scan may be performed at either Wigan Royal Albert Edward Infirmary, or Leigh Infirmary. If you attend the wrong site, you will likely be turned away without a scan.
For health and safety reasons, please contact the CT Department if your weight is equal to or more than 222 Kg (35 stone), as the CT scanner has a weight limit.
What is a Cardiac CT scan?
It is a specialist scan which provides very detailed images of your heart and the blood vessels (coronary arteries) that supply blood to the heart.
What does the scanner look like?
A picture of the scanner is shown below. The scanner is open at both ends and you can speak to the staff at all times. You will be asked to lie on a bed which will move slowly through the scanner whilst it takes the pictures.
When you arrive at the hospital
Please follow the directions to the Radiology or X-ray Department and report to the main reception desk. Please note it is occasionally necessary to delay your appointment time if the scanner is required in an emergency.
Who will look after you during the scan?
A team of staff will care for you in the Radiology Department:
- Reception staff - will meet and greet you
- X-ray Assistant - will help you to prepare for your scan
- Radiographer - will perform the scan and care for you in the scan room
Preparing for the scan
It is important that you follow the preparation instructions, as this may affect whether or not your scan will be able to go ahead, and the diagnostic quality of the images acquired during your scan.
Medication
Do not take any phosphodiesterase inhibitors i.e. Viagra in the 24hrs before your scan. If you use any sprays or inhalers, please bring them with you to your appointment. You can continue to take any medication prescribed to you by your doctor as you usually would do.
Eating and drinking
In order to produce the best quality images of your heart, you must avoid caffeine 6 hours prior to the examination (tea, coffee, chocolate). These products increase your heart rate, which can lead to a poor-quality scan. We advise you to be well hydrated (drink lots of water) before your scan.
Who will be doing the examination?
Radiographers will perform the scan. If you require beta-blockers and / or glyceryl trinitrate (GTN) spray a Radiologist (a specialist Consultant in Radiology), Cardiologist (a specialist Consultant in Cardiology) or specially trained Radiographer will administer these at the beginning of the examination.
What will happen during the scan?
- You will need to book in at the CT reception desk when you first arrive for your scan. A member of staff will call you from the waiting room and take you to the changing room where you will be asked to change into a gown. You will have your blood pressure checked and electrocardiogram (ECG) stickers will be placed onto your chest so we can monitor your heart throughout the scan
- You will be taken into the CT scan room and asked to lie down on the scanner bed
- A Radiographer will then ask you a series of questions to make sure that the scan is able to go ahead. They will also place a cannula (thin plastic tube) into a vein in your arm (preferably your right arm). This is used for the administration of the beta-blockers and x-ray dye, should you require them
- If you require beta-blockers and / or GTN spray these will then be given. When all the preparation has been done, we will be ready to perform the scan
- Staff will not be able to stay with you in the scan room, but they can see and hear you at all times
- You will be asked to lie still and there will be breathing instructions for you to follow. You may be required to hold your breath for up to 15 seconds. If you struggle to hold your breath for long or find it difficult lying flat on your back, please let the Radiographers know when you arrive
- The scan will involve the injection of X-ray dye, and the scan itself will take approximately 5 minutes
If you have any comments or questions, please do not hesitate to ask the Radiographer.
Medications / drugs given during the scan
Beta-Blockers
A slower heart rate helps produce the highest quality diagnostic scan. You may have a perfectly normal heart rhythm, however, any heart rate above 65 beats per minute is considered fast for a CT scan. If this is the case, the staff may consider giving you an injection of a beta-blocker to slow your heart rate down. This is standard practice and nothing to worry about.
The beta-blocker will gently slow your heart rate, and you will be monitored and supervised by a doctor or Senior Radiographer the entire time. The beta-blocker has no major side effects and only lasts for a short period of time; approximately 20-30 minutes.
GTN Spray
The staff may feel that it is necessary for you to have a small amount of GTN spray (angina spray). The blood vessels that supply the heart muscle are very small. GTN spray helps to make the vessels bigger, so that the Doctor can see them more clearly on your scan images. It is sprayed underneath your tongue and lasts for approximately 20 minutes.
X-Ray Dye / Contrast Media
Most CT scans use “X-ray dye” or contrast media in order to visualise organs and blood vessels on the images. Without X-ray dye the quality of the scan and the information that we can get from it will be very limited and may not yield a diagnostic result.
If you have any allergies or have experienced any problems with any of these medications / drugs, please let the Radiographer know as soon as you arrive for your scan.
What happens after the scan?
- You will be asked to wait in the department for up to half an hour after the scan. In addition, you will be asked to drink increased fluids for the next 24 hours to help with rehydration
- Otherwise, once you have left the department, you can eat and drink as normal
- Continue to take your medication as you usually would, unless instructed otherwise
- You can drive home and are free to return to work / normal day life
The whole process will take approximately 90 minutes from start to finish. There may be a small delay if the department has to scan any emergencies from the Emergency Department.
When will I get the results?
The Radiologist will need to study your scans carefully to make the diagnosis. They will produce a written report of their findings, which will be sent to the doctor who referred you for the scan.
Are there any risks involved?
- The scanner uses X-rays to produce the scans. The Radiologist will consider the risk of the scan and compare it with the benefit you may get from an accurate diagnosis
- There is a small risk of an allergic reaction with the injection of dye you may be given. The Radiographer will ask you a series of medical questions before the injection is given
- If you think you may be pregnant you must tell the Radiographer
Contact information
If you have any queries regarding the examination, or suggestions on how we may improve any aspect of our service, please do not hesitate to speak to us either on the day of your examination or contact us on 01942 822368 (Monday to Friday 9am until 5pm).
Relatives and escorts
You can bring a relative or friend with you to the Radiology Department. However, they will not normally be allowed in the examination room.
Children / vulnerable adults
Please be aware that the department does not have the facilities to look after children/vulnerable adults. If you need to bring a child or vulnerable adult with you, you must bring an appropriate adult to supervise them whilst you are having the examination.
Interpreters
If you require an interpreter, please contact the department before you begin your preparation so that this can be arranged. (Please Note: Hospital policy states that relatives cannot act as interpreters).