What is a CT Coronary Angiogram?
CT Coronary Angiography (CTCA) provides your doctor with a complete and accurate assessment of the coronary arteries of your heart. It’s the fastest, most accurate and possibly the safest non-invasive way of establishing if you have coronary artery disease and the degree of severity. Coronary artery disease is the hardening of the coronary arteries as a result of a build-up of plaque inside the artery wall (usually atherosclerosis).
The latest technology allows us to see the full expression of coronary disease unlike with other non-invasive testing modalities, where only severe narrowing can be reliably identified. As poor outcomes correlate with plaque burden and not necessarily severe narrowings, opportunities for preventing death and heart attacks are maximized going forwards (SCOTT-HEART study).
The CT utilises x-rays to create a complete 3D image of your heart and all its arteries. With the latest technologies the radiation exposure is minimized to that comparable with living in Perth for a few months (background radiation in Perth is 2.2mSv; our doses can be as low as 0.3mSv depending on body habitus and heart rate).
What will happen during the examination?
Welcome: Our receptionist will greet you and collate your information. You will then be taken to our preparation area and the staff will discuss your health history, record your blood pressure, pulse rate and perform an ECG.
Getting ready: You will be asked to lie down/ recline and an cannula will be placed in your arm to administer the ‘contrast’ agent. This highlights the arteries in your heart. Many patients will require a further dose of medication to control heart rate.
Once your heart rate is suitable, you will go into the CT suite and lay down on the scanner bed. Breathing instructions will be given. A nitroglycerin tablet may be placed under your tongue to help improve images. The imaging will then commence.
After the scan: We will take you back to the preparation area and record your blood pressure and pulse as needed for approximately 15-30 minutes. You are free to go after this period, when advised that this is safe by staff.
What is the Preparation?
When you make your appointment, our receptionist will ask a few questions and take you through some do’s and don’ts. For instance:
- Please ensure you take your usual medications as directed with a small amount of water, with the exception of diabetes medications.
- You should not have caffeine (coffee, tea, cola, energy drinks or chocolate) or smoke during the 12 hours before your appointment.
- Please do not take Viagra (or Cialis or Levitra) during the 48 hours before your appointment.
- You will be advised to fast 2 hours prior to your test. Please have a light meal before fasting. Drink approximately ½ a litre of water prior to fasting unless you have been advised to restrict fluids.
- If you are a diabetic please inform staff when you make your appointment.
It is important that you follow the above preparations as closely as possible to ensure the safety and quality of your scan.
Are there any risks?
You will receive a small dose of x-ray radiation. The benefits of detecting disease are believed to outweigh any potential risks from receiving such a small dose. However, please advise the radiographer if you are, or think you may be pregnant.
Problems related to the contrast injection are very rare. The procedural risks are less than conventional catheter angiography. The injection will be discussed prior to the examination and you will be asked to complete a questionnaire and give your consent.
Please inform us if you are taking any diabetic medication, have kidney disease or have had a previous reaction to x-ray contrast.
After the examination
After the scan we use powerful 3D computer workstations to evaluate the source data, generate images and create anatomic displays of the vessels which the Cardiologist (a specialist doctor) uses to produce the examination report.
The scan processing and reporting takes more time than other radiology procedures due to the complicated imaging required. For your convenience we can generally deliver the imaging and report to your referring doctor and general practitioner within a few days. We suggest you make an appointment with your doctor within a few days of your scan.