What a CT coronary angiogram shows
A CTCA is a CT scan of the heart taken after an injection of contrast dye into a vein in the arm. The dye fills the coronary arteries so the scanner can show whether there is plaque in the artery wall and whether any narrowing is severe enough to need treatment. It is the test most often used to work out whether chest pain is coming from the coronary arteries, and it can also give a coronary calcium score.
Unlike an invasive angiogram, nothing goes into the artery itself. Most patients are at the imaging centre for two to two and a half hours and go home the same day.
Who it is for
- People with chest pain or breathlessness on exertion where the cause is uncertain
- People with risk factors such as high cholesterol, diabetes, high blood pressure or a family history of early heart disease, where knowing whether plaque is present changes treatment
- Assessment before some non-cardiac operations, and follow-up of stents or bypass grafts in selected patients
CTCA is less suitable for people with very irregular heart rhythms, severe kidney impairment or a previous serious contrast reaction. A/Prof Verjans will discuss whether another test, such as a stress echocardiogram, would suit you better.
Where the scan is done
A/Prof Verjans refers CTCA to Jones Radiology at SAHMRI on North Terrace, where the scan is performed on a photon-counting CT scanner. Photon-counting detectors give sharper images of small vessels, stents and calcified plaque at a lower radiation dose than conventional CT. Bookings with Jones Radiology at SAHMRI: (08) 8407 6750.
How to prepare
- No fasting is needed; water and clear fluids are encouraged.
- Do not smoke or vape for four hours before the scan, and avoid caffeine on the day unless told otherwise.
- Keep taking beta blockers and other regular medicines as prescribed.
- Do not take sildenafil (Viagra) or tadalafil (Cialis) for three days beforehand, if your prescribing doctor agrees, because they cannot be combined with the GTN spray used during the scan.
- Tell the radiology team about kidney problems, diabetes medicines, asthma, previous contrast reactions or pregnancy.
On the day
Nurses check your heart rate and blood pressure and may give you a tablet to slow the heart, which takes about an hour to work. A cannula is placed in a vein. In the scanner you lie on your back with your arms raised, a GTN spray is given under the tongue to widen the arteries, and you hold your breath for a few seconds while the images are taken. Afterwards you are observed for about 30 minutes before the cannula is removed.
Results and follow-up
The radiologist's report is sent to A/Prof Verjans, usually within a few working days. He reviews the images and report with you at a follow-up appointment, explains what any plaque means for you, and agrees a plan, which may include medication, lifestyle changes, further tests or, less commonly, an invasive angiogram. Your GP receives a copy of the letter, and you can see it in the Patient Hub.
Cost and Medicare
A Medicare rebate applies when the scan meets Medicare criteria and is requested by a specialist. Jones Radiology confirms any out-of-pocket fee at the time of booking. If cost is a concern, please tell us before the scan is booked.