New research suggests that using PET CT scans to detect fatty plaques in the coronary arteries could be used to identify people at high risk of a heart attack – even though they might feel perfectly well. A study just published by researchers at the University of Edinburgh describes a hybrid heart scan technique that involves using radioactive tracers and CT scanning.
Members of the Cardiology specialty at The Physicians' Clinic got together recently to discuss what this might mean for people at risk of a heart attack and how it might change the way heart specialists practice medicine in the future.
What is PET/CT scanning?
A CT scan produces high resolution X-ray pictures are taken of the body in slices and then put together again to give a 3D image. It is quite good at visualising soft tissues such as the heart, but not brilliant. Giving a small dose of radioactivity into the blood and then taking the scan minutes later means that pictures show exactly where the radioactivity (which shows up very well on the CT scan) ends up.
How might a PET/CT heart scan detect people at risk?
In the study, a small number of patients who had recently had a heart attack were given PET/CT scans. These showed the area of the coronary arteries that had the dangerous fatty plaques and in 37 cases, pinpointed the exact plaque that had ruptured and caused the heart attack.
The challenge now will be to find out if PET/CT heart scans can identify fatty plaques that are about to rupture and cause trouble. This is not a tried and tested technique in cardiology, but it could be worth more tests.
What do our cardiologists think?
Dr Amanda Varnava thinks that "the technique could be very useful, particularly for detecting 'vulnerable plaques' (caused by cholesterol build up) that are prone to causing future heart attacks but are currently not detected by conventional tests."
“Identification of vulnerable plaques in the coronary arteries that may lead to myocardial infarction i.e. a means of predicting heart attacks, has been the holy grail for interventional cardiologists for some time.” notes Dr Christopher Baker.
All four of our cardiologists are in agreement that much more research is now required.
“For years now, it has been a great challenge to work out how to use imaging technology to scan arteries in a moving organ such as the beating heart. This exciting new research suggests this hurdle can be overcome.”