PET scans back on cardiologists’ radars

As Positron Emission Tomography (PET) scanning technology becomes more accessible, it could change the way doctors assess cardiovascular disease in patients, according to new research.

PET scanning is a method where patients are injected with non-toxic amounts of a radioactive isotope. These are known as “tracer” dyes that show up in the images that the scanner camera takes of patients’ bodies.

PET scans could offer more detailed images of blood flow and  heart contractions and measure certain neurohormonal regulators that could cause heart failure, according to “Current and Future Clinical Applications of Cardiac Positron Emission Tomography.” The review released March 20 includes research conducted at the University of Ottawa Heart Institute.

Ottawa is a bit of an anomaly in Canada with a relativelylarge number of PET scanners — two at the Ottawa Heart Research Institute and one at the Ottawa General for cancer assessment.

PET scans were too expensive and tracers were too difficult to come by, until now, said co-author Robert deKemp who is head imaging physician in cardiac imaging at  theHeart Institute.

Most hospitals and research institutes are equipped with single-photon emission tomography (SPECT) scanners. The more sensitive PET scanners are “very similar but a technological advancement,” deKemp said.

Unlike SPECT scanners, PET scans give a more detailed image, he said. The scanners are also useful in performing scans  on obese patients whose “girth” in their lower body area might otherwise obstruct the imaging, he added.

PET scans have become a more viable option over the years as the costs of tracers decreased from $600 per treatment to about $200-300.

These costs have gone down as the tracers are in higher demand for cancer assessment.

“Our hope is that the use of positron emission tomography grows for cardiac imaging,” just as it has with cancer scanning, he said.

But first, deKemp said, “what needs to happen is for the cost of PET scanners to go down.”

PET scanners cost between $500,000 and $1 million while a SPECT scanner costs about half of that.