Emerging PET Radiotracer May Improve Detection of Coronary Artery Disease in Obese Patients

The use of conventional imaging for diagnosing coronary artery disease (CAD) in obese patients can be challenging. Attenuation artifacts can be problematic with single photon emission computed tomography (SPECT) and a lack of crisp image quality is an issue with coronary computed tomography angiography (CCTA) in this patient population, pointed out Krishna Patel, MD, in an interview at the recent Society for Nuclear Medicine and Molecular Imaging (SNMMI) conference.

Higher radiation dosing is also a concern with both of the aforementioned modalities, noted Dr. Patel, an assistant professor of medicine (cardiology) and population health science and policy at Icahn School of Medicine at Mount Sinai.

Accordingly, Dr. Patel and colleagues examined the use of the positron emission tomography (PET) perfusion radiotracer agent ¹⁸F-flurpiridaz in comparison to ^99mTc-SPECT for detecting CAD in a subgroup analysis involving 298 obese patients (mean age of 62.1) from a phase 3 trial.

The researchers found that among obese patients, ¹⁸F-flurpiridaz demonstrated higher sensitivity rates (76.9 percent versus 69.2 percent) and specificity rates (66.9 percent versus 61.9 percent) in comparison to ^99mTc-SPECT. The use of ¹⁸F-flurpiridaz also reduced radiation exposure by one-third (6.2 mSv PET) in comparison to tetrofosmin SPECT (9.9 mSv) and by one-half in comparison to sestamibi SPECT (12.4 mSv), according to Dr. Patel and colleagues.

Dr. Patel, the director of cardiac PET at Mount Sinai Morningside in New York City, added that other key benefits of ¹⁸F-flurpiridaz include a longer half-life (110 minutes) than other PET perfusion tracer agents and unit dose availability, factors that may significantly expand access to stress cardiac PET myocardial perfusion imaging.

For more insights from Dr. Patel, watch the video below.