Exercise (18)FDG imaging for the detection of CAD: What are the clinical hurdles?

Myocardial perfusion imaging (MPI) has been in clinical use for over 30 years, providing an effective, reliable, and relatively simple tool for diagnosis, risk stratification, and follow-up of patients with suspected or know coronary artery disease (CAD). The unique strength of nuclear imaging is its ability to provide tools for imaging biochemical and metabolic processes, and receptor and transporter functions at molecular and cellular levels in intact organisms under various physiologic conditions. Metabolic imaging using radiolabeled glucose analogues ((18)F-fluorodeoxyglucose [(18)FDG]) provides a unique ability to image myocardial ischemia directly ("hot spot" imaging) in patients with known or suspected CAD. Exercise (18)FDG imaging can potentially overcome some of the limitations of currently used stress-rest MPI. In this article, we describe recent studies using exercise (18)FDG for imaging myocardial ischemia and its potential use in routine clinical practice.