Established and Emerging Fluorine-18-Labeled Cardiac PET Radiotracers

Positron emission tomography (PET)/computed tomography is a major imaging strategy for cardiovascular disease characterization. Whereas multiple radioisotopes can be used for PET imaging of cardiac disease processes, fluorine-18 (¹⁸F) presents key advantages. These include availability as a unit dose given a favorable half-life of 109.7 minutes and a short positron range leading to a high spatial resolution. In this context, there is growing interest in the development of novel ¹⁸F-labeled probes applied to cardiac PET imaging, which in turn provide clinicians with new methods to evaluate disease pathways of interest. Beyond ¹⁸F-fluorodeoxyglucose, used in routine clinical practice to scrutinize myocardial viability, cardiac sarcoidosis, as well as prosthetic valve and cardiac device infection, new ¹⁸F-labeled radiopharmaceuticals have undergone clinical evaluation. These include ¹⁸F-flurpiridaz, which was recently approved by the U.S. Food and Drug Administration for myocardial perfusion imaging and that is also amenable to accurate myocardial blood flow quantitation, ¹⁸F-sodium fluoride to detect metabolically active epicardial coronary atherosclerotic lesions, and the ¹⁸F-labeled amyloid radiotracers florbetapir, flutemetamol, and florbetaben. This review will further explore emerging ¹⁸F-labeled probes applied to cardiac sarcoidosis, myocardial innervation, and ongoing fibrosis/fibroblast activation.