Evaluation of the Novel Myocardial Perfusion Positron-Emission Tomography Tracer

Background—Positron-emission tomography (PET) tracers for myocardial perfusion are commonly labeled with short-lived isotopes that limit their widespread clinical use. F-BMS-747158-02 (F-BMS) is a novel pyridaben derivative that was evaluated for assessment of myocardial perfusion by comparison with N-ammonia (NH3) and with radioactive microspheres in a pig model. Methods and Results—Fourteen pigs injected with 500 MBq of NH3 or 100 to 200 MBq of F-BMS underwent dynamic PET at rest and during pharmacological stress. In 8 of these pigs, F-BMS was injected during stress combined with transient, 2.5-minute constriction of the left anterior descending coronary artery. Radioactive microspheres were coinjected with F-BMS. Ratios of myocardial tracer uptake to surrounding tissues were determined, and myocardial blood flow was quantified by compartmental modeling. Both tracers showed high and homogeneous myocardial uptake. Compared with NH3, F-BMS showed higher activity ratios between myocardium and blood (rest 2.5 versus 4.1; stress 2.1 versus 5.8), liver (rest 1.2 versus 1.8; stress 0.7 versus 2.0), and lungs (rest 2.5 versus 4.2; stress 2.9 versus 6.4). Regional myocardial blood flow assessed with F-BMS PET showed good correlation (r 0.88, slope 0.84) and agreement (mean difference 0.10 [25th percentile 0.3, 75th percentile 0.1 mL · min 1 · g ]) with that measured with radioactive microspheres over a flow range from 0.1 to 3.0 mL · min 1 · g . The extent of defects induced by left anterior descending coronary artery constriction measured by F-BMS and microspheres also correlated closely (r 0.63, slope 1.1). Conclusions—F-BMS-747158-02 is a very attractive new PET perfusion tracer that allows quantitative assessment of regional myocardial perfusion over a wide flow range. The long half-life of F renders this tracer useful for clinical PET/CT applications in the workup of patients with suspected or proven coronary artery disease. (Circulation. 2009; 119:2333-2342.)