Evaluation of the novel myocardial perfusion positron-emission tomography tracer 18F-BMS-747158-02: Comparison to 13N-ammonia and validation with microspheres in a pig model

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 • g]) with that measured with radioactive microspheres over a flow range from 0.1 to 3.0 mL • min • 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.