Cardiac imaging
A radioactive tracer injected into the bloodstream lights up on a scanner wherever the heart muscle is getting enough blood flow, so doctors can see blocked arteries without surgery.
Overview
Nuclear cardiology's long-standing tools are SPECT myocardial perfusion imaging with technetium-99m agents, and PET perfusion imaging with 82Rb, 13N-ammonia or 15O-water, the last two requiring an on-site cyclotron or generator that limits which centres can offer PET perfusion at all. The field's biggest recent development is the FDA approval, on 27 September 2024, of flurpiridaz F-18 (Flyrcado, GE HealthCare/Lantheus) for PET myocardial perfusion imaging under rest or stress (pharmacologic or exercise) in adults with known or suspected coronary artery disease — the first new perfusion radiopharmaceutical approved by the FDA in nearly 30 years, based on the phase 3 AURORA trial and prior studies.
Flurpiridaz's practical advantage is that, unlike 82Rb or 13N-ammonia, its 110-minute fluorine-18 half-life allows it to be manufactured centrally at a regional cyclotron and shipped as a unit dose to hospitals that have no cyclotron or generator of their own, which nuclear cardiology commentary expects to expand access to PET perfusion imaging considerably. It also allows quantification of absolute myocardial blood flow and myocardial flow reserve, similar to 13N-ammonia and 82Rb.
What is still unresolved: the FDA approval of flurpiridaz explicitly does not change existing PET myocardial perfusion imaging appropriate-use criteria, so its clinical positioning relative to SPECT and to the older PET perfusion tracers is still being worked out in practice, and real-world access will depend on how widely regional cyclotron-supplied unit doses actually reach community hospitals rather than only academic centres with existing PET infrastructure.
Notes
top- FDA approval of flurpiridaz F-18 (Flyrcado, 27 September 2024) explicitly does not change existing PET myocardial perfusion appropriate-use criteria; its place in the diagnostic pathway relative to SPECT and older PET tracers is still being worked out.
- Flurpiridaz's 110-minute half-life allows central cyclotron manufacture and unit-dose shipping, unlike 82Rb (generator-based) or 13N-ammonia (needs an on-site cyclotron); whether this actually expands access to community hospitals in practice is not yet demonstrated at scale.