Evaluation of Myocardial Blood Flow Using 18F-flurpiridaz PET: Established Applications with Pharmacologic Stress and Roadmap for Exercise Stress Implementation.

PURPOSE OF REVIEW: Recently approved by the United States Food and Drug Administration, 18F-flurpiridaz for positron emission tomography (PET) myocardial perfusion imaging (MPI) enables high-quality assessment of myocardial blood flow (MBF). Its half-life of approximately 110 min supports regional distribution and allows unit-dose delivery. These features make this probe well suited for MBF quantitation and expand access to quantitative cardiac PET at smaller centers. RECENT FINDINGS: During pharmacologic stress, absolute MBF and myocardial flow reserve provide incremental diagnostic information beyond relative perfusion imaging. These measures have been validated across multiple methods and software platforms. Further study of this tracer under peak exercise may provide clinically relevant assessment of myocardial demand-induced changes in flow. Potential investigational approaches include artificial intelligence (AI)-derived virtual MBF, exercise-adjusted standardized uptake value (SUV) ratio-derived myocardial flow reserve (MFR) surrogate, and direct kinetic modeling during in-scanner ergometry. While conceptually promising, limitations inherent to exercise-based approaches in stress MBF and/or MFR estimation highlight the need for pragmatic research strategies before potential clinical applicability.