This feasibility study evaluated the role of spectral photon-counting CT (SPCCT) compared with dual-energy CT (DECT) for myocardial perfusion imaging (MPI) at rest in patients with hemodynamically significant coronary stenosis.
Eighteen very high-risk patients underwent both imaging techniques within three days, and the findings were compared with invasive coronary angiography and fractional flow reserve as reference standards.
Overall, SPCCT achieved diagnostic accuracy comparable to DECT (accuracy 76.9% vs. 74.4%) in identifying myocardial hypoperfusion but showed superior performance in the left anterior descending artery territory (90% vs. 60%). Both modalities detected significant attenuation differences between normal and hypoperfused myocardial segments, though SPCCT provided greater image uniformity and higher interobserver agreement (κ = 0.86 vs. 0.62).
In conclusion, SPCCT demonstrated reliable diagnostic accuracy and improved reproducibility compared with DECT for resting MPI, suggesting its potential value for myocardial perfusion assessment in very high-risk coronary patients.