Adding CFR improves diagnostic accuracy of 13N-ammonia PET MPI to detect CAD

86 Objectives Quantitative measurement of flow and coronary flow reserve (CFR) has been perceived as an important advantage of PET over SPECT MPI. We analyzed the added diagnostic value of CFR over PET MPI alone as assessed with 13N-ammonia and PET/CT to predict angiographic coronary artery disease (CAD). Methods Seventy-three patients underwent one-day adenosine-stress/rest 13N-ammonia PET/CT MPI and global CFR was calculated. The added value of CFR as an adjunct to MPI for predicting CAD (luminal narrowing ≥50%) was evaluated using invasive coronary angiography as a standard of reference. Results Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of MPI for detecting significant CAD was 79%, 80%, 91%, 59%, and 79%, respectively. Adding the cut-off for global CFR Conclusions The quantification of the global CFR in 13N-ammonia PET/CT MPI provides a substantial added value in diagnosing CAD. Particularly in patients with normal MPI it helps to unmask clinically significant CAD. Research Support The study was supported by grants from the Swiss National Science Foundation (SNSF) to PAK and to MF