title: Diagnostic value of 13N-ammonia myocardial perfusion PET: added value of myocardial flow reserve.
abstract: The ability to obtain quantitative values of flow and myocardial flow reserve (MFR) has been perceived as an important advantage of PET over conventional nuclear myocardial perfusion imaging (MPI). We evaluated the added diagnostic value of MFR over MPI alone as assessed with (13)N-ammonia and PET/CT to predict angiographic coronary artery disease (CAD).
  
  
  METHODS
  Seventy-three patients underwent 1-d adenosine stress-rest (13)N-ammonia PET/CT MPI, and MFR was calculated. The added value of MFR as an adjunct to MPI for predicting CAD (luminal narrowing ≥ 50%) was evaluated using invasive coronary angiography as a standard of reference.
  
  
  RESULTS
  Per patient, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MPI for detecting significant CAD were 79%, 80%, 91%, 59%, and 79%, respectively. Adding a cutoff of less than 2.0 for global MFR to MPI findings improved the values to 96% (P < 0.005), 80%, 93%, 89% (P < 0.005), and 92% (P < 0.005), respectively.
  
  
  CONCLUSIONS
  The quantification of MFR in (13)N-ammonia PET/CT MPI provides a substantial added diagnostic value for detection of CAD. Particularly in patients with normal MPI results, quantification of MFR helps to unmask clinically significant CAD.
authors: Cardiac Imaging, Department of Radiology, University Hospital Zurich, Zurich, Switzerland.
authors: Michael
authors: M
authors: Fiechter
authors: Jelena R
authors: JR
authors: Ghadri
authors: Cathérine
authors: C
authors: Gebhard
authors: Tobias A
authors: TA
authors: Fuchs
authors: Aju P
authors: AP
authors: Pazhenkottil
authors: Rene N
authors: RN
authors: Nkoulou
authors: Bernhard A
authors: BA
authors: Herzog
authors: Christophe A
authors: CA
authors: Wyss
authors: Oliver
authors: O
authors: Gaemperli
authors: Philipp A
authors: PA
authors: Kaufmann
mesh_terms: D000641:Ammonia; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging; D009590:Nitrogen Radioisotopes; D049268:Positron-Emission Tomography; D012189:Retrospective Studies
chemical_list: D009590:Nitrogen Radioisotopes; D000641:Ammonia