title: Main pulmonary artery diameter from attenuation correction CT scans in cardiac SPECT accurately predicts pulmonary hypertension.
abstract: OBJECTIVE
  To establish the value of the main pulmonary artery (MPA) diameter assessed from unenhanced computer tomography (CT) scans used for attenuation correction (AC) of single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) to predict pulmonary hypertension (PHT).
  
  
  BACKGROUND
  In contrast-enhanced chest CT scans an MPA diameter of 29 mm or greater is an established predictor of PHT. However, it is unknown, whether measurements from an unenhanced CT scan for AC may be used as predictor of PHT.
  
  
  METHODS
  100 patients underwent SPECT MPI for assessment of coronary artery disease. PHT was defined as a right ventriculo-atrial gradient of 30 mm Hg or greater by Doppler echocardiography. We compared MPA diameter from CT to SPECT findings (right ventricular hypertrophy/enlargement, septal wall motion abnormality/perfusion defect, and D-shape) to determine the best predictor of PHT.
  
  
  RESULTS
  PHT was found in 37 patients. An MPA diameter of 30 mm or greater yielded a sensitivity, specificity, accuracy, positive, and negative predictive value of 78%, 91%, 86%, 83%, and 88%, respectively. This yielded an area under the ROC curve of 0.85.
  
  
  CONCLUSIONS
  MPA diameter from low-dose unenhanced multi-slice CT reliably predicts PHT, providing an important added clinical value from AC for SPECT MPI.
authors.affiliation: Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland. irene.burger@usz.ch
authors.forename: Irene A
authors.initials: IA
authors.lastname: Burger
authors.forename: Lars
authors.initials: L
authors.lastname: Husmann
authors.forename: Bernhard A
authors.initials: BA
authors.lastname: Herzog
authors.forename: Ronny R
authors.initials: RR
authors.lastname: Buechel
authors.forename: Aju P
authors.initials: AP
authors.lastname: Pazhenkottil
authors.forename: Jelena R
authors.initials: JR
authors.lastname: Ghadri
authors.forename: Rene N
authors.initials: RN
authors.lastname: Nkoulou
authors.forename: Rolf
authors.initials: R
authors.lastname: Jenni
authors.forename: Erich W
authors.initials: EW
authors.lastname: Russi
authors.forename: Philipp A
authors.initials: PA
authors.lastname: Kaufmann
mesh_terms: D000368:Aged; D019540:Area Under Curve; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*