title: Rapid cardiac hybrid imaging with minimized radiation dose for accurate non-invasive assessment of ischemic coronary artery disease.
abstract: BACKGROUND
  Ischemic coronary artery disease (CAD) is a major cause for morbidity and mortality resulting in a continuously increasing number of diagnostic interventions. We have validated a new hybrid imaging method using minimized radiation dose for rapid non-invasive prediction of invasive coronary angiography (CA) findings with regard to coronary lesion detection and revascularization.
  
  
  METHODS
  Forty patients referred for elective invasive coronary angiography (CA) due to suspected CAD were prospectively enrolled to undergo a low-dose CTCA with prospective ECG-triggering and a stress-only SPECT-MPI scan administering half of the standard low-dose stress (99m)Tc-tetrofosmin activity. The latter was acquired immediately after adenosine stress (omitting the standard 30-60 min waiting time). After fusing CTCA and SPECT-MPI decisions towards conservative management versus revascularization strategy based on hybrid images were compared to the decisions taken by the interventional operator in the catheterization laboratory based on CA. The latter served as standard of reference.
  
  
  RESULTS
  Hybrid images yielded sensitivity, specificity, positive and negative predictive values and accuracy of 100%, 96.0%, 100%, 93.8% and 97.5% for predicting coronary revascularization. The estimated mean effective radiation doses were significantly lower for hybrid imaging (4.7 ± 1.0 mSv) than for invasive CA (8.7 ± 4.2 mSv; P<0.001 vs. hybrid). Total non-invasive protocol time was below 60 min, comparing favourably to standard SPECT protocols.
  
  
  CONCLUSIONS
  Rapid cardiac hybrid imaging allows accurate prediction of invasive CA findings and of treatment decision despite minimized radiation dose and protocol time.
authors.affiliation: Cardiac Imaging, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Bernhard A
authors.initials: BA
authors.lastname: Herzog
authors.forename: Lars
authors.initials: L
authors.lastname: Husmann
authors.forename: Ronny R
authors.initials: RR
authors.lastname: Buechel
authors.forename: Aju P
authors.initials: AP
authors.lastname: Pazhenkottil
authors.forename: Irene A
authors.initials: IA
authors.lastname: Burger
authors.forename: Ines
authors.initials: I
authors.lastname: Valenta
authors.forename: Ulrich
authors.initials: U
authors.lastname: Altorfer
authors.forename: Mathias
authors.initials: M
authors.lastname: Wolfrum
authors.forename: Rene N
authors.initials: RN
authors.lastname: Nkoulou
authors.forename: Jelena R
authors.initials: JR
authors.lastname: Ghadri
authors.forename: Christophe A
authors.initials: CA
authors.lastname: Wyss
authors.forename: Philipp A
authors.initials: PA
authors.lastname: Kaufmann
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D011829:Radiation Dosage; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*