title: Non-invasive assessment of the haemodynamic significance of coronary stenosis using fusion of cardiac computed tomography and 3D echocardiography.
abstract: OBJECTIVE
  Abnormal computed tomography coronary angiography (CTCA) often leads to stress testing to determine haemodynamic significance of stenosis. We hypothesized that instead, this could be achieved by fusion imaging of the coronary anatomy with 3D echocardiography (3DE)-derived resting myocardial deformation.
  
  
  RESULTS
  We developed fusion software that creates combined 3D displays of the coronary arteries with colour maps of longitudinal strain and tested it in 28 patients with chest pain, referred for CTCA (256 Philips scanner) who underwent 3DE (Philips iE33) and regadenoson stress CT. To obtain a reference for stenosis significance, coronaries were also fused with colour maps of stress myocardial perfusion. 3D displays were used to detect stress perfusion defect (SPD) and/or resting strain abnormality (RSA) in each territory. CTCA showed 56 normal arteries, stenosis <50% in 17, and >50% in 8 arteries. Of the 81 coronary territories, SPDs were noted in 20 and RSAs in 29. Of the 59 arteries with no stenosis >50% and no SPDs, considered as normal, 12 (20%) had RSAs. Conversely, with stenosis >50% and SPDs (haemodynamically significant), RSAs were considerably more frequent (5/6 = 83%). Overall, resting strain and stress perfusion findings were concordant in 64/81 arteries (79% agreement).
  
  
  CONCLUSIONS
  Fusion of CTCA and 3DE-derived data allows direct visualization of each coronary artery and strain in its territory. In this feasibility study, resting strain showed good agreement with stress perfusion, indicating that it may be potentially used to assess haemodynamic impact of coronary stenosis, as an alternative to stress testing that entails additional radiation exposure.
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Francesco
authors.initials: F
authors.lastname: Maffessanti
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Amit R
authors.initials: AR
authors.lastname: Patel
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Mita B
authors.initials: MB
authors.lastname: Patel
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Walter
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Anuj
authors.initials: A
authors.lastname: Mediratta
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Diego
authors.initials: D
authors.lastname: Medvedofsky
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.|Laboratoire d'Imagerie Biomédicale, Sorbonne Universités, UPMC University Paris 06, CNRS 7371, INSERM 1146, F-75013, Paris, France.
authors.forename: Nadjia
authors.initials: N
authors.lastname: Kachenoura
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Lang
authors.affiliation: University of Chicago Medical Center, Chicago, IL, USA.
authors.forename: Victor
authors.initials: V
authors.lastname: Mor-Avi
mesh_terms: D002637:Chest Pain / Q000175:diagnosis / Q000209:etiology; D015331:Cohort Studies; D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D004636:Emergency Service, Hospital; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity
keywords: 3D echocardiography; Cardiovascular CT; Fusion imaging; Myocardial strain; Myocardium perfusion; Vasodilator stress