title: Novel Approach to Three-Dimensional Echocardiographic Quantification of Right Ventricular Volumes and Function from Focused Views.
abstract: BACKGROUND
  Echocardiographic assessment of the right ventricle is difficult because of its complex shape. Three-dimensional echocardiographic (3DE) imaging allows more accurate and reproducible analysis of the right ventricle than two-dimensional methodology. However, three-dimensional volumetric analysis has been hampered by difficulties obtaining consistently high-quality coronal views, required by the existing software packages. The aim of this study was to test a new approach for volumetric analysis without coronal views by using instead right ventricle-focused three-dimensional acquisition with multiple short-axis views extracted from the same data set.
  
  
  METHODS
  Transthoracic 3DE and cardiovascular magnetic resonance (CMR) images were prospectively obtained on the same day in 147 patients with wide ranges of right ventricular (RV) size and function. RV volumes and ejection fraction were measured from 3DE images using the new software and compared with CMR reference values. Comparisons included linear regression and Bland-Altman analyses. Repeated measurements were performed to assess measurement variability.
  
  
  RESULTS
  Sixteen patients were excluded because of suboptimal image quality (89% feasibility). RV volumes and ejection fraction obtained with the new 3DE technique were in good agreement with CMR (end-diastolic volume, r = 0.95; end-systolic volume, r = 0.96; ejection fraction, r = 0.83). Biases were, respectively, -6 ± 11%, 0 ± 15%, and -7 ± 17% of the mean measured values. In a subset of patients with suboptimal 3DE images, the new analysis resulted in significantly improved accuracy against CMR and reproducibility, compared with previously used coronal view-based techniques. The time required for the 3DE analysis was approximately 4 min.
  
  
  CONCLUSIONS
  The new software is fast, reproducible, and accurate compared with CMR over a wide range of RV size and function. Because right ventricle-focused 3DE acquisition is feasible in most patients, this approach may be applicable to a broader population of patients who can benefit from RV volumetric assessment.
authors.affiliation: Department of Medicine, University of Chicago Medical Center, Chicago, Illinois.
authors.forename: Diego
authors.initials: D
authors.lastname: Medvedofsky
authors.affiliation: Department of Medicine, University of Chicago Medical Center, Chicago, Illinois.
authors.forename: Karima
authors.initials: K
authors.lastname: Addetia
authors.affiliation: Department of Medicine, University of Chicago Medical Center, Chicago, Illinois.
authors.forename: Amit R
authors.initials: AR
authors.lastname: Patel
authors.affiliation: TomTec, Unterschleissheim, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Sedlmeier
authors.affiliation: TomTec, Unterschleissheim, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Baumann
authors.affiliation: Department of Medicine, University of Chicago Medical Center, Chicago, Illinois.
authors.forename: Victor
authors.initials: V
authors.lastname: Mor-Avi
authors.affiliation: Department of Medicine, University of Chicago Medical Center, Chicago, Illinois. Electronic address: rlang@medicine.bsd.uchicago.edu.
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Lang
mesh_terms: D015331:Cohort Studies; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005069:Evaluation Studies as Topic; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000502:physiology*; D016278:Ventricular Function, Right / Q000502:physiology
keywords: Right ventricle; Right ventricular volumes and function; Three-dimensional echocardiography