title: Quantitative assessment of severity of ventricular septal defect by three-dimensional reconstruction of color Doppler-imaged vena contracta and flow convergence region.
abstract: BACKGROUND
  The aim of the present study was to investigate the feasibility and potential value of the computer-controlled, 3D, echocardiographic reconstruction of the color Doppler-imaged vena contracta (CDVC) and the flow convergence (FC) region as a means of accurately and quantitatively estimating the severity of a ventricular septal defect (VSD).
  
  
  RESULTS
  We performed a 3D reconstruction of the CDVC and the FC region in 19 patients with an isolated VSD using an ultrasound system interfaced with a Tomtec computer. The variable asymmetric geometry of the CDVC and the FC region could be 3D-visualized in all patients. The 3D-measured areas of CDVC correlated well with volumetric measurements of the severity of VSD (r=0.97, P:<0.001). Regression analysis between the shunt flow rate (calculated from the product of the area of CDVC and the continuous Doppler-derived velocity time integral) and the corresponding reference results (calculated by cardiac catheterization) demonstrated a close correlation (r=0.95, P:<0.001). There was also a good correlation between shunt flow rates calculated using the conventional 2D, 1-axis measurement of the FC isovelocity surface area with the hemispheric assumption (r=0.95, P:<0.001); shunt flow rates calculated using 3D, 3-axis measurements of the FC region (r=0.97, P:<0.01); and reference results by cardiac catheterization. However, the 2D method substantially underestimated the actual shunt flow rate.
  
  
  CONCLUSIONS
  The 3D reconstruction of the CDVC and the FC region may aid in quantifying the severity of VSD.
authors.affiliation: Department of Pediatrics and the Cardiovascular Research Institute, Kurume University School of Medicine, Kurume, Japan. masaishi@med.kurume-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Ishii
authors.forename: K
authors.initials: K
authors.lastname: Hashino
authors.forename: G
authors.initials: G
authors.lastname: Eto
authors.forename: T
authors.initials: T
authors.lastname: Tsutsumi
authors.forename: W
authors.initials: W
authors.lastname: Himeno
authors.forename: Y
authors.initials: Y
authors.lastname: Sugahara
authors.forename: H
authors.initials: H
authors.lastname: Muta
authors.forename: J
authors.initials: J
authors.lastname: Furui
authors.forename: T
authors.initials: T
authors.lastname: Akagi
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: H
authors.initials: H
authors.lastname: Kato
mesh_terms: D002648:Child; D002675:Child, Preschool; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D019560:Echocardiography, Three-Dimensional; D005240:Feasibility Studies; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D011446:Prospective Studies; D012039:Regional Blood Flow; D012720:Severity of Illness Index