title: Three-dimensional color Doppler echocardiographic quantification of tricuspid regurgitation orifice area: comparison with conventional two-dimensional measures.
abstract: BACKGROUND
  Three-dimensional (3D) color Doppler echocardiography (CDE) provides directly measured vena contracta area (VCA). However, a large comprehensive 3D color Doppler echocardiographic study with sufficiently severe tricuspid regurgitation (TR) to verify its value in determining TR severity in comparison with conventional quantitative and semiquantitative two-dimensional (2D) parameters has not been previously conducted. The aim of this study was to examine the utility and feasibility of directly measured VCA by 3D transthoracic CDE, its correlation with 2D echocardiographic measurements of TR, and its ability to determine severe TR.
  
  
  METHODS
  Ninety-two patients with mild or greater TR prospectively underwent 2D and 3D transthoracic echocardiography. Two-dimensional evaluation of TR severity included the ratio of jet area to right atrial area, vena contracta width, and quantification of effective regurgitant orifice area using the flow convergence method. Full-volume breath-hold 3D color data sets of TR were obtained using a real-time 3D echocardiography system. VCA was directly measured by 3D-guided direct planimetry of the color jet. Subgroup analysis included the presence of a pacemaker, eccentricity of the TR jet, ellipticity of the orifice shape, underlying TR mechanism, and baseline rhythm.
  
  
  RESULTS
  Three-dimensional VCA correlated well with effective regurgitant orifice area (r = 0.62, P < .0001), moderately with vena contracta width (r = 0.42, P < .0001), and weakly with jet area/right atrial area ratio. Subgroup analysis comparing 3D VCA with 2D effective regurgitant orifice area demonstrated excellent correlation for organic TR (r = 0.86, P < .0001), regular rhythm (r = 0.78, P < .0001), and circular orifice (r = 0.72, P < .0001) but poor correlation in atrial fibrillation rhythm (r = 0.23, P = .0033). Receiver operating characteristic curve analysis for 3D VCA demonstrated good accuracy for severe TR determination.
  
  
  CONCLUSIONS
  Three-dimensional VCA measurement is feasible and obtainable in the majority of patients with mild or greater TR. Three-dimensional VCA measurement is also feasible in patients with atrial fibrillation but performed poorly even with <20% cycle length variation. Three-dimensional VCA has good cutoff accuracy in determining severe TR. This simple, straightforward 3D color Doppler measurement shows promise as an alternative for the quantification of TR.
authors.affiliation: Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota; Division of Cardiology, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan; Medical College, China Medical University, Taichung, Taiwan.
authors.forename: Tien-En
authors.initials: TE
authors.lastname: Chen
authors.affiliation: Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota.
authors.forename: Susan H
authors.initials: SH
authors.lastname: Kwon
authors.affiliation: Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota.
authors.forename: Maurice
authors.initials: M
authors.lastname: Enriquez-Sarano
authors.affiliation: Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota.
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Wong
authors.affiliation: Division of Cardiovascular Disease, Mayo Clinic, Rochester, Minnesota. Electronic address: mankad.sunil@mayo.edu.
authors.forename: Sunil V
authors.initials: SV
authors.lastname: Mankad
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012680:Sensitivity and Specificity; D014261:Tricuspid Valve / Q000000981:diagnostic imaging; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology
keywords: 2D; 3D; AF; Atrial fibrillation; CDE; Color Doppler echocardiography; EROA; Effective regurgitant orifice area; JA; Jet area; MPR; MR; Mitral regurgitation; Multiplanar reconstruction; PISA; Proximal isovelocity surface area; RAA; ROC; RV; Receiver operating characteristic; Right atrial area; Right ventricular; TR; TV; Three-dimensional; Three-dimensional color Doppler echocardiography; Tricuspid regurgitation; Tricuspid valve; Two-dimensional; VCA; VCW; Valvular heart disease; Vena contracta area; Vena contracta width