title: Real-time 3D transesophageal echocardiography for the evaluation of rheumatic mitral stenosis.
abstract: OBJECTIVE
  The aims of this study were: 1) to assess the feasibility and reliability of performing mitral valve area (MVA) measurements in patients with rheumatic mitral valve stenosis (RhMS) using real-time 3-dimensional transesophageal echocardiography (3DTEE) planimetry (MVA(3D)); 2) to compare MVA(3D) with conventional techniques: 2-dimensional (2D) planimetry (MVA(2D)), pressure half-time (MVA(PHT)), and continuity equation (MVA(CON)); and 3) to evaluate the degree of mitral commissural fusion.
  
  
  BACKGROUND
  3DTEE is a novel technique that provides excellent image quality of the mitral valve. Real-time 3DTEE is a relatively recent enhancement of this technique. To date, there have been no feasibility studies investigating the utility of real-time 3DTEE in the assessment of RhMS.
  
  
  METHODS
  Forty-three consecutive patients referred for echocardiographic evaluation of RhMS and suitability for percutaneous mitral valvuloplasty were assessed using 2D transthoracic echocardiography and real-time 3DTEE. MVA(3D), MVA(2D), MVA(PHT), MVA(CON), and the degree of commissural fusion were evaluated.
  
  
  RESULTS
  MVA(3D) assessment was possible in 41 patients (95%). MVA(3D) measurements were significantly lower compared with MVA(2D) (mean difference: -0.16 ± 0.22; n=25, p<0.005) and MVA(PHT) (mean difference: -0.23 ± 0.28 cm(2); n=39, p<0.0001) but marginally greater than MVA(CON) (mean difference: 0.05 ± 0.22 cm(2); n=24, p=0.82). MVA(3D) demonstrated best agreement with MVA(CON) (intraclass correlation coefficient [ICC] 0.83), followed by MVA(2D) (ICC 0.79) and MVA(PHT) (ICC 0.58). Interobserver and intraobserver agreement was excellent for MVA(3D), with ICCs of 0.93 and 0.96, respectively. Excellent commissural evaluation was possible in all patients using 3DTEE. Compared with 3DTEE, underestimation of the degree of commissural fusion using 2D transthoracic echocardiography was observed in 19%, with weak agreement between methods (κ<0.4).
  
  
  CONCLUSIONS
  MVA planimetry is feasible in the majority of patients with RhMS using 3DTEE, with excellent reproducibility, and compares favorably with established methods. Three-dimensional transesophageal echocardiography allows excellent assessment of commissural fusion.
authors.affiliation: Department of Cardiology, Prince of Wales Hospital, Sydney, Australia. dschlo1038@aol.com
authors.forename: Dominik
authors.initials: D
authors.lastname: Schlosshan
authors.forename: Gunjan
authors.initials: G
authors.lastname: Aggarwal
authors.forename: Gita
authors.initials: G
authors.lastname: Mathur
authors.forename: Roger
authors.initials: R
authors.lastname: Allan
authors.forename: Greg
authors.initials: G
authors.lastname: Cranney
mesh_terms: D000368:Aged; D002404:Catheterization; D019560:Echocardiography, Three-Dimensional; D017548:Echocardiography, Transesophageal; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008946:Mitral Valve Stenosis / Q000000981:diagnostic imaging* / Q000628:therapy; D009517:New South Wales; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012214:Rheumatic Heart Disease / Q000000981:diagnostic imaging* / Q000628:therapy