title: Variability in the quantitation of mitral regurgitation by Doppler color flow mapping: comparison of transthoracic and transesophageal studies.
abstract: OBJECTIVE
  This study was designed to assess the most accurate and reproducible methods to quantitate mitral regurgitation by color flow transthoracic and transesophageal echocardiography.
  
  
  BACKGROUND
  Quantitative measurements of mitral regurgitant jets have resulted in an intraobserver and interobserver variability of up to 20%. Few data are available evaluating the various techniques by which mitral regurgitant jets are quantitated.
  
  
  METHODS
  Forty patients who underwent cardiac catheterization and both transesophageal and transthoracic echocardiography within 1 week were studied. Two boundaries of the color regurgitant jet area were identified and quantitated: 1) the central aliased core of the regurgitant jet with the mosaic pattern excluding any swirling low velocity flow; and 2) the largest definable area of the regurgitant flow, including low velocity flow considered to be part of the regurgitant jet.
  
  
  RESULTS
  The total regurgitant areas obtained by transthoracic and transesophageal studies did not differ (5.7 +/- 4.6 vs. 5.7 +/- 3.7 cm2; p = NS). However, the transesophageal mosaics were significantly larger than those obtained by transthoracic echocardiography (3.6 +/- 3.1 vs. 2.8 +/- 3.4 cm2; p less than 0.01). In transthoracic studies observer variability was higher when the mosaic aspect of the regurgitant jet rather than the total regurgitant area was measured (24 +/- 20 vs. 16 +/- 11%; p less than 0.05). In contrast, in transesophageal studies variability was lower when the mosaic area rather than the total regurgitant area was measured (11 +/- 12% vs. 18 +/- 18%; p less than 0.05). The best correlations with left ventriculography were obtained by using the absolute total regurgitant area (r = 0.72) for transthoracic studies and the mosaic area of the jets (r = 0.87) for transesophageal studies.
  
  
  CONCLUSIONS
  Doppler color flow jet areas correlate closely with angiographic results in the evaluation of mitral regurgitation. The total regurgitant area (including the surrounding swirling flow) in transthoracic studies and the aliased core of the regurgitant jet (mosaic) in transesophageal studies appear to be the most accurate and reproducible measurements for evaluating mitral regurgitation.
authors.affiliation: Department of Internal Medicine, Saint Louis University School of Medicine, Missouri.
authors.forename: R
authors.initials: R
authors.lastname: Castello
authors.forename: P
authors.initials: P
authors.lastname: Lenzen
authors.forename: F
authors.initials: F
authors.lastname: Aguirre
authors.forename: A
authors.initials: A
authors.lastname: Labovitz
mesh_terms: D006328:Cardiac Catheterization; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000453:epidemiology; D015588:Observer Variation