title: Hemodynamic significance of mitral stenosis: use of a simple, novel index by 2-dimensional echocardiography.
abstract: OBJECTIVE
  We sought to assess the hemodynamic significance of mitral stenosis (MS) using a new index.
  
  
  METHODS
  We studied 88 patients with MS. Maximum separation of mitral leaflet tips in diastole in parasternal long-axis and apical 4-chamber views was measured. These two parameters were averaged to yield the mitral leaflet separation index. The index was compared with mitral valve area by planimetry and pressure half-time.
  
  
  RESULTS
  The mitral leaflet separation index was measurable in 76 (86.4%) patients. There was excellent correlation with mitral valve area by planimetry (r = 0.91, P < .001) and pressure half-time (r = 0.86, P < .001) across a wide range of mitral valve areas. Good correlation was found even in atrial fibrillation (r = 0.86 and r = 0.79, respectively). The index could discriminate between hemodynamically significant and insignificant MS (P < .001). An index of 0.81 cm or less predicted severe MS with 92.3% sensitivity and 100% specificity whereas a value of 1.11 cm or more identified mild MS with 85.7% sensitivity and 100% specificity.
  
  
  CONCLUSIONS
  The mitral leaflet separation index is an independent and reliable measure of MS severity that is easy to measure.
authors.affiliation: Heart Institute, National University Hospital, Singapore. seowsc@nuh.com.sg
authors.forename: Swee-Chong
authors.initials: SC
authors.lastname: Seow
authors.forename: Lay-Pheng
authors.initials: LP
authors.lastname: Koh
authors.forename: Tiong-Cheng
authors.initials: TC
authors.lastname: Yeo
mesh_terms: D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D008946:Mitral Valve Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology