Résumé : Fifty-five consecutive adult patients with mitral stenosis (MS) were investigated by Doppler echocardiography, to assess the severity of MS. The measurement of mitral valve area (MVA) by cross-sectional echocardiography (CSE) was considered as the reference method, because catheterization data are often inadequate when combined lesions are present. Doppler MVA was calculated from apical mitral flow using the pressure half-time method. Adequate Doppler recordings (52 on 55) were easier to obtain than adequate CSE images. The correlation between both methods was excellent (r = 0.90, SEE: 0.42 cm2) despite systematic underestimation of MVA by Doppler versus CSE. From our data, the following regression equation could be drawn, providing MVA from Doppler measurements: MVA = 250 (pressure half-time)-1 +0.15, where the area is in cm2 and half-time in ms. Both severe and mild MS were identified by Doppler with enough accuracy for clinical use. Reproducibility, inter and intraobserver variability were better for Doppler than for CSE. We conclude that Doppler seems particularly suitable for noninvasive quantification of MS and for patient follow-up.