A new Doppler imaging measurement in aortic stenosis: the contour length of the jet origin flow area. Relationships between both, with usual Doppler data and left ventricular hypertrophy.

Plainmetry of stenotic aortic jet origin flow areas was performed using transthoracic Doppler imaging, with measurement of the contour length of flow areas and calculation of a contour/area (C/A) Doppler ratio on a group of 75 patients with aortic stenosis ranging from 0.27 to 2.44 cm(2). The purpose was to study correlations of these data with the usual Doppler data and with left ventricular hypertrophy. The "r" coefficient between plainmetered flow areas and those calculated by the continuity equation method was 0.89. Mean values (SD) of data were: areas: (plainmetry) 1.00+/-0.59 cm(2), (continuity equation ) 0.91+/-0.42 cm(2), contours: 5.6+/-1.6 cm, C/A: 0.66+/-0.25, maximal and mean pressure gradients: 68+/-34 and 37+/-21 mmHg, left ventricular hypertrophy: 138+/-30 g/m(2) BSA (vs. 100+/-18 in normals). All values except age, gender and BSA, differed significantly (p<0.001) between areas below or over 0.85 cm(2). Other correlations between parameters were significant (p<0.01 to 0.001), but with lower "r" coefficients due to widely scattered individual values. Contours increased much less rapidly than areas did, and were correlated with left ventricular hypertrophy only when coupled in the C/A ratio, with a higher "r" coefficient (0.62) tha areas (0.52). Study of both areas and contours helps to approach the geometry of the orifice. This suggests that the individual geometry of the stenosis mighty weigh on the left ventricular mass growth, as an associated factor for a given decrease in stenotic area.