Anatomic and functional evaluation of pure and associated mitral stenoses using the echo-Doppler scanner technique

Twelve normal subjects, 18 control patients and 25 patients with mitral valve lesions (MVL), including 10 pure stenoses (MS), and 15 associated regurgitations (MS + MR) were investigated using a 2-dimensional (2D) pulse echo Doppler procedure, the latter group before open heart surgery. The Doppler signal output consisted of an audio-signal and of a graphic display including an analogue flow velocity trace and a frequency spectrum (Time Interval Histogram). The investigation was two-fold. (1) Diagnosis and assessment of severity of MVL comparing 2D echo and Doppler reliability. The main criteria for diagnosis relied, firstly for the 2D pulsed echo technique on the determination of the planimetric mitral valve area (MVA) for MS and on the finding of an increased annulus diameter for MR, and secondly for the Doppler technique, on the detection of diastolic (MS) and systolic (MR) anomalies of the mitral flow velocity patterns. (2) 2D echo-cardiographic assessment of the mitral apparatus (valves, annulus, subvalvular apparatus), studied on the basis of quantitative and qualitative data. Independently performed correlations with catheterization, angiographic and surgical data showed that a positive diagnosis of MS was obtained in all cases, both with 2D echo and Doppler techniques with a specificity of 92% for the former and 96% for the latter. The assessment of the severity of lesions was satisfactory in 88% of cases for the Doppler, and in 80% of cases for the 2D echo technique with a linear correlative coefficient at 0.83 for the value of MVA measured at catheterization and echocardiography. For MR, a net advantage in diagnosis was found for the Doppler technique (sensitivity of 93%, specificity of 92%) as compared with the 2D echo technique (sensitivity of 33%, specificity of 82%), and also for the assessment of the severity (60% for 2D echo and 85% for Doppler). Furthermore, Doppler assessment of the site of regurgitation and of the direction of the regurgitant jet was in agreement with all the cases also submitted to invasive investigations. Quantitative data obtained by the 2D echo technique for the assessment of the annulus diameter, and of the quality of mitral valve tissue (pliable, fibrous, calcified) or subvalvular apparatus (discrete, moderate, severe alterations), significantly differentiated normals from patients, but no clear-cut separation appeared for patients between close types of alterations. A better assessment was achieved from qualitative data for mitral valve tissue (76% of cases), and subvalvular apparatus (84% of cases).