Diagnosis and evaluation of mitral valve disease using transseptal Doppler ultrasound catheterization

[A history of the clinical research in cardiology]

On January 21 1968, nearly an half-century ago, a small Parisian group of cardiologists presented a directional Doppler prototype making possible the detection of forward and backward flows in the arteries. This princeps report, rapidly followed by the Directional Doppler recording of intracardiac flows, has upset the traditional approach to cardiovascular pathophysiology and launched a new examination method that will spread upon the whole word. Single CNRS researcher among this group of clinical cardiologists, Dr Colette Veyrat recalls this early period….

Cardiovascular applications of the Doppler technique: A long way from birth to scientific acceptance

Analysis of the early developments of cardiac Doppler illustrates a gap, frequently encountered in science, between initial concepts and final acceptance. Acceptance may only emerge as a result of multidisciplinary collaboration and fruitful dialogue between physicians, physiologists, physicists, and engineers. By 1980, after a good deal of trial and error and a long period of incremental improvement, the majority of the theoretic and scientific issues had been defined. The explosive development of Doppler techniques can now intervene to sweep aside the medical community's scepticism.

Quantitative assessment of valvular regurgitations using the pulsed Doppler technique. Approach to the regurgitant lesion

It is now possible with pulsed Doppler to grade the severity of aortic, mitral and tricuspid regurgitations on a quantitative basis. "Indices" were devised, using the measurement of the spatial extent of abnormal Doppler signals. For aortic regurgitation: (1) at the aortic valvular orifice area, by measurement of the regurgitant aortic valvular area and calculation of the valvular regurgitant "index". (2) In the left ventricle outflow tract, by calculation of an "index" combining information from two echographic (short and long axis) planes. For mitral regurgitation: by calculation of the total regurgitant "index" combining information from examination of the annulus in short axis, and of the left atrium in long axis view. For tricuspid regurgitation: at the tricuspid annulus, by averaging the depth of the reversal wave on two samples recorded using various echographic approaches. A group of patients with aortic (42), mitral (55) and tricuspid (57) regurgitation proven by invasive procedures, was investigated with this procedure using a 3 MHz two dimensional pulsed Doppler echo device. Correlative coefficients between the Doppler grading and that provided by independently performed invasive procedures on a three point scale, ranged between 0.66 and 0.88, with significant differentiation of mean values of indices (P less than 0.01 to P less than 0.001) for each grade of severity. Success in the Doppler grading of severity of the regurgitations requires (1) a sampling as close as possible to the lesion, and optimally at ther very site of the lesion, (2) the largest explorable area at the site of the lesion, (3) the relevancy of the selected Doppler parameter in order to take into account, as much as possible, the three dimensional configuration of the regurgitant jet. Moreover, this mapping procedure provides a pathophysiological insight of the regurgitant lesion for left-sided regurgitations.

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).

Non-invasive pulsed Doppler study of mitral stenosis and mitral regurgitation: preliminary study

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Non-invasive observations on initial low frequency vibrations of the first heart sound--correlation with the 'presystolic' murmur in mitral stenosis

The initial low frequency component of the first heart sound, 'M', has been studied in normal subjects, and in patients with vario-s prosthetic mitral valves and with mitral stenosis, using simultaneous low frequency phonocardiography, echocardiography, and apex cardiography. The techniques showed 'M' to have a constant morphology in preisovolumic systole. In mitral stenosis, 'M' and the preisovolumic 'presystolic' murmur appear to be the same phonocardiographic phenomenon. While 'M' was present in sinus rhythm, augmentation of this normal vibration occurred particularly during the short cycles of atrial fibrillation. Leaflet coaption and movement of the ventricular wall as detected echocardiographically do not appear to play a role in its pathogenesis but the sound could emanate from the ventricular wall as it tautens and decreases its compliance at the onset of systole.

Relation between phasic mitral flow and the echocardiogram of the mitral valve in man

Ten patients without valvular disease were studied by ventriculography, and the rate and pattern of phasic blood flow into the left ventricle were determined by ventricular volume determinations at intervals of 33 ms during a single diastolic filling period. The derived left ventricular inflow patterns were then compared with the echocardiographic mitral EF slope obtained no more than 25 minutes before left ventriculography. The steepness of the EF slope was found to be inversely correlated with the time required to reach peak inflow velocity (r = 0.80, P less than 0.01) and directly correlated with the peak left ventricular inflow velocity divided by the time required to reach peak velocity (r = 0.72, P less than 0.05). No correlation was found between mean flow velocity into the left ventricle and the EF slope (r = 0.40, P = NS). A significant inverse correlation was found between the EF slope and the fraction of the diastolic filling period elapsed when 50 per cent of the filling volume had entered the left ventricle (r = 0.85, P less than 0.01). These findings suggest that the time required to reach left ventricular peak inflow velocity is one of the determinants of the mitral EF slope.

Non-invasive recording of mitral valve flow velocity patterns using pulsed Doppler echocardiography. Application to diagnosis and evaluation of mitral valve disease

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