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D Kalmanson

Publications and source records attributed to D Kalmanson.

87 records · Page 5Linked to original sources
PubMedDate not supplied

Applications of pulsed Doppler flow mapping to left sided cardiac valvular lesions.

The flow mapping procedure has been developed in parallel to the standard pulsed Doppler procedure. It has a different purpose--picking up flow signals at the site of lesions rather than calibrating velocities--and has its own methodology, developed within the last six years. On the basis of invasive correlations performed in 267 cases of valvular heart disease, we review the three-fold purpose of the flow mapping technique: diagnosing lesions, relying on the presence of flow anomalies; assessing their severity, relying on the spatial spreading of these flow signals; and identifying the site of the lesion, which is a specific advantage, relying on the anatomical location of these flow signals and/or on the direction of the jets. For example, using this technique, it is now possible to easily differentiate a cusp tear from a leak of a bioprosthesis, to measure the size of the leaks, and to reconstruct the image of aortic or mitral stenotic areas. These optimal results are only obtained using an appropriate methodology which mainly includes a) the selection of adequate two-dimensional short axis planes in order to explore the diseased valve in its entirety, because of frequent assymetrical orifices, and to pick up the jets at their starting point, b) measurements of the abnormal areas, c) when jets are studied, a three dimensional approach is required in order to cope with the three dimensional nature of the jet and to make available the calculation of three dimensional indices of severity.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗
PubMedDate not supplied

Color and pulsed Doppler studies of atrial flow dynamics in normals and adult patients with uncomplicated atrial septal defects.

Left and right atrial flow dynamics were compared by means of color and pulsed Doppler in order to study whether color Doppler could reliably provide differentiation between normals [15] and patients without atrial shunt at catheterization [12], vs patients with confirmed atrial septal defect [12]. The procedure consisted of sequential analysis of colored images throughout the cardiac cycle using an apical approach. In addition pulsed Doppler indices were calculated from both annular traces, relating diastolic early (E) and late (A) filling waves at each annulus (E/A); E and A waves were also summed (E + A), and the sum was related between both annuli (Tricuspid/Mitral ratio). Sequential analysis had a 100% sensitivity and specificity for the diagnosis of atrial septal defect, showing an asymmetrical pattern with predominant images in the right atrium, from the 2nd half of systole till End-diastole, vs the symmetrical 'Horseshoe' pattern found over both atria for control subjects. It avoided diagnostic errors due to overriding septal images in systole in 44% of controls. There also was a significant increase of the Tricuspid/Mitral ratios, (for duration and velocity time integral of waves) in patients with atrial septal defect. The correlation coefficient between ratios and values of the Pulmonary/Systemic flow ratio invasively calculated for 10 patients was respectively 0.6 and 0.7 (p less than 0.01). Sequential analysis of colored images appears highly reliable for the diagnosis of atrial septal defect; anomalies of ratios, although of moderate value for predicting shunt magnitude, substantiate the inequality of atrial fillings.

Adolescent↗
PubMedDate not supplied

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).

Adolescent↗
PubMedDate not supplied

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.

Adult↗
PubMedDate not supplied

Respective timing of maximal color Doppler jet areas and of peak velocity of jets in left-sided valvular lesions: clinical implications.

Time intervals between the R wave of the electrocardiogram and maximal dimension of jet areas of color Doppler and the R wave of the electrocardiogram and peak velocity of valvular jets of continuous-wave Doppler were compared by use of paired and correlative studies for a group of 55 patients with a total of 71 left-sided lesions. Mean values of both time intervals, mean difference, and its standard error were equal to zero for stenoses. Time intervals of 71% for mitral stenosis and 52% for aortic stenosis did not differ by more than 0.01 second; correlation coefficients were 0.96 for mitral stenosis and 0.85 for aortic stenosis. For regurgitations, differences in mean values and a mean difference with a standard error were found but remained unsignificant. However, the percentage of differences in time intervals below or equal to 0.01 second decreased to 35 for aortic regurgitation and 13 for mitral regurgitation, which showed the widest 95% range of differences. Correlation coefficients were 0.84 for the aortic regurgitation and 0.33 for mitral regurgitation. Thus the close relationship of time intervals suggests that standardized timing of area measurements at peak velocity is feasible for stenoses and remains under consideration for aortic regurgitation. Timing of measurements should remain empiric for mitral regurgitation.

Adolescent↗