Biomedical subjects

D Kalmanson

Publications and source records attributed to D Kalmanson.

At least 55 records · Page 3Linked to original sources

PubMed1976

[Recording by transcutaneous route of the normal and pathological curves of mitral blood velocity by pulsed emission and modulated reception Doppler technic associated with echocardiography. Preliminary report].

A new method, derived from the Pulsed Doppler Technique is proposed for recording transcutaneously the Mitral Valve flow velocity curves in normal subjects and diseased states. The recorded curves are described and found similar to those obtained experimentally in animals or clinically using CW doppler cardiac catheterization. Characteristic anomalies are found for each type of lesion (stenosis and/or regurgitation) and correlated with the degree of its severity. The authors conclude that this technique may provide a new non-invasive method for diagnosing and assessing Mitral Valve disease.

Adolescent↗

PubMed1976

Opening snap and isovolumic relaxation period in relation to mitral valve flow in patients with mitral stenosis. Significance of A2--OS interval.

In 15 patients with pure or predominant mitral stenosis and in a control group of 11 patients without mitral stenosis the blood flow velocity through the mitral valve orifice was recorded by means of a directional Doppler ultrasound velocity catheter introduced transeptally and positioned in the orifice of the mitral valve. A simultaneous surface phonocardiogram was obtained. The timing of the mitral opening snap in relation to the blood velocity record of the flow through the valve supported the hypothesis that the opening snap is due to a sudden tensing of the valve leaflets by the chordae tendineae. Determination of the exact time of mitral valve opening, made possible by the blood velocity record, led to the division of the classical A2-0S interval (aortic valve closure to opening snap) into two components representing respectively the diastolic isovolumic relaxation period and the time of excursion of the mitral valve cusps. The durations of the isovolumic relaxation period were compared with those in the control patients and were found to correlate with the severity of the mitral stenosis, whereas those of the excursion time of the mitral cusps were influenced by the presence or absence of mitral valve calcification.

Adult↗

PubMed1975

Cardiovascular investigations and fuzzy sets theory.

Examining the circumstances that often lead modern, mechanistic cardiovascular research into areas devoid of practical significance, we suggest that our approaches, instead of our technology, are inadequate. A method for processing information, built on the concept of "fuzzy sets," is described as a potential way out of this dilemma. This system deserves application to clinical problems, perhaps together with more classic quantitative methods, because of its practical consequences and the conceptual revitalization it may bring.

Aortic Valve Insufficiency↗

PubMed1975

Normal pattern and physiological significance of mitral valve flow velocity recorded using transseptal directional Doppler ultrasound catheterization.

In 10 cardiac patients in whom an organic lesion of the mitral valve was exluded by standard investigation procedures during which a diagnostic transseptal catheterization for pressure measurements in the left heart was performed, the authors placed a directional Doppler ultrasonic catheter tip velocimeter at the site of the mitral ring and recorded the mitral flow velocity traces. The pattern of these normal curves is presented and a physiological interpretation proposed. The relation between the mitral flow velocity and low volume curves is discussed in the light of present experimental data on mitral valve flow velocity profiles and variations in size of the mitral orifice. The authors concluded that the flow velocity curves obtained by the Doppler technique constitute a valid physiological reference system for the study of the mitral valve flow velocity tracings that can be recorded in the various forms of mitral valve disease.

Adult↗

PubMed1975

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

In 33 patients with confirmed mitral valve disease, the mitral valve flow velocity traces were recorded by means of a directional Doppler ultrasonic velocimeter using the transseptal route, and correlated with the clinical and haemodynamic data. In all cases, characteristic anomalies of the mitral flow velocity patterns were noted and could be related to the type of lesion, stenosis, regurgitation, or a combination of these. Furthermore, specific patterns of the flow velocity traces were shown to correlate satisfactorily with the degree of severity of the disease. The authors propose a pathophysiological interpretation of the anomalies of the velocity patterns, based on turbulence for stenosis and backward flow wave for regurgitation. They conclude that the transseptal directional Doppler catheterization provides a new reliable method for establishing the diagnosis and grading the severity of mitral valve disease using pattern recognition, and, moreover, offers a new approach to the understanding of mitral haemodynamic disturbances on a beat-to-beat basis.

Adult↗

PubMed1974