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J M Mossard

Publications and source records attributed to J M Mossard.

At least 55 records · Page 3Linked to original sources
PubMed1986

[Spatial ventricular gradient studied by computerized vectorcardiography. Normal and pathological values. Interpretation and clinical evaluation].

The ventricular gradient is a reflection of uneven ventricular repolarisation. Until recently is was only appreciated in the frontal plane of the classical electrocardiogramme and expressed as the sum of the vectors representing the surfaces under the QRS complex and T wave. We used computerised vectorcardiography to obtain a more exact evaluation of the size and spatial orientation of the vector gradient. The spatial vector gradient was calculated in a control group and in a number of pathological conditions. The reference values were established in 70 normal subjects with a mean age of 36 +/- 21 years: 0.092 +/- 0.016 m V.s for amplitude: 38.4 degrees +/- 6.1 for thesite and 21.6 degrees +/- 8.7 for the azimuth. The size and spatial orientation of the ventricular gradient can be used to define normal limits and to distinguish subgroups by using the values of the site and azimuth. The spatial ventricular gradient is a new approach to defining the limits of normality in poorly understood abnormalities of ventricular repolarisation. It may also be useful in the comprehension of certain forms of cardiac arrhythmia related to desynchronisation of ventricular repolarisation.

Adolescent↗
PubMed1986

[Nuclear magnetic resonance in the diagnosis of aortic diseases].

The diagnostic value of nuclear magnetic resonance imaging was assessed in a number of aortic pathologies: aneurysms of the thoracic and abdominal aorta, sinus of Valsalva aneurysms and dissection of the aorta. The imager was equipped with a resistor magnet providing a field of 0.15 Tesla. An electrocardiographic gating system was perfected. The images obtained were very satisfactory as they provided three dimensional morphological information and a qualitative assessment of blood flow. Further studies are now required with comparison with other invasive and non-invasive diagnostic methods to determine the clinical role of NMR imaging and to evaluate the diagnostic sensitivity and specificity of this new technique.

Aortic Dissection↗
PubMed1986

[Nuclear magnetic resonance. Our preliminary experience on the normal heart and in various cardiopathies].

Nuclear magnetic resonance imaging (NMRI) is applied in our department to the study of the normal heart and in aortic, pericardial and myocardial pathologies: aortic aneurysms, hypertrophic cardiomyopathies, myocardial infarction, pericarditis and congenital cardiopathies. The apparatus used consists of a resistive magnet which provides a field of 0.15 Tesla. Synchronisation with the electrocardiogram leads to improvement of the cardiac signals. The documents obtained are promising to the extent that information concerning cardiac structure is provided in three planes (frontal, sagittal and horizontal) and is complementary to that provided by echocardiography, isotopic techniques and contrast angiography. The future potential of the method is considerable, particularly in the area of tissue characterisation.

Aorta↗
PubMed1986

[Carotid sinus syndrome of mixed cardioinhibitory and vasodepressive form. Value of sequential atrioventricular stimulation].

The authors report an observation of cardioinhibitory and vasodepressive carotid sinus syndrome. The vasodepressive response was analyzed by electrophysiological exploration with determination of changes in arterial pressure. This pressure is increased automatically by the "pacemaker effect of a ventricular corrective response. The pressure drop can be limited by sequential stimulation. A review is given of the results and methods of cardiac stimulation in sinocarotid hypersensitivity.

Aged↗
PubMed1984

[The spatial vectorcardiogram loop. Estimation of its planarity by the calculation of a distortion coefficient. Trial of clinical evaluation].

Automatic techniques for interpreting the electrical activity of the heart are based more and more on vectorcardiographic parameters, especially information provided by the spatial vectorcardiographic loop. This data has been shown to be a useful complement to classical electrocardiography. The aim of this study was to define a method of calculation of the planes of the vectorcardiographic loops of depolarisation and repolarisation, and to calculate a coefficient of left-sidedness obtained by the sum of squares of the distances between the points on the loop in the plane. This value is then normalised with respect to the size of the loop. Normal values of this coefficient were first defined in a healthy reference population of 70 subjects: the values are expressed in (MV/10)2 or in mm2, and are 0,28 +/- 0,05 for the QRS and 0,0026 +/- 0,0008 for the ST-T. The coefficient was then calculated in different pathological groups, the diagnosis of which had been formally confirmed: ventricular hypertrophy, valvular heart disease, conduction defects, coronary artery disease. The highest values (four times normal) were obtained in right ventricular hypertrophy, right bundle branch block and infarction associated with conduction defects. The discriminative value of the coefficient of left-sidedness is discussed with the aim of distinguishing the normal from the pathological.

Adult↗
PubMed1981

Evaluation of myocardial perfusion and left ventricular function by 201T1 scintigraphy after dipyridamole.

201T1 myocardial imaging was performed at rest and after dipyridamole (0.44 mg/kg) on 50 patients with known or suspected ischemic heart disease. The dipyridamole had no effect in 14 patients (group Dip.0). In 17 patients (group Dip +/-) it significantly modified the contrast of the rest image (by increasing or decreasing a rest perfusion defect). In 19 patients (group Dip - Steal) the drug induced a paradoxical response interpreted as a coronary steal effect (an active region at rest becomes hypoactive after dipyridamole while an underperfused region at rest improves). All patients underwent coronary arteriography and left monoplane ventriculography; results were interpreted in relation to these angiographic data. The mean percentage of stenoses (per patient) was about the same in the three groups but it was found that, despite these stenoses, the patients of the group Dip - Steal had a good left ventricular function (EF = 0.62 +/- 0.12). On the other hand, the ejection fraction was very poor in the two other groups (0.50 +/- 0.17 and 0.48 +/- 0.17). Moreover it was found that: (1) the frequency of high grade or even complete obstruction was notably less in group Dip - Steal (P less than 0.05); (2) the frequency of angiographically visible collaterals was higher in group Dip - Steal (P less than 0.05); (3) the left anterior descending artery was less diseased than the right coronary artery in group Dip - Steal (P less than 0.05). These results have a real prognostic value for the assessment of the preserved cardiac performance in Dip - Steal patients despite severe stenoses, and are discussed in terms of compensatory collateral circulation and preservation of the coronary-flow reserve in the myocardium distal to a critical stenosis.

Coronary Circulation↗
PubMed1977

[Concealed permanent ventricular reentry and paroxysmal ventricular tachycardia by circulatory movement].

Endocavitary recording in a patient with attacks of ventricular tachycardia demonstrated a late potential which activated the bundle of His in a retrograde fashion, and the right bundle branch in a forwards direction. This late potential is evidence of a persistant ventricular microeentry which cannot be seen on the peripheral leads. In certain conditions which have been studied, this localised microreentry leads to ventricular tachycardia by macroreentry using the branches of the bundle of His. Tanks to this unusual case, we were able to study the effects of certain anti-arrhythmic drugs on the micro- and macroreentry circuits. By these means a therapeutic solution has been found for paroxysms of ventricular tachycardia.

Anti-Arrhythmia Agents↗
PubMed1970

[Fabry's disease].

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Angiokeratoma↗