Biomedical subjects

G Beulcke

Publications and source records attributed to G Beulcke.

At least 19 recordsLinked to original sources

PubMed1994

Three-dimensional optical analysis of chest wall motion.

A method for kinematic analysis of chest wall motion is presented, based on a television-image processor that allows a three-dimensional assessment of volume change of the trunk by automatically computing the coordinates of several passive markers placed on relevant landmarks of the thorax and abdomen. The parallel computation used for the image processing allows for a real time recognition of the passive markers with the necessary accuracy. A geometric model also allows the online computation of the contribution to the chest volume by the different parts. For this purpose, the model presented here is based on 54 tetrahedrons that can be grouped into 9 compartments and 3 sections representing 1) upper thorax (mainly reflecting the action of neck and parasternal muscles and the effect of pleural pressure), 2) lower thorax (mainly reflecting the action of diaphragm and the effect of pleural and abdominal pressure), and 3) abdomen (mainly reflecting the actions of diaphragm and abdominal muscles). By this model, the volume can also be split into three vertical sections pointing out asymmetries between the right and left sides. The method is noninvasive, nonionizing, and leaves the subject maximum freedom of movement during the test, thus being suitable for routine clinical analysis. The monitoring of the subject can be prolonged in time and can be performed in different postures: standing, sitting, and supine. The method was tested on 12 healthy subjects showing its good accuracy, reliability, and reproducibility.

Abdomen↗

PubMed1994

[Pulmonary involvement in scleroderma assessed with high-resolution computerized tomography and functional tests].

This study was aimed at investigating and analyzing lung involvement in scleroderma patients with different imaging methods, toward a rational diagnostic approach. Twenty-four patients with systemic sclerosis were examined with pulmonary function tests (PFT), spirometry and diffusing capacity for carbon monoxide (DLCO), chest radiography and high-resolution Computed Tomography (HRCT). Abnormal findings were present in 42% of cases on X-ray films and in 71% of cases on HRCT images. PFT was abnormal in the spirometries of 42% of cases and in DLCO tests in 50% of cases. The most common findings at HRCT were the small reticular and the ground-glass patterns. HRCT emerged as the most effective method to evaluate lung involvement in systemic sclerosis. In our series, HRCT allowed possibly curable lung lesions to be differentiated from incurable ones. However, HRCT is suggested in the patients with impaired pulmonary function to allow treatment choice; on the contrary, in the patients with no functional impairment, HRCT adds little information to clinical findings, showing only limited focal lesions.

Adult↗

PubMed1982

[Cardiologic aspects of Friedreich type heredoataxia].

The authors performed ambulatory electro-vectorcardiography polycardiography and echocardiography in 18 patients with typical Friedreich's disease, and 6 patients with atypical forms of hereditary spino-cerebellar ataxia classified on e basis of the degree of neurological involvement, without clinical signs of cardiocirculatory failure. The ECG and VCG recording commonly showed appearances suggestive of myocardial "necrosis" and were of little value in the differential diagnosis between typical and atypical forms of Friedreich's ataxia. This limitation also applied to the kinetocardiogramme which was sometimes pathological confirming the echocardiographic diagnosis of symmetric LV hypertrophy and of septal hypokinesia despite normal ECG and VCG. The systolic time intervals and echocardiographic parameters of the interventricular septum were more helpful in the differential diagnosis. Hypertrophic cardiomyopathy, usually symmetric, was observed in about 70 p. 100 of typical and only rarely in atypical forms of Friedreich's disease. The symmetric or asymmetric hypertrophy was associated with reduced left ventricular performance in less than 20 p. 100 of typical Friedreich's disease, systolic anterior motion of the mitral valve and other signs of dynamic left ventricular outflow tract obstruction were not observed in any of these patients. The correlations between the degree of neurological disability and the cardiac abnormalities, were, in general, disappointing compared with other reported series. The cardiac investigation of patients with Friedreich's disease remains valuable from the point of view of recent pathological hypotheses of a metabolic abnormality with eventual therapeutic implications.

Adolescent↗

PubMed1979

[The evolution of cardiac impairment in Duchenne's muscular dystrophy. Electrovector-cardiographic, polycardiographic and echocardiographic aspects (author's transl)].

The Authors have submitted to an electrocardiographic, vectorcardiographic, mechanocardiographic and echocardiographic investigation 4 cases with Duchenne's disease, which had already been studied by the Authors several years before. The longitudinal study has demonstrated, above all, the striking capacity of the electrocardiographic aspects of the disease to evolve from a normal to a "pseudo-necrotic" pattern. Such evolution, among other things, provides an important argument against the interpretation that attributes the electrocardiographic and vectorcardiographic changes in the initial stages of the disease to a persistence of a QRS loop of infantile type on a genetic basis. But for rare exceptions, the systolic time intervals and kinetocardiogram, which showed early indicative changes on the first examination, have successively shown easily predictable behavior considering the poor cardiovascular conditions of the patients on the second examination. The echocardiogram has proved useful in demonstrating the morphological and functional changes of the ventricular walls and of the interventricular septum, besides the eventual associated mitral valve prolapse. The echocardiographic evaluation of the left ventricular performance in quantitative terms, however, seems somewhat unreliable owing to the difficulty of obtaining technically good images, due to the thoracic deformity. The dystrophic changes recently observed in the myocardium even at ultrastructural level can probably explain not only the electrocardiographic and vectorcardiographic abnormalities but also the kinetocardiographic and echocardiographic changes. Among the above mentioned theoretical and practical considerations the possibility should be underlined that some cases of cardiomyopathy labelled as "primary" are in fact unrecognized dystrophic cardiomyopathies.

Adolescent↗

PubMed1979

On some cardiological aspects of Steinert's disease (myotonic dystrophy).

The authors investigated 10 ambulant patients with myotonic dystrophy, under 40 years of age (mean 22.3 years) and free of subjective heart complaints. Not only Ecg alterations but also kinetocardiographic changes and anomalies of the systolic intervals were rarer and milder than those found in patients with other neuromyopathies, namely Friedreich's disease and Duchenne's disease. This observation suggests that, at least in older patients, not all the cardiac alterations usually attributed to myotonic dystrophy are really imputable to the disease. On the other hand, the observed echocardiographic alterations (reduction of per cent systolic-diastolic variation of internal diameter of the left ventricle and/or the ejection fraction) apparently indicate an early tendency to modification of left ventricular function in patients with myotonic dystrophy. Since other authors have found cardiac anomalies in this disease before the onset of any neurological manifestations, the possibility emerges that some cases of myocardial disease interpreted as "primitive" might in reality be secondary to undetected myopathy.

Adolescent↗

PubMed1976

[The heart in myasthenia gravis. Electrocardiographic, cardiodynamic and kinetocardiographic aspects in 18 cases].

Eighteen patients with myasthenia gravis, second-stage (A or B) according to Ossermann and Genkins, and of young age, were examined as outpatients from the cardiological point of view. Clinical and radiological examination of the heart and large vessels revealed no pathological features. Electrocardiographic abnormalities (including one case of ventricular preexcitation syndrome and one of subepicardial ischemia) were detected in three patients (16,6%). Among the various left ventricular systolic time intervals, only the deformation time was somewhat off normal limits in some cases, but the difference was not statistically significant. In over one-third of the cases, conversely, the kinetocardiogram revealed paradoxical systolic outward movements, indicative of myocardial dyskinesis or dissinergy. The essential normality of systolic time intervals in the presence of manifest abnormalities of the kinetocardiographic curve may be explained by the smallness of hypokinetic or dyskinetic areas, whereby the ejection fraction was not reduced. In general, the ECG and kinetocardiographic tracings showed no tendency to change under the effect of orally administered pyridostigmine.

Adolescent↗

PubMed1976

Correlations between lung-transfer factor, ventilation, and cardiac output during exercise.

In nine healthy and young subject of either sex, undergoing three or four rounds of muscular exercise of increasing severity on a bicycle ergometer, the authors investigated the behavior of the lung transfer factor (Dlco), pulmonary ventilation (V), alveolar ventilation (Va), and cardiac output (Q). In all instances they found a positive linear correlation between DLCO and oxygen consumption (VO2), at least up to 70% of maximum oxygen consumption (Vo2max) (r=0.935;p less than 0.001). Dlco was found to increase linearly as a function of increasing V (R=0.898;P LESS THAN 0.001) AND EVEN MORE SO OF INCREASING Va (r=0.919; p less than 0.001). Also the relationship between Dlco and Q appeared linear in all subjects (r=0.926; p less than 0.001). On the other hand, individual Dlco values showed considerable scatter at equal Vo2, V, Va, and Q values. Among the factors responsible for the increase of Dlco during muscular exercise, in addition to increased ventilation and cardiac output, the authors suggest the possible role of the greater desaturation of mixed venous blood and variations of hemoglobin affinity for CO.

Adolescent↗

PubMed1975

[The ventilation-perfusion ratio, with special reference to muscular exercise].

The values of VA/Q obtained at rest in 12 normal subjects undergoing cardiac catheterization in a supine position were between 0.63 and 1.695, with a mean of 1.142 +/- 0.295. The VA/Q values obtained in another 10 healthy subjects tested in a sitting position with a rebreathing method for calculating Q. were somewhat less scattered (between 0.77 and 1.50), and also lower (mean 0.975 +/- 0.210). A highly significant correlation was demonstrated during muscular exercise on the bicycle ergometer (sitting position), both between oxygen consumption and alveolar ventilation and between oxygen consumption and cardiac output. However, since at various submaximal work loads cardiac output increased much less than alveolar ventilation, the overall VA/Q ratio showed a progressive increment with increasing oxygen consumption.

Adolescent↗

PubMed1973