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D Pellerin

Publications and source records attributed to D Pellerin.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Contribution of doppler imaging of the myocardium to the study of cardiomyopathies].

Colour Doppler imaging (CDI) is a recent method of evaluation of cardiomyopathy based on intra-myocardial abnormalities. CDI provides quantitative assessment of myocardial wall motion both circumferential by studying the movements of the myocardium and longitudinal by studying the movements of the mitral annulus. The harmonious decrease in velocity between the endocardium and epicardium disappears in pathological conditions, showing disorganisation of wall motion within the myocardium. The decrease in the early diastolic transmural velocity gradient in patients with cardiomyopathy indicates diastolic dysfunction independent of the left ventricular systolic function. In addition, CDI is more sensitive than conventional Doppler echocardiography with grey scale because it enables earlier detection of changes induced by low-dose dobutamine, allowing distinction between trained athletes and patients with hypertrophic cardiomyopathy. The velocities of the mitral annulus help to prevent errors of interpretation of mitral blood flow as they are relatively independent on the left ventricular preload.

Cardiomegaly↗
PubMed1997

Preejectional left ventricular wall motion in normal subjects using Doppler tissue imaging and correlation with ejection fraction.

Relations have been demonstrated between the preejection period (PEP) and indexes of left ventricular (LV) systolic function. Doppler tissue M-mode imaging has the capability to measure wall velocities and to display as colored strips within the walls velocity reversals representing changes in direction of wall motion. To document LV preejectional wall motions, this procedure was performed on 16 normal subjects with a twofold purpose: to measure septal and posterior preejectional intramyocardial velocities and durations and to correlate preejectional parameters with LV ejection fraction (LVEF). Parasternal M-mode images of simultaneously recorded walls were digitized. Subendocardial wall velocities were measured every 3.8 ms from the Q wave to the onset of ejection. Total duration measured from Doppler tissue and flow traces was compared in 10 subjects. PEP total duration did not differ between both walls or techniques. Several adjacent velocity reversals with mirror signs in opposite walls were substantiated by 2 to 5 colored strips. Colored strips corresponding to the same sign in each wall had a progressively damped velocity amplitude (septum 19 +/- 8, -21 +/- 10, 15 +/- 7, -8 +/- 5, 4 +/- 2 mm/s; posterior wall -13 +/- 16, 11 +/- 7, -8 +/- 5, 9 +/- 6, -2 mm/s). Peak velocity values of opposite signs significantly differed between both walls (p <0.0001). Absolute values differed only for colored strips 2 and 3 (p <0.009). Strip 2 featured a simultaneous early inward motion of both walls toward the LV cavity with significantly prolonged duration (p <0.0001). The only positive correlation with LVEF was found for peak velocities of strip 2 in the posterior wall (r = 0.71, p <0.006). Thus, the posterior wall and its inward motion velocities have potential for future clinical implications.

Adolescent↗
PubMed1997

Staphylococcal necrotizing fasciitis in the mammary region in childhood: a report of five cases.

OBJECTIVE: Necrotizing fasciitis is a highly lethal soft tissue infection rarely reported in childhood. The initiating site is usually a local trauma or a surgical wound. We observed five cases of necrotizing fasciitis the initiating site for which was the mammary region and discuss their management. STUDY DESIGN: We describe these five patients and review the clinical characteristics of their presentation. RESULTS: Staphylococcal necrotizing fasciitis was observed in the mammary region in all five cases. Four children were newborn infants with a mammitis preceding the onset of necrotizing fasciitis. Surgical débridement was done only after the fourth day from onset of illness. All children were discharged in good condition after 1 month. Two have been followed until puberty, with destruction of the mammary gland in one case and good development in the other one. CONCLUSION: Mammitis may be the initiating event for necrotizing fasciitis in neonates. Necrotizing fasciitis is a life-threatening disease; patients require early intensive care, parenteral antibiotic therapy, and surgical débridement. In a few instances surgery can be carefully delayed until the necrotic area is more delineated if the condition is diagnosed early during disease evolution and appropriate treatment is instituted in intensive care units.

Anti-Bacterial Agents↗
PubMed1997

Right and left isovolumic ventricular relaxation time intervals compared in patients by means of a single-pulsed Doppler method.

Right and left isovolumic ventricular relaxation time intervals measurements were obtained as follows: from the peak R wave on the electrocardiogram to either the mitral or the tricuspid pulsed Doppler flow trace onset minus the R to end-ejection zero flow crossing of the subaortic (left side) or pulmonary (right side) D flow trace time interval. A ratio was calculated as a percent difference duration between both isovolumic ventricular relaxation time intervals. The aim was to compare isovolumic ventricular relaxation time interval values in 42 healthy controls and to study the changes induced by heart diseases in 27 patients with (1) controlled hypertension without left ventricular hypertrophy, (2) hypertrophic cardiomyopathy, and (3) Cor pulmonale. Mean values of isovolumic ventricular relaxation time intervals significantly differed at paired and unpaired studies, with right isovolumic ventricular relaxation time intervals shorter than those of the left side in all groups (p < 0.001) except for patients with Cor pulmonale. Isovolumic ventricular relaxation time intervals did not correlate with heart rate and moderately correlated with left ventricular mass and age. No significant difference was found between healthy controls and patients with controlled hypertension. Significant changes were found in patients with hypertrophic cardiomyopathy and Cor pulmonale versus healthy controls for both isovolumic ventricular relaxation time intervals. However, significant changes in the ratio were only found in patients with Cor pulmonale (p < 0.005) because of abnormal similar values for both isovolumic ventricular relaxation time intervals. This Doppler method enabled, for the first time, serial comparison of isovolumic ventricular relaxation time intervals with a homologous method. Both isovolumic ventricular relaxation time intervals significantly lengthened with age and with left ventricular indexed mass, but their ratio remained insignificantly changed except for patients with Cor pulmonale. The concomitant right and left isovolumic ventricular relaxation time intervals lengthening in patients with hypertrophic cardiomyopathy and Cor pulmonale suggests interdependence of both ventricles through the septum. This makes recommendable systematic comparison of both sides. The calculation of a ratio, free from the effect of factors intervening on isovolumic ventricular relaxation time intervals, may, in addition, be of diagnostic help.

Adolescent↗
PubMed1997

Adaptation of the rectal wall to distension in children with constipation.

OBJECTIVE: To determine whether there is significant change in the tension-length relationship of the digestive smooth-muscle mechanical function in constipation in children and to examine a new method of analysis of the mechanical properties of the rectal wall. DESIGN: Case-control study. PARTICIPANTS: Thirty children with constipation and 30 control children who did not have constipation. INTERVENTION: Rapid distension of the rectal wall by inflation of a rectal balloon with air. MAIN OUTCOME MEASURES: The in vivo rectal pressure-volume P[t,V] curve was determined according to the quasilinear viscoelasticity law. The recorded pressure was defined as the product of 2 functions: the elastic response P0[V] and the reduced relaxation function G[t], a normalized function of time such that P[t,V] = P0[V] x G[t]. Analysis of variance with repeated measures and modelling (linear for P0[V] and exponential plus constant term for G[t] were used for data analysis. RESULTS: The quasilinear viscoelastic law can be applied to the in vivo determination of the mechanical properties of the rectal wall in controls and in children with constipation. The elastic response was similar in the 2 groups. The reduced relaxation function was significantly different between the 2 groups, with the absence of an asymptotic value in the group with constipation (p < 0.01). CONCLUSION: Distension of the rectal wall with the use of an air-inflated balloon, with this type of interpretation according to the viscoelastic law, is useful in the analysis of chronic constipation.

Adaptation, Physiological↗
PubMed1997

[Myocardial Doppler tissue imaging: past, present and future].

The first Doppler spectral and pulsed tissue recordings in 1992 have given way to a new generation of machines which enable cardiologists to study mechanical events of the myocardium during the cardiac cycle by Doppler tissue imaging. This technique provides valuable information about regional function with quantitative analysis of the velocities within the myocardial wall as opposed to the global qualitative or semi-quantitative character of usual echocardiographic data. The velocity mode is the most commonly used in its three different presentations: two-dimensional, M mode and, more traditionally, pulsed spectral modes. Two-dimensional imaging gives a global view of the different myocardial segments and allows a rapid approximation of the differences of velocities between these segments and of myocardial wall thickness; however, it lacks the temporal resolution of pulsed Doppler and M mode. In addition, M mode with automatic programmes of velocity analysis has the advantage of providing a continuous spatio-temporal recording of the velocities within the myocardial wall, layer by layer. There is a physiological gradient of velocities highest at the endocardium and lowest at the epicardium. Despite the present limitations related to the Doppler principle itself, the technology, and the complexity of myocardial architecture, Doppler tissue imaging is a useful complement to information already available concerning pressures, flow and cardiac structures. The future is promising and should exceed this simple complementarity to existing ultrasound methods. Progress in the fields of ultrasound physics, technology, computerisation for acquisition of two- and three-dimensional imaging should provide a new physiopathological approach to the understanding of wall motion changes during cardiac disease.

Animals↗
PubMed1996

Colour doppler valvar and subvalvar flow diameter imaging versus echo score in mitral stenosis: comparison with type of surgery.

OBJECTIVE: To compare the value of echo score with that of Doppler subvalvar flow broadening in deciding the type of mitral stenosis surgery. PATIENTS: 30 patients, mean age 47 years, with severe stenosis undergoing surgery were divided into two groups according to type of surgery: open heart commissurotomy (group 1, n = 12), or prosthesis (group 2, n = 18). A control group of 10 patients with prosthesis served as reference, representing mild stenosis without subvalvar connection. METHODS: For echo, the score proposed by Wilkins for cross sectional imaging was used. For Doppler, the flow diameters were measured in cm by an independent examiner from the long axis view in early diastole at two levels: (1) at the level of the stenosis (origin flow diameter), and (2) 1.5 cm downstream from the stenosis in the left ventricle (subvalvar flow diameter) with calculation of a Doppler ratio relating these two measurements, expressed as a percentage of broadening. Diagnostic value was compared for both procedures. RESULTS: There was no significant difference in age, mitral valve areas, or haemodynamics for the two groups. Mean values (SD) were: echo score: group 1, 9.83 (1.26) v group 2, 10.8 (8.1), NS; Doppler ratio %: group 1, 44 (24) v group 2, 12 (21) (P < 0.001); control group: 69 (15). The per cent diagnostic value for an open heart commissurotomy of respective cut off points was: Doppler ratio > 25% (range 71% to 87%); echo score < 10 (range 50% to 75%). CONCLUSIONS: The new Doppler ratio diagnostic value agreed better with surgical management, repair or prosthesis, in this study. Thus, it appears to better reflect the subvalvar involvement and changes in kinetics than the echo score alone. This easy Doppler method might become a routine examination for follow up of patients with open heart commissurotomy, to avoid performing repeated transoesophageal echocardiography.

Adolescent↗
PubMed1996

[Drug therapy of heart failure. What choice in 1996?].

The mortality of heart failure remains high despite recent therapeutic progress. The objectives of treatment are to relieve symptoms, but also to improve survival. The secondary objectives are extension of the duration of effort, improvement of the ejection fraction, reduction of arrhythmias and neuroendocrine disturbances, although these criteria are not strictly related to the primary objectives. Diuretics should be used from the first symptoms, but their effect on survival has not been evaluated. Digitalis alkaloids, with no effect on survival, also improve functional signs, even in patients in sinus rhythm. All other positive inotropic agents increase mortality. Nitrates improve symptoms and, when associated with hydralazine, prolong survival. Amiodarone should be reserved to patients with dangerous arrhythmias. Angiotensin converting enzyme inhibitors have the best demonstrated effect on survival and must be used as first-line treatment. Their preventive effect on mortality is limited, except in post-infarction ventricular dysfunction. Beta-blockers, which appear very promising for the improvement of survival, functional signs and ejection fraction, are currently under evaluation. Their mechanisms of action and the choice of the most active drugs have yet to be determined.

Adrenergic beta-Antagonists↗
PubMed1995

[Dynamics of ventricular repolarisation].

The clinical value of assessing the QT interval is obvious as it is a marker of ventricular depolarisation and repolarisation and it allows identification of clinical situations carrying a high risk of ventricular fibrillation and sudden death. Until the last few years, analysis of ventricular repolarisation was based on analysis of conventional surface electrocardiography. Technical difficulties explain the limits of our knowledge of the dynamics of ventricular repolarisation. This situation is beginning to change rapidly by computerised analysis of Holter monitoring, opening up a particularly complex and important field of research. The duration of the QT interval depends on different factors, especially changes in electrolyte balance, effects of certain drugs, and changes in heart rate and autonomic nervous system tone. The difficulty resides in selecting the pertinent data in order to study separately the effects of heart rate and those of the autonomic nervous system. The initial results show that this analysis provides important information for diagnosis and probably prognosis, on the status of the myocardium and the action of the autonomous nervous system. They require confirmation and validation on larger series of patients with different pathological conditions.

Action Potentials↗
PubMed1994

Biofeedback re-education of faecal continence in children.

The purpose of this prospective study was to see if pretreatment anorectal motility can predict successful correction of faecal incontinence with biofeedback. Forty-seven consecutive children, aged 5 to 18 years, were treated. They had been treated for idiopathic constipation with faecal impaction, but had remained incontinent (n = 15), had been operated for congenital anorectal malformations of high (n = 19) or low (n = 2) type, or had a number of organic congenital pelvic abnormalities (n = 11). This consecutive series represents our entire experience with biofeedback for faecal incontinence, in the period from January 1 1983 to December 31 1989. In each patient, at the first session, anorectal manometry was performed. Resting pressures in the rectum, upper anal canal and lower anal canal were measured. The threshold of rectal sensation during distension, the maximal pressure during voluntary sphincteric contraction and the time to half decrease of sphincteric pressure because of muscular fatigue were also noted. The patient was then asked to make a voluntary sphincteric contraction, while the rectum was being distended with the volume at threshold for rectal sensation. In subsequent sessions, the rectum was also distended but without warning the patient, who was congratulated when he or she contracted the sphincter immediately after onset of rectal distension. Full continence was the criterion used to classify re-education as a success. Improvement or no change in continence was considered as failure of the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

LAIT-XPERT VACHES: an expert system for dairy herd management.

An expert system called LAIT-XPERT VACHES, developed to evaluate technical management of dairy enterprises, was tested using case data. The expertise of the system was provided from information obtained from interviews of three dairy management or nutrition experts. LAIT-XPERT VACHES contains over 950 rules and runs on IBM-compatible personal computers. It calculates objectives in milk production, fat and protein production, feeding cost, reproduction, and other areas. In addition, it detects problems and high performance according to these objectives; researches the causes of problems in herd management, feeding, genetics, health, housing, and other areas; and lists conclusions by sector. Using a monthly report of 10 farms registered in the DHI program of Quebec, LAIT-XPERT VACHES issued 92.3% of the conclusions also issued by experts. However, the experts revealed only 53.3% of conclusions reached by the expert system. With Agri-Lait reports of three farms, all conclusions of LAIT-XPERT VACHES were validated by the experts. These results demonstrated that use of an expert system makes it possible to obtain analyses of dairy performance data equivalent to those of human experts.

Animal Feed↗
PubMed1994

Variation of rheological properties of the human rectal wall with distending volume.

Pressure-relaxation curves of in vivo human rectal wall were studied in 30 normal children for 5 volumes of distension, 10-50 ml, to define the conditions of application of the quasi-linear viscoelastic law. Three normalization methods were compared: the use of the maximum pressure of the curve, the use of the first measured point after the rectal distension, and the use of the passive state defined as the inferior envelope of the experimental curve. Analysis of variance with repeated measures was used for data analysis. It was shown that: i) the first relaxation curve, corresponding to a 10-ml distension volume, was significantly different from the other curves (p < 0.0001); ii) the quasi-linear viscoelastic law could be applied to the in vivo determination of the mechanical properties of the rectal wall, when considering the mean level of the measured points; and iii) the shapes of the experimental curves at different level of distension were significantly different (p < 0.0001). We conclude that the hypothesis of quasi-linearity is appropriate, in a first approximation, as a model of rheological properties of the rectal wall.

Adolescent↗
PubMed1993

Evaluation of drug-induced QT interval modifications in dynamic electrocardiography: the case of bepridil.

Drug-induced modifications of QT interval are usually assessed through formulae defining the corrected QT interval "QTc". They are all based on the assumption that the correction is adequate, and that drug-induced heart rate variations and rate-dependent QT changes are proportional. Holter ECG allows to study the repolarization in selected RR cycles while controlling environmental rate-related and circadian influences. Repolarization duration was evaluated in 15 normal individuals and 13 patients with stable coronary artery disease and no heart failure who did not differ in terms of 24-hour heart rate, age and sex. The effects of a 3-month treatment with bepridil were assessed in the latter. Using the conventional evaluation through the corrected QT (Bazett formula), no difference was found between the two groups at baseline, and bepridil induced a non-significant 5% prolongation of QTc. At Holter recordings, the QTa (Q-T apex) duration was linearly correlated with the heart rate over 24 hours. To specifically study day-to-night variations and to exclude the rate-dependent and short-term autonomic influences. QTa was studied in populations of averaged QRS-T selected according to i) the last RR cycle length and ii) an identical mean RR interval during the preceding minute. Both RR values were fixed at 800 ms to obtain the "QTa-800" measured directly or extrapolated from linearly correlated, other RR values.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Congenital malformations: care or predict?].

Spectacular scientific and technological advances made in the last decade have had such a profound impact on biological and medical science that they have dramatically modified the citizen's behaviour concerning life events, especially congenital malformation. Prenatal diagnosis (PND) leads to do the diagnosis of almost all fetal internal and external malformations. The matter is, not only to care, but, first to know. The positive efficiency of PND is sometimes preparing the best cares and, of course, to recognize many severe anomalies postnatally diagnosed before PND time, and carrying wellknown 50% rate mortality by neo-natal surgery. Congenital diaphragmatic hernia is pointed out as a good example of it, and of hopes and disappointing in utero foetal surgery. New protocol of assessment of fetal renal function is an appreciated method to do prognosis of some fetal uropathies before late in utero drainage, for a short time waiting for necessary maturation of lungs allowing premature delivery. The possibility to do PND of small and benign malformation leads to ask for the question of utility of to know. In spite of the respect of quality of life, can we really allow this type of human selection to be made? The next knowledges of the human genoma map bring us into the predictive medicine. Using "compulsory" PND is a real risk to practice dangerously, a soft eugenism. PND must be, and remain an outstanding advance to provide better treatment.

Congenital Abnormalities↗
PubMed1991

[Skin sutures in pediatric surgery. Use of a fast-resorption synthetic thread].

Vicryl Rapide is a new, fast absorption skin suture material. Its spontaneous elimination avoids the conventional stitch removal. The tolerability of this material and the cosmetic results obtained were tested in a paediatric surgery department in elective surgery and in emergency surface wound sutures. Provided certain precautions are taken (tense sutures and sutures of the face must be avoided, since the thread passages are visible in 25 percent of the cases), the material is well tolerated; the cosmetic results and child comfort it provides and the absence of stitch removal makes Vicryl Rapide a first-choice material in paediatric surgery.

Child↗