PubMed Health⌕ Search

Biomedical subjects

R Isnard

Publications and source records attributed to R Isnard.

71 records · Page 4Linked to original sources
PubMed1992

Cardiomyopathy in Friedreich's ataxia: a Doppler-echocardiographic study.

Heart involvement is frequent in Friedreich's ataxia (FA), the most prevalent of the spino-cerebellar degenerative diseases, which is inherited with an autosomal recessive pattern. However, the pathophysiological link between cardiac and neurological disorders is not yet clearly established. We compared a group of 10 patients with FA to a control group (C) of 16 normal subjects, using Doppler-echocardiography. To see whether cardiac involvement was specific to FA, the data of patients with FA were also compared to those of patients with autosomal dominant olivo-ponto-cerebellar atrophia (OPCA), another spino-cerebellar degenerative disease. There was an increase in left ventricular mass index in FA (154 +/- 9 g.m-2 vs 99 +/- 7 g. m-2 in C, P < 0.001), systolic function was normal, the ejection fraction (EF) slope and E/A ratio were decreased (85 +/- 9 mm.s-1 vs 130 +/- 7 mm.s-1 in C, P < 0.001 and 1.5 +/- 0.1 vs 1.7 +/- 0.1 in C, P < 0.01, respectively), while the isovolumic relaxation period was increased (96 +/- 3 ms vs 92 +/- 2 ms in C, P < 0.01). Deceleration time and time-velocity integrals of A wave to total mitral flow were not modified. In OPCA only the E/A ratio was decreased (1.5 +/- 0.1 vs 1.7 +/- 0.1 in C, P < 0.05). These data show the presence of cardiomyopathy in FA with left ventricular hypertrophy and suggest the presence of diastolic function abnormalities. The cardiomyopathy seems specifically associated with FA and not to spino-cerebellar degenerative disease in general.

Adolescent↗
PubMed1992

Diagnosis of pulmonary embolism by transoesophageal echocardiography.

A 68-year-old woman was admitted for major dyspnoea. A transoesophageal echocardiogram was performed after the occurrence of acute circulatory shock. During the examination, the patient was under mechanical ventilation. We found a thrombus that had almost occluded the right pulmonary artery and which was later confirmed by selective angiography. Despite treatment, the patient died 2 days later; autopsy confirmed the thrombus in the right pulmonary artery.

Aged↗
PubMed1992

[Non invasive evaluation of cardiovascular effects of nebivolol in patients with cardiac insufficiency].

The results of several studies, mostly without controls, have suggested that betablockers, administered at progressively increasing doses, may be beneficial in cardiac failure. Based on this hypothesis, betablockers with a peripheral vasodilator effect, such as Nebivolol, could be particularly valuable in this indication. A preliminary study of its tolerance, haemodynamic and neurohormonal effects was carried out with a noninvasive methodology in 12 patients with cardiac failure in sinus rhythm, 8 men and 4 women (average age 53 +/- 12 years), all of whom had Class III or IV symptoms according to the NYHA Classification. The protocol had 2 phases: the first was an open phase during which Nebivolol was administered at a dose of 1 mg/day for 48 hours then 2.5 mg/day for 72 h. In the second phase, the patients were randomly separated into 2 groups, one to receive placebo and the other 2.5 mg for one week then 5 mg of Nebivolol for the 5 remaining weeks. The heart rate decreased significantly from 70 +/- 3 to 63 +/- 4 beats/min (p < 0.01) with Nebivolol 1 mg/day without further slowing at the 2.5 mg dosage. During the randomised phase, the heart rate remained stable in the Nebivolol group but increased to its initial value in the group given placebo. No aggravation of symptoms was observed in the Nebivolol group. No significant changes in cardiac output, parameters of cardiac loading or contractility could be demonstrated after 6 weeks' treatment. During submaximal exercise testing, plasma concentrations of catecholamines and atrial natriuretic factor tended to be higher with Nebivolol than with placebo.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗
PubMed1992

[Atrial natriuretic factor and cardiac insufficiency].

The atrial natriuretic factor (ANF) is a vasodilating and natriuretic peptide. In experimental and human cardiac failure, plasma ANF concentrations are increased. The ANF is a good marker of functional and haemodynamic severity and of the prognosis of cardiac failure. In this syndrome, messenger RNA of ANF is expressed not only in the atria but also in the ventricles which also secrete the peptide. Attenuation of the natriuretic response is observed in cardiac failure. It may be related to an abnormality situated after the receptor and second messenger, cyclic GMP and/or the reduction of renal perfusion pressure which occurs in cardiac failure. The therapeutic perspectives of ANF in cardiac failure are limited by the necessity of continuous intravenous or parenteral administration. Inhibitors of the enzyme degrading the peptide, neutral endopeptidase, are under evaluation in clinical trials which are at a preliminary stage for the moment.

Atrial Natriuretic Factor↗
PubMed1992

[Androgen insensitivity syndrome. Diagnosis and therapy].

Ten patients with complete or incomplete androgens insensitivity syndrome (A.I.S.) is reported. Diagnosis of A.I.S. is presented on the basis: clinical, phenotype, studies of sexual steroids specially androgens, gonadotropins, 5-alpha-reductase activity and possible abnormality of androgen target cells from the genital skin. Histology of the testes is shown. Surgical treatment of these patients is reported, depending of the abnormality of the genitalia.

Adolescent↗
PubMed1992

[Peripheral calcific embolism after percutaneous mitral valvuloplasty].

The authors report a case of calcific embolization after percutaneous mitral valvuloplasty. The nature of the embolism was confirmed by anatomopathological examination after popliteal embolectomy. This complication would appear to be extremely rare but represents an additional risk in patients with calcific mitral stenosis.

Adult↗
PubMed1992

[Nitrate derivatives and cardiac insufficiency].

Nitrate derivatives are venous vasodilators which are effective in reducing the symptoms of pulmonary congestion. The beneficial action on exercise capacity was recently demonstrated in the Veterans II Study in association with Hydralazine and has also been suggested by other trials. The reduction in mortality from cardiac failure was demonstrated in the Veterans I Study in association with Hydralazine compared to conventional digitalo-diuretic therapy but seems less important than that obtained by angiotensin converting enzyme inhibitors. The phenomenon of tolerance seems to be related to the use of high doses in continuous therapy and may be countered by discontinuous use of the drug during the 24 hour period. Tolerance seems to be related to neuro-hormonal factors and perhaps to depletion of SH groups. Simultaneous use of nitrates and ACE inhibitors seems to be an interesting therapeutic concept.

Aged↗
PubMed1991

Male pseudohermaphroditism due to Leydig cell agenesia and absence of testicular LH receptors.

OBJECTIVE: The aim of our study was to establish the definitive diagnosis in an adult patient with male pseudohermaphroditism in whom testicular feminization syndrome had been suspected at the age of 8, based on genetic, clinical and pathological studies. DESIGN: Hypothalamo-hypophysio-testicular function was assessed in vivo. Androgen mechanism of action and testicular gonadotrophin binding were studied in vitro. PATIENT: At the age of 33 the phenotype was almost completely feminine except for slight clitoral enlargement and posterior labial fusion. Internal genital duct derivatives were masculine except for a short vagina. Both testes were cryptorchid. MEASUREMENTS: LH and FSH were determined pre- and post-gonadectomy. Progesterone, 17-OH-progesterone, androstenedione, dehydroepiandrosterone testosterone (T) and oestradiol were determined basally in peripheral and spermatic blood post-hCG stimulation, and in peripheral blood after orchidectomy. Dihydrotestosterone (DHT) receptors and 5 alpha-reductase activity were determined in genital skin fibroblasts. Receptors for LH and FSH were determined in membrane preparations from both testes. RESULTS: LH was high (31 IU/l) and FSH (8 IU/ml) normal. T or steroid precursors were detected basally or after hCG stimulation in peripheral blood showing absence of testicular production. Spermatic venous blood steroid concentrations were consistent with slight T production, in accordance with testis histology which showed few Leydig-like cells among fibroblasts in the interstitial space. DHT specific binding capacity and affinity and 5 alpha-reductase activity were normal in genital skin fibroblasts. Gonadotrophin binding studies in testicular membranes confirmed the absence of LH specific binding, whereas FSH binding was higher than normal when expressed per mg of protein (27.0 vs 9.4 +/- 0.6 fmol/mg protein in controls), and lower than normal in both testes since patient's testicular weights were abnormally low. CONCLUSIONS: The patient was considered to have an almost complete form of Leydig cell agenesia/hypoplasia in which absence of specific LH binding correlated with total absence of differentiated Leydig cells and insensitivity of undifferentiated interstitial cells to LH stimulation.

Adult↗
PubMed1991

[Search for emboligenic heart disease in case of ischemic cerebral accidents].

The demonstration of a cardiac source of systemic embolism in patients who have suffered a cerebral ischemic event may have important therapeutic implications. This explains the large demand for echocardiography and Holter monitoring in these patients. The frequency of cerebral embolism of cardiac origin, the simplification of the diagnostic approach by non-invasive investigations and the precision of ultrasound techniques explains the tendency towards the indiscriminate generalisation of this attitude. However, the large number of potential patients for investigation, the limited facilities of investigation and the incertitude over the responsibility of certain cardiac abnormalities with respect to the context and age, are arguments in favour of a more selective investigative approach. The keystone of diagnosis is careful history taking and clinical examination with interpretation of the ECG and chest X-ray. Three clinical situations may then be identified: 1) A cardiac abnormality known to be highly embolic is diagnosed from the outset (e.g. mitral stenosis, valve prosthesis, endocarditis, myocardial infarction). The diagnostic work-up is no longer etiological: echocardiography may show intracardiac thrombi or a valvular vegetation, reinforcing the causal relationship, but the complementary investigations are mainly useful for evaluation the cardiac disease and for deciding on curative or preventive therapy. 2) A cardiac abnormality is diagnosed but its responsibility is doubtful due to its high prevalence and low embolic potential. This is the case of patients with mitral valve prolapse, mitral annular calcification, calcific aortic stenosis and VVI pacing. Complementary investigations are not discriminative for the etiological diagnosis of the cerebral embolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmias, Cardiac↗
PubMed1990

[Tolerance of treatment with nitrate derivatives].

Tolerance to treatment with nitrate derivatives, suspected for many years and often ignored in everyday clinical practice, has recently been the subject of much study. Although the phenomenon has been clearly demonstrated in patients on long-term therapy, it seems to vary from patient to patient, with the underlying pathology and the galenic form of nitrate used. The mechanism of tolerance to nitrates is multifactorial, related on the one hand to depletion of sulfhydryl groups in the body and on the other to activation of the sympathetic and renin-angiotensin systems. The administration of sulfhydryl groups in the form of N-acetylcysteine partially restores the effects of nitrates in some patients.

Administration, Cutaneous↗
PubMed1990

[Blood flow and compliance of great arterial trunks].

The important technical advances in the last few years in the field of ultrasonic imaging and Doppler velocimetry now enable an accurate evaluation of the vasomotricity, blood flow and compliance of the large peripheral arteries. The information provided by these new non-invasive techniques in clinical pharmacology is considerable as they make possible repeated measurements of different parameters of regional circulation (diameters, flow, pulse wave velocity and modulus of elasticity) and the assessment of the efforts of different vasoactive drugs on these values. Some limitations are nevertheless inherent to the non-invasive nature of the examination.

Arteries↗
PubMed1988

[Effects of beta-blockers on hemodynamics of the forearm after tobacco stimulation].

In mild hypertension, a betablocker treatment could reduce cardiovascular events. But in smoking men the benefit disappears and this interaction is unexplained. In 6 healthy non smoking men, we studied the effects of acute oral administration of propranolol (80 mg) pindolol (15 mg) and placebo after cigarette smoking (CS) (two cigarettes within 10 minutes). In a double blind cross over randomized study, arterial pressure and heart rate (HR) were recorded within 20 minutes after CS. Brachial artery diameter (D), Local vascular Resistance (RL), Local arterial Compliance (CL) and pulse wave velocity (VOP) were determined non invasively (using a pulsed doppler system) before and 20 mn after CS. Under placebo, mean arterial pressure (PAM), HR and RL increased significantly after CS (+9.2 +/- 3 mmHg, +4.5 +/- 3 b/mn and +36 +/- 14 per cent, respectively). These modifications were not different after propranolol, pindolol or placebo (ANOVA). Arterial distensibility (CL) was decreased after CS and this alteration was not prevented by beta-blockers. Brachial artery diameter was not modified after CS. Our results demonstrate that acute treatment with non selective beta-blockers with or without sympathomimetic intrinsic activity does not prevent haemodynamic modifications induced by cigarette smoking.

Adrenergic beta-Antagonists↗
PubMedDate not supplied

[Medical treatment of sustained ventricular tachycardia. Retrospective study of 85 patients].

In this retrospective study the antiarrhythmic of 85 patients suffering from sustained and recurrent attacks of ventricular tachycardia is analysed. Among these patients, 48 had ischaemic heart disease, 18 had right ventricular arrhythmogenic dysplasia, 9 had dilated cardiomyopathy and 2 had complex heart disease; in 8 patients the tachycardia was idiopathic. Two hundred and seventy-two antiarrhythmic treatments administered orally alone or in combination were studied. Their effectiveness was evaluated on the clinical course of the disease, on the résults of Holter recordings and, in some cases, on electrophysiological exploration. The mean follow-up period was 50 months. Each patient received 3.2 antiarrhythmic treatments on average. The effectiveness and side-effects of these treatments are analysed retrospectively, but the relative effectiveness of a treatment compared to another cannot be extrapolated to a new patient. Prescription in this field is purely empirical. The recent amiodarone-flecainide combination has been the most frequently used antiarrhythmic treatment in recent years. It was given to 33 patients in this series and proved effective in 21 patients followed up for 22 months.

Adolescent↗