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J B Bouhour

Publications and source records attributed to J B Bouhour.

At least 55 records · Page 3Linked to original sources
PubMed1995

Mapping of a gene for long QT syndrome to chromosome 4q25-27.

Long QT syndrome (LQTS) is a heterogeneous inherited disorder causing syncope and sudden death from ventricular arrhythmias. A first locus for this disorder was mapped to chromosome 11p15.5. However, locus heterogeneity has been demonstrated in several families, and two other loci have recently been located on chromosomes 7q35-36 and 3p21-24. We used linkage analysis to map the locus in a 65-member family in which LQTS was associated with more marked sinus bradycardia than usual, leading to sinus node dysfunction. Linkage to chromosome 11p15.5, 7q35-36, or 3p21-24 was excluded. Positive linkage was obtained for markers located on chromosome 4q25-27. A maximal LOD score of 7.05 was found for marker D4S402. The identification of a fourth locus for LQTS confirms its genetic heterogeneity. Locus 4q25-27 is associated with a peculiar phenotype within the LQTS entity.

Chromosome Mapping↗
PubMed1995

[Clinico-pathological polymorphism of hypertrophic cardiomyopathy in echocardiography].

An echocardiographic Study of 322 adults (age: 40 +/- 16 years), belonging to 20 families with hypertrophic cardiomyopathy (HCM), was undertaken. Affected subjects had a LV diastolic wall thickness > 13 mm. The patients were classified according to the distribution of left ventricular hypertrophy (LVH) and by Maron's classification: 189 subjects were normal, 127 were affected and 6 could not been classified. By Maron's classification: 3% were type I, 33% were type II, 58% were type III and 6% were type IV. LVH was asymmetrical in 95% of cases (septum/posterior wall ratio > 1.3). The familial distribution of LVH of the 4 families in which HCM was genetically related to different loci (chromosome 11, 14 exon 13, 14 exon 8, fifth locus); the LVH was analysed from two short axis LV parasternal views and each plane was divided into 5 segments. The distribution of LVH was said to be identical between two first degree relations when all the same segments were affected, similar when they differed by only 1 or 2 segments and different when they differed by 3 or more segments. In the 26 pairs studied, LVH was identical in 2/26 (8%), similar in 11/26 (42%) and different in 13/26 (50%). Familial HCM usually gives rise to asymmetrical LVH affecting the septum and free wall. An identical distribution in 50% of affected first degree relatives.

Adolescent↗
PubMed1994

[Hypertrophic cardiomyopathy caused by cytochrome-oxidase deficiency].

Mitochondrial cytopathies are due to genetic anomalies in the oxidative phosphorylation enzymes (excepting Krebs cycle, pyruvate and certain other mitochondrial enzymes). Recently discovered, these diseases have a characteristic heterogeneous clinical expression because of the ubiquitous nature of this intracellular organelle. We observed a case in a 16-year-old girl who had cytochrome C oxidase deficiency. The child was born to non-consanguinous parents and had a healthy brother. The first manifestation of the disease was a systolic murmur heard at the age of 4 years. Progressively, exertion dyspnoea, lipothymia with cyanose led to the first echocardiography at 8 years revealing non-obstructive cardiomyopathy. Functional inadaptation of cardiac performance worsened requiring various symptomatic treatments. At the age of 16, the symptomatology included lower limb fatigue and the diagnosis of a metabolic disease was entertained. Phosphorylase A and B activity and phosphokinase activity were normal. High lactic acid levels after exertion suggested a mitochondrial enzyme deficiency. The diagnosis of cytochrome C oxidase deficiency was confirmed by spectrophotometric and polarographic assay of mitochondria from a peripheral muscle biopsy. Treatment with riboflavin, ascorbic acid, factor P, menadione, carnitine and iron sulfate has currently provided some symptomatic improvement. In patients with unexplained cardiomyopathy, the diagnosis of mitochondrial cytopathy should be entertained if oxidoreduction potentials (lactate/pyruvate ratio) are perturbed. The diagnosis is confirmed by enzyme studies of fresh muscle mitochondria. Currently therapeutic prospects are at best very poor. Genetic counselling may be advisable.

Adolescent↗
PubMed1994

Identification of a mutation near a functional site of the beta cardiac myosin heavy chain gene in a family with hypertrophic cardiomyopathy.

Several mutations within the gene coding for the cardiac beta myosin heavy chain (designed MYH7) have been shown to be responsible for Familial Hypertrophic Cardiomyopathy (FHC) in several families, and evidence of genetic heterogeneity has been reported. To investigate the MYH7 gene as the cause of the disease in a small family with FHC, inheritance of the disease and chromosome 14 q11-q12 markers haplotype were studied, exons coding for the head domain of the cardiac beta myosin heavy chain (beta MHC) were analysed for mutations by MDE gel electrophoresis, and sequenced. We report a mutation within exon eight of the MYH7 gene at a very conserved amino acid at position 232, which results in the conversion of an asparagine to serine. This residue Asn-232 is located in a MHC area that has been recently identified as a critical site for ATPase activity. According to recent results on the three-dimensional structure of the myosin head or subfragment-1 (S1), Asn-232 is located in an alpha-helix which forms part of the nucleotide binding pocket. Although this mutation affects an active site, it seems to be associated with a favourable prognosis and a weak penetrance in this family.

Adult↗
PubMed1994

[Demonstration of a fifth locus implicated in familial hypertrophic cardiomyopathies].

Hypertrophic cardiomyopathy is familial in about 50% of cases and is transmitted in the autosomal dominant mode. The first morbid gene implicated in the disease was the gene coding the beta myosin heavy chain (beta MHC) on chromosome 14. However, only 30% of families have this genetic abnormality. Recently, three new loci have been identified on chromosomes 1q3, 11p13-q13 and 15q2. In order to determine whether other genes could be implicated in the disease a linkage analysis study was performed in a West Indian family. The method is based on the analysis of the distribution of the disease in the family and the microsatellite markers. The microsatellites used were those which recognised the 4 loci previously mentioned and 4 new markers situated and arranged with respect to known microsatellites. The results show that in the family studied, the disease did not concord with the markers of the beta MHC gene or with those recognising the loci on chromosomes 1q3, 11p13-q13 and 15q2. There is, therefore, a fifth gene implicated in familial HCM. The heterogeneity of the disease seems even greater than originally thought.

Adult↗
PubMed1993

[Virus and dilated cardiomyopathies].

Dilated cardiomyopathy is so called when an etiological investigation is negative and no cause can be found for ventricular dilatation-hypokinesia. Current research points to genetic, immunological and infectious factors, often associated, and the passage of subclinical viral myocarditis to chronic disease. There is a lot of evidence in favour of this hypothesis. In the experimental model, the relationship between viral myocarditis and dilated cardiomyopathy has been demonstrated with, as cofactors, a genetic predisposition and an immunitary deficiency leading to an auto-immune subacute myocarditis. In the clinical setting, the enterovirus with a high cardiac tropism seems to play an epidemiological role in the genesis of dilated cardiomyopathy. The concentrations of neutralising anti-coxsackie B virus antibodies is higher in subjects with dilated cardiomyopathy than in a control population. The frequency of lymphocytic infiltration, a marker of dysimmunitary myocarditis, is variable from study to study but the presence of sequences of enterovirus genome in the myocardium could explain slow replication of the virus progressively destroying the myocytes. Techniques of molecular hybridization with or without prior genic amplification by the "Polymerase Chain Reaction" have demonstrated such sequences of specific enterovirus genome but discordant results require further studies.

Cardiomyopathy, Hypertrophic↗
PubMed1993

[French familial multicenter survey of hypertrophic cardiomyopathy. Initial Doppler echocardiographic results].

A French multicentre study of hypertrophic cardiomyopathy has recruited 260 subjects belonging to 18 families. At least 3 persons from each family included had a hypertrophic cardiomyopathy. A Doppler echocardiographic examination was performed in all members of these 18 families. The diagnosis of hypertrophic cardiomyopathy was based on M mode and/or 2D observations of parietal hypertrophy: wall thickness over 13 mm. Asymmetrical forms were distinguished from symmetrical forms by a septum/posterior wall ratio of over 1.3 in M mode or 2D study. The patients had an average age of 40 +/- 18 years, 127 were men and 133 women. One hundred and sixty eight were considered to be normal, 87 had hypertrophic cardiomyopathy and 5 were border line. The maximal diastolic wall thickness on M mode recording of pathological cases was 19.2 +/- 4.8 mm compared with 9.5 +/- 1.9 mm in healthy subjects (p < 0.001). The septum/posterior wall ratio was 1.8 +/- 0.62 in pathological cases and 1.1 +/- 0.8 in normal ones (p < 0.001). Eighty five per cent of the cardiomyopathic cases were asymmetrical (74/87) and only 15% were considered to be symmetrical (13/87) on M mode study whereas 5% were concentric on 2D echocardiography. By Maron's classification, type I hypertrophy was observed in 6% of cases (4/64), type II in 30% (19/64), type III in 58% (37/64), and type IV in 6% (4/64). Signs of obstruction were looked for and systolic anterior motion of the mitral valve was observed in 52% of pathological cases (45/86) and mid-systolic aortic valve closure in 30% (25/83).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiomyopathy, Hypertrophic↗
PubMed1993

[Surveillance of iatrogenic complications in a department of cardiology. Thoughts about a preventive strategy].

A study was made of iatrogenic complications (IC) occurring in the department of cardiology of the Nantes Teaching Hospital Group between May 31, 1990 and June 1, 1991. One hundred and fifty eight IC were seen during this period, i.e. an annual incidence of 4.4%. There were 4 deaths following and IC, i.e. an annual mortality rate of 0.11%. Five other IC had serious though non-fatal consequences. Taken in general, IC appeared to be benign and of various origins. Drugs were responsible for almost half of IC and invasive investigations for one third. Application of a simple and single preventive approach is difficult in view of the diversity of causes. The solution lies in part in awareness and education concerning the problem, in which a permanent register system like ours certainly has a role to play.

Adult↗
PubMed1992

[Biological myolysis during combined fenofibrate-pravastatin therapy].

The authors report a case of biological myolysis related to combined fenofibrate-pravastatin therapy in the course of a change in treatment. This case suggests that the risk of myolysis is not specific to the association of some compounds of the two classes but is inherent in possible combinations of drugs from these two families. One must therefore abstain from prescribing these two classes of drugs, since there is no evidence that the combination is preferable to the HMG CoA inhibitor administered alone and the risk of iatrogenic complications is increased. Finally, during the passage from fibrate to HMG CoA reductase a treatment-free interval of about one week should be mandatory.

Angina Pectoris↗
PubMed1992

Detection of enteroviruses in endomyocardial biopsy by molecular approach.

Enteroviruses are considered to be the most common agents implicated in myocarditis and cardiomyopathy. Recent studies have suggested persistent enterovirus infection in chronic disease showing the presence of enteroviral RNA in the myocardium. We used gene amplification by PCR which can demonstrate directly the presence of enteroviral sequences in endomyocardial biopsies. The primers were chosen in the 5' non-coding region of the genome representing highly conserved sequences among enteroviruses and therefore allowed the amplification of the majority of enteroviruses. The hybridization of the amplified products was effected with specific general riboprobe derived from 5' non-coding sequences internal of the amplified fragments. The results include 105 patients distributed in 6 groups: 45 idiopathic dilated cardiomyopathies with 66.7%, 17 alcoholic cardiomyopathies with 52.9%, 10 myocarditis with 30%, 5 multifactorial cardiomyopathies with 40%, 5 patients with immunosuppressive therapy with 100%, and 23 control group without viral etiology with 39.1% positive samples. The study suggested a positive link between viral infection and cardiomyopathies, but did not allow a direct relation between enterovirus infection and idiopathic dilated cardiomyopathy to be established.

Adolescent↗
PubMed1992

[Right atrioventricular metastasis of myxoid liposarcoma. Prolonged course after repeated surgery and chemotherapy].

The authors report a case of cardiac metastasis of a myxoid liposarcoma of the thigh in a 54 year old woman. The treatment associated repeated surgical ablation and chemotherapy. The drugs used induced some cardiotoxicity which limited their prescription but nevertheless, the patient survived 5 years. Previous reported cases do not describe survival lasting more than 2 years and associated chemotherapy would therefore seem to be a valuable adjuvant, increasing the life expectancy of such patients.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

[Prognostic value after 1 year of post-infarction exercise test with measurement of oxygen consumption].

A symptoms-limited exercise stress test with measurement of myocardial oxygen consumption (VO2) was carried out in 56 patients on the 44th +/- 16 days after infarction and in 48 patients on the 119th +/- 31 days. Analysis of the expired gases was performed by mass spectrography, cycle by cycle. The second test was coupled with an exercise gamma-angiography in 40 cases. The parameters on exercise were analysed in two groups at one year: group 1 asymptomatic and group 2 symptomatic (subgroup 2a with angina but no dyspnoea, subgroup 2b with dyspnoea). At the second test, the peak VO2 was lower in group 2 (19.46 +/- 5.78 ml/mn/kg) than in group 1 (24.2 +/- 6.5 ml/mn/kg) (p less than 0.008) irrespective of the symptom (angina and/or dyspnoea). The oxygen pulse was lower in group 2a with angina at one year (42.4% +/- 14.3%) compared with asymptomatic group 1 patient (58.5 +/- 12.4%) (p = 0.03). The 3 parameters: VO2, blood pressure and ejection fraction on exercise were independent. The lack of physical fitness may partially explain the absence of variation of the peak VO2 at the first test. These preliminary results should be confirmed by a multivariate analysis in a larger patient group.

Aged↗
PubMed1991

[A consultation service for the correction of risk factors of atherosclerosis in hospitals].

Although the main risk factors for atherosclerosis have been clearly identified and their correction has demonstrated its efficacy, many subjects do not receive the corrective measures appropriate for their case. The authors describe a hospital service for the prevention of atherosclerosis, which is intended for both primary and secondary prevention as well as for epidemiological monitoring and above all the evaluation of the preventive strategies employed. The results after the service has been running for one year are reported. They appear to confirm the initial options. Cooperation with other people involved in prevention both inside and outside the hospital, is also a fundamental aspect of this task.

Arteriosclerosis↗
PubMed1991

[Cardiovascular complications in chronic atrophic polychondritis. Apropos of an anatomo-clinical case. Review of the literature].

The case of a man, 25 years of age and presenting with chronic atrophic polychondritis (CAP), complicated by a complete atrioventricular block, double mitral valve incompetence and aneurysm of the ascending aorta, offered the possibility of investigating the various clinical manifestations and cardiovascular complications of this common disorder. CAP is a connectivitis of unknown etiology, it corresponds to ubiquitous and recurrent cartilage inflammation, leading to characteristic chondritis of the ears and nose, joint disease and laryngo-trachco-bronchial disorders. Other systemic impact is seen at sites containing high levels of proteoglycans, such as the eye, inner ear and cardiovascular system. Respiratory problems are the main cause of death, but cardiovascular effects occur in 25% of cases and constitute the second most frequent cause of mortality. These effects consist mainly of aortic and/or mitral valve incompetence. Annular dilatation, which is often associated with ectasia of the ascending aorta, is the main cause of aortic incompetence. Several cases of isolated AVB or AVB secondary to Al have been reported. Aneurysms develop along the aorta and the large and medium caliber arteries (sub-clavicular, coronary, mesenteric arteries). These are characterized by destruction of the elastic fibers and a reduction in the proteoglycan content of the walls, which is also observed when dystrophy of the cartilage occurs. Other vascular disorders reported include arteritis of the legs, superficial migratory varices and vascularitis, which in some cases gave rise to skin, renal or neurological reactions.

Adult↗
PubMed1990

Factors predicting mortality in idiopathic dilated cardiomyopathy.

A study of factors predicting mortality was performed in 201 patients with dilated cardiomyopathy (163 men, 38 women, mean age: 48 +/- 11 years) by multivariate analysis (Cox Model) of 51 clinical, electrocardiographic, echocardiographic and haemodynamic parameters, 56 patients died during follow-up (mean follow-up: 57.1 +/- 29.9 months). 5 year survival was 77 +/- 3%. The following parameters were independent predictors of mortality: first symptom: pulmonary oedema, peripheral oedema, syncope; duration of symptoms at the time of inclusion; end systolic left ventricular volume; end diastolic left ventricular diameter; pulmonary artery systolic pressure; and their combination had the most accurate predictive value for death. A quantitative score (s) was calculated and used to define three subgroups: A:s less than or equal to 4.5; B: 4.5 less than s less than 6; C:s greater than or equal to 6. Five-year survival was 90 +/- 5% in group A; 84 +/- 4% in B and only 53 +/- 7% in C. In conclusion, overall survival was good in this population of all stage dilated cardiomyopathy; factors related to clinical severity, left ventricular dilation, systolic pulmonary artery pressure and duration of symptoms defined a subgroup of patients with poor prognosis.

Cardiomyopathy, Dilated↗
PubMed1990

[Cardiomyopathy in the peripartum period: current aspects. A multicenter study. 11 cases].

Eleven of 17 case histories recensed after an inquiry addressed to all the French university hospital cardiological departments were attributed to peripartum cardiomyopathy. Three patients (27%) needed cardiac transplantation. Predisposing factors were multiparity and twin pregnancies. Forty five per cent of patients were under 25 years of age. Hypoproteinemia was present in all serious forms of the condition. Hypoproteinemia, a cardio-thoracic ratio of over 0.60, echocardiographic left ventricular fractional shortening of under 15 per cent and presistance of symptoms after one month of medical treatment were poor prognostic factors. The relatively high incidence of myocarditis (1 out of 11 cases) justifies endomyocardial biopsy.

Adolescent↗