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M Komajda

Publications and source records attributed to M Komajda.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Hypertrophic cardiomyopathies].

Hypertrophic cardiomyopathy (CMH) is characterised by hypertrophy of the left ventricle, typically predominantly asymmetric on the interventricular septum. The dreaded complication of the disease is sudden death, especially on physical exertion, and this can constitute the first symptom of the disease. Classified as primary or idiopathic for a long time, there have been considerable recent advances in the molecular genetics which have allowed the physiopathology of the disease to be unveiled. There is great genetic heterogeneity but the different genes have in common a coding for sarcomere proteins. Functional studies suggest that the mutations entail a primary alteration of sarcomere function, with secondary and compensatory hypertrophy. The genetic data equally offer the opportunity to re-evaluate the natural history and the clinical spectrum of the disease. A better understanding of the disease, coming from these molecular data, has allowed a great improvement in the relevance of the information given to patients and their relatives during genetic counselling consultations. The performance of a genetic test with a medical aim can equally be discussed in certain specific situations.

Cardiomyopathy, Hypertrophic↗
PubMed2002

Relation between QT duration and maximal wall thickness in familial hypertrophic cardiomyopathy.

BACKGROUND: QT abnormalities have been reported in left ventricular hypertrophy and hypertrophic cardiomyopathy. OBJECTIVE: To determine the relation between left ventricular hypertrophy and increased QT interval in familial hypertrophic cardiomyopathy. METHODS: The QT interval was measured in 206 genotyped adult subjects with familial hypertrophic cardiomyopathy from 15 unrelated families carrying mutations in the beta myosin heavy chain (beta-MHC) gene (five families, n = 68) or the cardiac myosin binding protein C (MyBPC) gene (10 families, n = 138). Subjects were classified as genetically unaffected (controls, n = 112), affected with left ventricular hypertrophy (penetrants, n = 58), or affected without left ventricular hypertrophy (non-penetrants, n = 36). RESULTS: There was a significant increase in QTmax and QTmin from controls to non-penetrants and penetrants for both the MyBPC group (p < or = 0.001 and p < or = 0.001, respectively) and the beta-MHC group (p < or = 0.001 and p < or = 0.001, respectively). In the MyBPC group, the increase in the QT interval could be explained by increased left ventricular hypertrophy. In the beta-MHC group, non-penetrants had a significantly longer QTmax than controls despite the absence of left ventricular hypertrophy, and a similar QT interval to penetrants despite a lesser degree of left ventricular hypertrophy. CONCLUSIONS: In familial hypertrophic cardiomyopathy, genetically affected subjects without left ventricular hypertrophy may have a prolonged QT duration, which depends not only on the degree of left ventricular hypertrophy, when present, but also on the causative mutation.

Adult↗
PubMed2002

Genetic testing and genetic counselling in hypertrophic cardiomyopathy: the French experience.

AIMS: A major breakthrough in the molecular genetics of hypertrophic cardiomyopathy (HCM) has made genetic testing now available in clinical practice, raising new questions about its implications, potential benefits, and the organisation of the procedure. The aim of this work was (1) to discuss the different questions related to genetic testing in HCM, and propose guidelines for the different situations, (2) to report our preliminary experience with a specific procedure. METHODS AND RESULTS: The main questions asked by patients and relatives concern presymptomatic diagnosis and prenatal counselling/diagnosis, while clinicians sometimes discuss diagnostic and prognostic testing. To take into account the complex medical and psychological implications of this new approach, we developed a specific, multidisciplinary, and multiple step procedure, including a cardiologist, a geneticist, and a psychologist. Seventy subjects were examined, including (1) 29 adults for presymptomatic diagnosis (of whom 10 left the procedure after the first visit and 19 continued, among whom six had a mutation and two experienced negative psychological impact, observed during follow up), (2) nine couples of parents for presymptomatic diagnosis in their children (the procedure was stopped after the first visit in eight and continued in one), (3) 22 couples for prenatal counselling (no prenatal genetic testing was asked for after the first visit), and (4) 10 subjects for diagnostic testing. We decided to perform no prognostic testing. CONCLUSION: Our preliminary experience confirms the complexity of the situation and suggests the necessity for a specific procedure to ensure good practice in genetic testing of HCM.

Adolescent↗
PubMed2002

[Familial hypertrophic cardiomyopathy. French study of the duration and outcome of pregnancy].

Hypertrophic cardiomyopathy (HCM) is a rare, often familial condition, which may be complicated by syncope, atrial or ventricular arrhythmias and episodes of cardiac failure. This genetic disease affects young people and may be observed in women wishing for a pregnancy. The duration and outcome of such pregnancies has not been extensively studied. The authors undertook a retrospective study by questionnaire to compare the pregnancies of 41 women with HCM, a total of 150 pregnancies, with those of 39 unaffected women from the same families: a total of 132 pregnancies. None of the women died, there were no hospital admission for cardiac causes and there was no aggravation of functional status (31% of women with HCM had symptoms before pregnancy compared with 27% during pregnancy). The foetal prognosis was good with no increase in prematurity or neonatal crises. Only the women with symptoms before pregnancy had an increased risk of foetal prematurity compared with healthy women (18% versus 5%). These results indicate the good tolerance of pregnancy of women with HCM and should lead to a revision of systematic medical contra-indication of pregnancy in these patients.

Adult↗
PubMed2002

[Prognostic value of neurohormones in heart failure in clinical practice].

The decisive therapeutic advances achieved in cardiac insufficiency in recent years have been thanks to drugs affecting the different neurohormonal systems in operation. Neurohormonal activation plays a major role in cardiac insufficiency. Several neuro-endocrine mechanisms exert vasoconstrictor effects: the sympathetic system, the renin-angiotensin-aldosterone system and the endothelins. In cardiac insufficiency these effects are counterbalanced, but insufficiently, by vasodilatory agents, mainly the natiuretic peptides, EDRF (endothelium derived relaxing factor), vasodilatory prostaglandins, bradykinin and adrenomedulin. Neurohormonal activation is an excellent marker of not only the severity but also the prognosis of cardiac insufficiency. Standardisation of dosage is desirable in order to allow the use of neurohormonal drugs in a very large number of centres.

Biomarkers↗
PubMed2001

Are we ready for pharmacogenomics in heart failure?

Heart failure is a major health problem and is associated with a high mortality and morbidity. Recently, the role of the genetic background in the onset and development of the disease has been evidenced in both heart failure with and without systolic dysfunction, and in familial and non-familial forms of this condition. Familial forms of dilated cardiomyopathy are more frequent than previously thought. Various modes of inheritance and phenotypes have been reported and this condition appears genetically highly heterogenous. Five genes (dystrophin, cardiac actin, desmin, lamin A/C and delta-sarcoglycan), and additional loci, have been identified in families in which dilated cardiomyopathy is isolated or associated with other cardiac or non-cardiac symptoms. It has been postulated that the molecular defect involved could lead to abnormal interactions between cytoskeletal proteins, responsible either for defect in force transmission or for membrane disruption. More recently, the identification of mutations in genes encoding sarcomeric proteins has led to a second hypothesis in which the disease might also result from a force generation defect. In non-monogenic dilated cardiomyopathy, susceptibility genes (role in the development of the disease) and modifier genes (role in the evolution/prognosis of the disease) have so far been identified. Some data suggest that the efficacy of angiotensin converting enzyme inhibitors, and side-effects, might be related to some genetic polymorphisms, such as the I/D polymorphism of the angiotensin converting enzyme gene. Although preliminary, these data are promising and might be the first step towards application of phamacogenetics in heart failure. This is of paramount importance as the medical treatment of heart failure is characterized by the need for polypharmacy. One of the major challenges of the next millenium, therefore, will be to identify genetic factors which might help define responders to major treatment classes, including angiotensin converting enzyme inhibitors, beta-adrenoreceptor antagonists, angiotensin AT1 receptor antagonists, spironolactone, vasopeptidase inhibitors and endothelin receptor antagonists.

Animals↗
PubMed2001

Thromboembolism in heart failure, old ideas and new challenges.

Until now, the administration of antithrombotic therapy in patients with congestive heart failure has not been well codified. The incidence of thromboembolic complication, such as stroke, peripheral or pulmonary embolism, is regarded as too low to justify the use of anticoagulation in non-selected patients. However, other thrombotic complications may occur especially in patients with ischemic heart failure and represent potential targets for antithrombotic therapy. The objective of this paper is to review the available evidence in the absence of the results of large ongoing trials.

Heart Failure↗
PubMed2001

Ambulatory heart failure management in private practice in France.

UNLABELLED: Management of ambulatory heart failure was assessed in a group of 600 patients, mean age 73, 64% males, NYHA I: 9%; II: 52%; III: 33%; IV: 6%; followed up by a representative sample of private cardiologists. Fifty-two percent of patients had been previously hospitalised for worsening heart failure with a mean duration of stay of 13.1 days, for those hospitalised in the year preceding the survey (26%). First diagnosis of heart failure had been performed by a cardiologist (57%), a general practitioner (37%) or another category of physician (6%). Seventy percent of patients received three or more different classes of heart failure medications. Diuretics were prescribed to 71%, angiotensin converting enzyme inhibitors to 54% and digitalis to 35% of the population. Beta-blockers were given to only 14% of the patients. In patients aged over 80 years, only 45% received angiotensin converting enzyme inhibitors. CONCLUSION: This survey of ambulatory heart failure patients confirms that the disease is predominantly observed in elderly patients, and associated with prolonged and recurrent hospitalisations. The underuse of recommended therapeutic classes including angiotensin converting enzyme inhibitors and beta-blockers deserves further investigation.

Age Distribution↗
PubMed2001

[Observations on the management of cardiac failure in ambulatory patients. Results of a survey of cardiologists].

An enquiry was undertaken amongst 71 cardiologists in 1999 evaluating 600 ambulatory patients with cardiac failure (64% men; mean age 73 years; NYHA Class I: 9%, Class II: 52%, Class III: 33%, Class IV: 6%). Cardiac failure is commoner in men (81%) before the age of 70. After the age of 80, the tendency is inversed (53% of women). Fifty-two per cent of patients had a history of hospital admission for cardiac failure: 26% in the year before the enquiry (on average 13.1 days' hospital stay). On inclusion, the diagnosis was made 4.2 +/- 4.6 years previously and the patients had been followed up for an average of 3.04 +/- 3.3 years. The diagnosis of cardiac failure was made by the cardiologist (57%), the general practitioner (37%), or another category of physician (6%). Eight per cent of patients were treated with a single drug before inclusion, 22% had a bi-therapy and 70% a polytherapy. The most frequently prescribed drugs were: diuretics (71%), angiotensin converting enzyme (ACE) inhibitors (54%) and digitalis (35%). The prescription of betablockers was only reported in 14% of the population. In the over-80's, only 45% of patients were prescribed ACE inhibitors. These results confirm that ambulatory patients with cardiac failure are mainly in NYHA Classes II and III, that the pathology concerns elderly patients and that it is the cause of recurrent hospital admission. The prescription of diuretics is the main therapy in all NYHA Classes. ACE inhibitors were only prescribed in 2/3 of patients and in less than half of patients over 80 years of age. The prescription of betablockers remains marginal. The reason for the underprescription of recommended drugs (International Recommendations) would justify further investigation.

Adrenergic beta-Antagonists↗
PubMed2000

A new locus for autosomal dominant dilated cardiomyopathy identified on chromosome 6q12-q16.

Dilated cardiomyopathy (DCM) is a heart-muscle disease characterized by ventricular dilatation and impaired heart contraction and is heterogeneous both clinically and genetically. To date, 12 candidate disease loci have been described for autosomal dominant DCM. We report the identification of a new locus on chromosome 6q12-16 in a French family with 9 individuals affected by the pure form of autosomal dominant DCM. This locus was found by using a genomewide search after exclusion of all reported disease loci and genes for DCM. The maximum pairwise LOD score was 3.52 at recombination fraction 0.0 for markers D6S1644 and D6S1694. Haplotype construction delineated a region of 16.4 cM between markers D6S1627 and D6S1716. This locus does not overlap with two other disease loci that have been described in nonpure forms of DCM and have been mapped on 6q23-24 and 6q23. The phospholamban, malic enzyme 1-soluble, and laminin-alpha4 genes were excluded as candidate genes, using single-strand conformation polymorphism or linkage analysis.

Adolescent↗
PubMed2000

Prognostic value of neurohormonal activation and cardiopulmonary exercise testing in patients with chronic heart failure.

We compared the value of plasma neurohormones and cardiopulmonary exercise testing for predicting long-term prognosis in patients with moderate congestive heart failure (CHF). We studied 264 consecutive patients with CHF due to left ventricular systolic dysfunction. Plasma atrial natriuretic peptide (ANP), norepinephrine, and endothelin-1 were measured at rest in all patients, who also underwent a symptom-limited maximal exercise with oxygen consumption (VO(2)) determination. After a median follow-up of 789 days, 52 deaths and 31 heart transplantations occurred, of which 4 were urgent. In an univariate analysis, New York Heart Association functional class, systolic blood pressure at rest, left ventricular end-diastolic diameter, left ventricular ejection fraction, peak VO(2), percent of predicted peak VO(2), plasma ANP, plasma norepinephrine, and plasma endothelin-1 were associated with survival without urgent heart transplantation. In a multivariate stepwise regression analysis, only plasma ANP (p = 0.0001), left ventricular ejection fraction (p = 0.007), and plasma norepinephrine (p = 0.035), but neither peak VO(2) nor percentage of predicted peak VO(2), were independent predictors of death or urgent heart transplantation. Determination of plasma ANP and norepinephrine provides additional independent information for long-term prognostic determination compared with exercise testing alone. Measurement of plasma neurohormones should therefore be considered routinely as a complementary or alternative tool for identifying high-risk patients with moderate CHF.

Atrial Natriuretic Factor↗
PubMed2000

Homozygotes for a R869G mutation in the beta -myosin heavy chain gene have a severe form of familial hypertrophic cardiomyopathy.

UNLABELLED: Familial Hypertrophic Cardiomyopathy (FHC) is an autosomal dominant disease characterised by ventricular hypertrophy, with predominant involvement of the interventricular septum. It is a monogenic disease with a high level of genetic heterogeneity (nine genes and more than 110 mutations reported so far). We describe a family with a new R869G mutation in the beta -myosin heavy chain gene (MYH7). This mutation was found in the heterozygous status in both parents and in the homozygous status in the two children. A haplotype analysis on the MYH7 locus with microsatellite markers showed that the same haplotype is transmitted within the family, suggesting a founder effect. Clinically, the father was asymptomatic with mild left ventricular hypertrophy on echocardiography. The mother had a mild form of hypertrophic cardiomyopathy and remained asymptomatic until 60 years old when an atrial fibrillation occurred. For the two children, clinical diagnosis was performed at 12 and 8 years and atrial fibrillation occurred at 17 years. For both children, the evolution was characterized by left ventricle (LV) systolic dysfunction and a severe dilatation of the left atrium before 40 years of age. CONCLUSIONS: In this family, a new R869G mutation in the MYH7 gene was found. Interestingly, a mutation was found at the homozygous status for the first time in FHC. This finding suggests that this particular mutation is compatible with life, but for homozygous subjects, age at onset of symptoms was earlier and the disease much more severe than in the heterozygous subjects, suggesting a gene-dose effect.

Adult↗