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C Leclercq

Publications and source records attributed to C Leclercq.

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

Development of databases for use in validation studies of probabilistic models of dietary exposure to food chemicals and nutrients.

The data currently available in the European Union in terms of food consumption and of food chemical and nutrient concentration data present many limitations when used for estimating intake. The most refined techniques currently available were used within the European Union FP5 Monte Carlo project to estimate, as accurately as possible, the intake of food additives, pesticide residues and nutrients. Databases of 'true' intakes of food additives (based on brand level food consumption records and additive concentration data), pesticide residues (based on duplicate diet studies) and nutrients (based on biomarker studies) have thus been generated. These kind of estimates are rarely repeatable because the databases generated and used to calculate them require an extraordinary expenditure of time and resources. The databases created served the purpose of estimating as accurately as possible 'true' chemical intakes for assessing the validity of additive, nutrient and pesticide probabilistic models.

Databases, Factual↗
PubMed2003

Probabilistic modelling of human exposure to intense sweeteners in Italian teenagers: validation and sensitivity analysis of a probabilistic model including indicators of market share and brand loyalty.

For the assessment of exposure to food-borne chemicals, the most commonly used methods in the European Union follow a deterministic approach based on conservative assumptions. Over the past few years, to get a more realistic view of exposure to food chemicals, risk managers are getting more interested in the probabilistic approach. Within the EU-funded 'Monte Carlo' project, a stochastic model of exposure to chemical substances from the diet and a computer software program were developed. The aim of this paper was to validate the model with respect to the intake of saccharin from table-top sweeteners and cyclamate from soft drinks by Italian teenagers with the use of the software and to evaluate the impact of the inclusion/exclusion of indicators on market share and brand loyalty through a sensitivity analysis. Data on food consumption and the concentration of sweeteners were collected. A food frequency questionnaire aimed at identifying females who were high consumers of sugar-free soft drinks and/or of table top sweeteners was filled in by 3982 teenagers living in the District of Rome. Moreover, 362 subjects participated in a detailed food survey by recording, at brand level, all foods and beverages ingested over 12 days. Producers were asked to provide the intense sweeteners' concentration of sugar-free products. Results showed that consumer behaviour with respect to brands has an impact on exposure assessments. Only probabilistic models that took into account indicators of market share and brand loyalty met the validation criteria.

Adolescent↗
PubMed2002

Comparative effects of permanent biventricular and right-univentricular pacing in heart failure patients with chronic atrial fibrillation.

BACKGROUND: One third of chronic heart failure patients have major intraventricular conduction and uncoordinated ventricular contraction. Non-controlled studies suggest that biventricular pacing may improve haemodynamics and well-being by reducing ventricular asynchrony. The aim of this trial was to assess the clinical efficacy and safety of this new therapy in patients with chronic atrial fibrillation. METHODS: Fifty nine NYHA class III patients with left ventricular systolic dysfunction, chronic atrial fibrillation, slow ventricular rate necessitating permanent ventricular pacing, and a wide QRS complex (paced width >or=200 ms), were implanted with transvenous biventricular-VVIR pacemakers. This single-blind, randomized, controlled, crossover study compared the patients' parameters, as monitored during two 3-month treatment periods of conventional right-univentricular vs biventricular pacing. The primary end-point was the 6-min walked distance, secondary end-points were peak oxygen uptake, quality-of-life, hospitalizations, patients' preferred study period and mortality. RESULTS: Because of a higher than expected drop-out rate (42%), only 37 patients completed both crossover phases. In the intention-to-treat analysis, we did not observe a significant difference. However, in the patients with effective therapy the mean walked distance increased by 9.3% with biventricular pacing (374+/-108 vs 342+/-103 m in univentricular;P =0.05). Peak oxygen uptake increased by 13% (P=0.04). Hospitalizations decreased by 70% and 85% of the patients preferred the biventricular pacing period (P<0.001). CONCLUSION: As compared with conventional VVIR pacing, effective biventricular pacing seems to improve exercise tolerance in NYHA class III heart failure patients with chronic atrial fibrillation and wide paced-QRS complexes. Further randomized controlled studies are required to definitively validate this therapy in such patients.

Aged↗
PubMed2002

Isolated left main coronary artery stenosis: long term follow up in 106 patients after surgery.

OBJECTIVE: To analyse the long term prognosis in patients with isolated stenoses of the left main coronary artery (LMCA) following surgical revascularisation. PATIENTS: 106 patients (71 men and 35 women, mean age 61 years) were operated on between 1982 and 1998. Before surgery, 103 patients presented with angina pectoris and only 10 had a history of myocardial infarction. Their mean left ventricular ejection fraction was 62%. Stenoses were localised on the LMCA ostium in 19 patients, a subgroup characterised by a high proportion of women (68%). Three patients presented with chronic LMCA occlusion. Forty six patients were operated on as an emergency. The mean (SD) number of grafts per patient was 2.0 (0.5), and only one patient had no left anterior descending (LAD) coronary artery bypass. Bypass of the LAD using the internal thoracic artery was performed in 88 cases. RESULTS: Early postoperative mortality was 4.7% and the five year survival was 86.8%. Late mortality occurred in nine cases, and in three of these it was linked to a coronary condition. Of the 92 long term survivors, 81.5% were totally symptom-free and 77% of those of working age were able to resume work. The postoperative outcome of patients with isolated ostial LMCA stenosis did not differ significantly from that of the other patients. CONCLUSIONS: The postoperative prognosis of isolated LMCA stenosis appears good in terms of mortality and symptoms.

Adult↗
PubMed2002

[MUSTIC trial].

The atrio-bi-ventricular pacing has been used for hemodynamic improvement since 1994, and the MUSTIC trial is the first controlled study assessing this concept. It collected 67 patients with severe and stable heart failure with optimised medical therapy, with sinus rhythm and without any traditional indication for pacing. After two periods of three months with blinded randomisation and cross-over, the bi-ventricular pacing mode showed its superiority to the inactive mode concerning all study endpoints, for example with an improvement of the functional capacity of 23% assessed by the 6-minutes-walk test. Thus the MUSTIC trial opens up the way for morbidity and mortality studies.

Aged↗
PubMed2002

[Medium-term results of multisite biventricular stimulation in severe cardiac failure].

Since its introduction in cardiac failure in 1994, biventricular cardiac stimulation has been widely applied with many clinical trials and the development of new specific technology. The authors present the results observed in the first 125 consecutively implanted patients at the Rennes University Hospital. After a mean follow-up of 22 months, the mortality rate was 40%. The causes of death were sudden death in 42% of patients, progression of cardiac failure in 34% and non-cardiac in 24%. The functional benefits of biventricular cardiac stimulation were seen through significant improvement in HYHA Class, 3.3 +/- 0.5 before implantation to 2.3 +/- 0.8 at the end of follow-up, and by a significant increase of 40% of peak VO2 and of maximal duration of exercise. With the learning curve and development of new technology, the left ventricular catheterisation via a coronary sinus vein, increased from 56% to over 95% during the last two years with an acceptable rate of complications. These results, with the reserve of not being a controlled trial, show the feasibility, safety and efficacy of biventricular cardiac stimulation in terms of functional benefit. Clinical trials are currently underway to assess the impact of this method on morbi-mortality and to assess the concept in association with ventricular defibrillation.

Aged↗
PubMed2002

Coronary subclavian steal syndrome after left internal mammary bypass in a patient with Takayasu's disease.

We report the case of a 56-year-old symptomatic woman who underwent 2 coronary bypasses (left internal mammary artery on the left anterior artery and saphenous venous bypass on the circumflex) for a tight stenosis of the left main coronary. An inflammatory syndrome had been explored for 1 year without specific diagnosis. Eight months later, coronary angiography was performed for recurrence of angina: both bypasses were patent without stenosis and the left main stenosis was unchanged, but significant stenosis of the subclavian artery was found just before the LIMA. The diagnosis of Takayasu's disease was suspected in accordance with the ARC criteria and corticosteroids were started. One year later, because of recurrent angina, the patient was surgically treated with subclavian, vertebral and internal mammary endofibrectomy and an inverted saphenous vein graft from the subclavian to the axillary artery for extensive supra-aortic lesions. The patient remains symptom free at 1 year follow-up.

Female↗
PubMed2001

Effects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delay.

BACKGROUND: One third of patients with chronic heart failure have electrocardiographic evidence of a major intraventricular conduction delay, which may worsen left ventricular systolic dysfunction through asynchronous ventricular contraction. Uncontrolled studies suggest that multisite biventricular pacing improves hemodynamics and well-being by reducing ventricular asynchrony. We assessed the clinical efficacy and safety of this new therapy. METHODS: Sixty-seven patients with severe heart failure (New York Heart Association class III) due to chronic left ventricular systolic dysfunction, with normal sinus rhythm and a duration of the QRS interval of more than 150 msec, received transvenous atriobiventricular pacemakers (with leads in one atrium and each ventricle). This single-blind, randomized, controlled crossover study compared the responses of the patients during two periods: a three-month period of inactive pacing (ventricular inhibited pacing at a basic rate of 40 bpm) and a three-month period of active (atriobiventricular) pacing. The primary end point was the distance walked in six minutes; the secondary end points were the quality of life as measured by questionnaire, peak oxygen consumption, hospitalizations related to heart failure, the patients' treatment preference (active vs. inactive pacing), and the mortality rate. RESULTS: Nine patients were withdrawn from the study before randomization, and 10 failed to complete both study periods. Thus, 48 patients completed both phases of the study. The mean distance walked in six minutes was 22 percent greater with active pacing (399+/-100 m vs. 326+/-134 m, P<0.001), the quality-of-life score improved by 32 percent (P<0.001), peak oxygen uptake increased by 8 percent (P<0.03), hospitalizations were decreased by two thirds (P<0.05), and active pacing was preferred by 85 percent of the patients (P<0.001). CONCLUSIONS: Although it is technically complex, atriobiventricular pacing significantly improves exercise tolerance and quality of life in patients with chronic heart failure and intraventricular conduction delay.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Food composition issues--implications for the development of food-based dietary guidelines.

Sound food composition databases that are both comprehensive and representative of available foods are an essential basic tool to develop Food Based Dietary Guidelines (FBDG). The main drawbacks of current food composition databases available in the European Union are: partial coverage of foods and nutrients, variability of analytical data, lack of accuracy in the description of food items, need for harmonisation of the expression of nutrients. An inappropriate use of these databases could lead to gross errors in the assessment of the nutrient intake levels, in the identification of the major sources of a nutrient, in the comparison of data between countries and in the analysis of time trends. Inadequacy of food composition data is, in part, responsible for the failure to understand some relationships between nutrient intakes and health or disease and for difficulties in establishing quantitative dietary guidelines in terms of nutrients. Recommendations are made for the compilation of future food composition databases and tools are proposed to enhance the quality of existing data. A careful study of the food composition databases is always necessary before nutrition recommendations are given and before trends in nutrient intakes are interpreted.

Data Interpretation, Statistical↗
PubMed2001

Correlation analyses as a step to identify foods that are sources of inter-individual variability in nutrients; their use for the development of food based dietary guidelines.

Food Based Dietary Guidelines (FBDG), in order to be attainable, should take into account the cultural context of the population for which they are developed. They need to focus on foods that actually determine the intake of nutrients for which desirable changes have been identified. Inter-individual variability of nutrient intakes--a measure of the heterogeneity of intakes--is determined by the variability in the consumption of its food sources among the population. The foods that determine a high proportion of inter-individual variability in nutrient intake can be identified on the basis of data banks that describe food and nutrient intakes in the population. The experience accumulated to design Food Frequency Questionnaire through selection of key foods suggests that high quantitative contributors to a specific nutrient may not be important determinants of its intake. On the other hand, the Pearson correlation between the intake of each food source and the total nutrient intake allows quantification of the percentage of variability explained by each item and takes into account the possibility of correlations between different food sources. Once a key food is identified, several strategies are available to modify its intake in the population: through changes in the percentage of consumers/in the mean portion size/in the frequency of intake. The anticipated level of change can be predicted according to the strategy adopted.

Databases, Factual↗
PubMed2001

Responsiveness of the Cochin rheumatoid hand disability scale after surgery.

OBJECTIVE: To assess the responsiveness of the Cochin functional disability scale for the rheumatoid hand after surgery. METHOD: In a prospective study, patients with rheumatoid arthritis (RA) scheduled for surgery of the wrist and/or fingers were evaluated within 48 h before surgery and at least 6 months after surgery. Clinical outcome measures included duration of morning stiffness, total score for tenderness, total score for swelling, visual analogue scale score for pain in the hands and wrists, a score for overall mobility of the wrist and the fingers, grip and pinch strength, the Hand Functional Index (HFI), the Kapandji index and the Cochin scale. Responsiveness was assessed with the paired t-test, the effect size (ES), the standardized response mean (SRM) and the non-parametric Spearman rank correlation coefficient (r(S)). RESULTS: Fifty patients (42 women) were evaluated twice at an interval of 7.16 +/- 2.10 months (mean +/- s.d.) (range 6-15 months). Thirty-six patients (72%) were very satisfied or satisfied with the results of surgery, seven (14%) were not satisfied or dissatisfied and seven (14%) were dissatisfied or very dissatisfied. The Cochin scale score improved at the second visit (P < 0.0001), with SRM and ES values of 0.66 and 0.58 respectively. The correlation of the change in Cochin score with patient overall satisfaction was r(S) = 0.40. Among the impairment measures, grip strength showed the best responsiveness (SRM = - 0.43, ES = - 0.36, correlation with patient overall satisfaction r(S) = 0.46). The change in Kapandji index had the best correlation (r(S) = 0.51) with patient overall satisfaction but its SRM and ES values were low (- 0.19 and - 0.10 respectively). CONCLUSION: The Cochin scale is responsive and appropriate for the assessment of the effects of surgical treatments on disability in RA hands.

Adult↗
PubMed2001

Randomised comparison of coronary stenting with and without balloon predilatation in selected patients.

BACKGROUND: The SWIBAP (stent without balloon predilatation) prospective randomised trial was designed to compare direct coronary stenting with stenting preceded by lesion predilatation with an angioplasty balloon. OBJECTIVE: To determine the feasibility and safety of direct stenting in non-complex coronary lesions in a prospective study. PATIENTS AND DESIGN: All patients < 76 years of age scheduled to undergo angioplasty of a non-complex, non-calcified lesion in a coronary artery of > 3.0 mm, who granted their informed consent, were randomised into the trial. In group I, the stent was placed without balloon predilatation, while in group II stent implantation was preceded by balloon predilatation. The primary end point was the angiographic result according to procedure assigned by randomisation. An intravascular ultrasound substudy was performed in 60 patients. RESULTS: Stent implantation was successful without predilatation in 192 of the 197 group I patients (97.5%), and with predilatation in 197 of the 199 group II patients (99%) (NS). No in-hospital stent thrombosis or death occurred. Overall procedural times, fluoroscopy times, and volumes of contrast agent given (mean (SD)) in group I v group II were 23.50 (13.54) min v 27.96 (15.23) min (p = 0.002), 6.04 (4.13) min v 6.67 (3.65) min (NS), and 135 (65) ml v 157 (62) ml (p < 0.001), respectively. No major adverse cardiovascular events had occurred by 30 days. CONCLUSIONS: The feasibility and safety of direct stenting of selected and non-complex coronary lesions is confirmed. This technique was as successful as the conventional approach and was associated with a minor reduction in fluoroscopic exposure and procedure time and the administration of less contrast agent.

Angioplasty, Balloon, Coronary↗
PubMed2001

Six year experience of transvenous left ventricular lead implantation for permanent biventricular pacing in patients with advanced heart failure: technical aspects.

BACKGROUND: Biventricular pacing has been proposed as an adjuvant to optimal medical treatment in patients with drug refractory heart failure caused by chronic left ventricular systolic dysfunction and intraventricular conduction delay. OBJECTIVE: To assess the technical feasibility and long term results (over six years) of transverse left ventricular pacing with the lead inserted into a tributary vein of the coronary sinus. SUBJECTS: From August 1994 to February 2000, left ventricular lead implantation was attempted in 116 patients who were eligible for biventricular pacing (mean (SD) age 67 (9) years, New York Heart Association (NYHA) functional class III/IV, left ventricular ejection fraction 22 (6)%, QRS duration 185 (26) ms). RESULTS: The overall implantation success rate was 88% (n = 102). A learning curve was indicated by a progressive increase in success from 61% early on to 98% in the last year. The mean pacing threshold was 1.1 (0.7) V/0.5 ms at the time of implantation and increased slightly up to 1.9 (0.9) V/0.5 ms at the end of the follow up period (15 (13) months). The rate of acute and delayed left ventricular lead dislodgement decreased from 30% in the early years to 11% after 1999. During follow up, 19 patients required reoperation for delayed lead dislodgement or increase in left ventricular pacing threshold (n = 15), phrenic nerve stimulation (n = 3), or infection (n = 3). CONCLUSIONS: Transverse left ventricular pacing through the coronary sinus is feasible and safe. The rate of implantation failure and of lead related problems has decreased greatly with increasing experience and with improvements in the equipment.

Aged↗
PubMed2001

[Coronary steal syndrome by systemic pulmonary hypervascularization fed by a mammary-left anterior descending artery bypass. Treatment by embolization].

We report a case of coronary-steal syndrome which occurred after coronary bypass surgery. It was related to systemic hypervascularization of the lung caused by a bronchopathy. The steal syndrome was fed by an ectopic bronchial artery arising from the internal mammary--left anterior descending artery bypass graft. The myocardial ischemia disappeared after hyperselective embolization of the ectopic bronchial artery. The authors outline the rarity of this syndrome and its pathophysiology. They insist on the necessity to perform broncho-systemic arteriography for candidates to coronary surgery, in patients with thoracic diseases which can induce systemic hypervascularization of the lung.

Bronchial Arteries↗
PubMed2001

[Patient information and coronary angiography: experience of the Rennes group].

The object of this study was to assess the degree of patient information of subjects referred for coronary angiography and their reaction to a detailed protocol of information. The enquiry was performed in 3 stages: an oral evaluation of the degree of information with a standardised questionnaire; the giving of written documents from the French Federation and Society of Cardiology mentioning the risks of the procedure; the continuation of the interview with evaluation of the degree of satisfactions with the information provided. Two hundred and thirty one patients referred by cardiologists for non-urgent coronary angiography were interrogated (175 men, 56 women; mean age 63 years, range: 27-83 years). In the 164 subjects who had never had this investigation: 56 (34.1%) did not appreciate the invasive nature of the procedure 111 (67.6%) totally ignored the risks of the procedure 70 (42.6%) were not informed of the possibility of a surgical procedure or of an angioplasty as a result of the procedure. 89% were satisfied with the information concerning the risks of the investigation. In a second group of 100 patients, the comprehension of the information was checked by the same questionnaire used a posteriori. These results show that patient information is very often incomplete. Despite some reticence, the new procedures seem to be globally well accepted but would be more effective if used before hospital admission.

Adult↗
PubMed2000

Comparative effects of permanent biventricular pacing for refractory heart failure in patients with stable sinus rhythm or chronic atrial fibrillation.

This study aimed to compare the long-term benefit of biventricular pacing in drug-refractory heart failure in patients with dilated cardiomyopathy who were in stable sinus rhythm or had persistent atrial fibrillation. The results showed that permanent biventricular pacing in such patients significantly improves exercise tolerance in both groups of patients; however, the benefit tended to be greater in patients with atrial fibrillation.

Aged↗
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↗