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Emmanuel Roux

Publications and source records attributed to Emmanuel Roux.

11 recordsLinked to original sources
PubMed2006

Linking clinical measurements and kinematic gait patterns of toe-walking using fuzzy decision trees.

Toe-walking is one of the most prevalent gait deviations and has been linked to many diseases. Three major ankle kinematic patterns have been identified in toe-walkers, but the relationships between the causes of toe-walking and these patterns remain unknown. This study aims to identify these relationships. Clearly, such knowledge would increase our understanding of this gait deviation, and could help clinicians plan treatment. The large quantity of data provided by gait analysis often makes interpretation a difficult task. Artificial intelligence techniques were used in this study to facilitate interpretation as well as to decrease subjective interpretation. Of the 716 limbs evaluated, 240 showed signs of toe-walking and met inclusion criteria. The ankle kinematic pattern of the evaluated limbs during gait was assigned to one of three toe-walking pattern groups to build the training data set. Toe-walker clinical measurements (range of movement, muscle spasticity and muscle strength) were coded in fuzzy modalities, and fuzzy decision trees were induced to create intelligible rules allowing toe-walkers to be assigned to one of the three groups. A stratified 10-fold cross validation situated the classification accuracy at 81%. Twelve rules depicting the causes of toe-walking were selected, discussed and characterized using kinematic, kinetic and EMG charts. This study proposes an original approach to linking the possible causes of toe-walking with gait patterns.

Biomechanical Phenomena↗
PubMed2006

A support method for the contextual interpretation of biomechanical data.

In the clinical field, biomechanical data provided by advanced technical devices are still underexploited. Data analysis usually consists of extracting attributes or computing synthetic values from temporal data and exploiting them by means of a monovariable statistical method. This article proposes a method to support clinicians, especially those in orthopedics, in the contextual interpretation of biomechanical data. We propose to characterize temporal biomechanical data by means of fuzzy space-time windows and to induce fuzzy decision trees to map the biomechanical and clinical data related to patients. Then, we present a method for objectively explaining a given clinical characteristic of a particular patient; this method is derived using the fuzzy rule base generated from the trees and a satisfiability measure. We have applied our method to real data in order to provide an objective explanation of the subjective self-evaluation of the functional status of patients with a shoulder prosthesis, and evaluate it by means of the stratified tenfold cross validation method. The mean explanation rate--which corresponds to the mean proportion of the patients belonging to test sets whose functional state is explained by the proposed method--exceeds 80% for more than half of the decision trees, and exceeds 70% for 94% of the trees. By supporting clinicians during the biomechanical data interpretation process, our method helps them take the objective biomechanical measurements in the medical practice into account, particularly in orthopedics. It can also make subjective evaluations more objective by mapping subjective and objective data.

Algorithms↗
PubMed2006

Accuracy of tissue Doppler echocardiography in the diagnosis of new-onset congestive heart failure in patients with levels of B-type natriuretic peptide in the midrange and normal left ventricular ejection fraction.

BACKGROUND: Based on the hypothesis that it reflects left ventricular (LV) diastolic pressures, B-type natriuretic peptide (BNP) is largely utilized as first-line diagnostic complement in the emergency diagnosis of congestive heart failure (HF). The incremental diagnostic value of tissue Doppler echocardiography, a reliable noninvasive estimate of LV filling pressures, has been reported in patients with preserved LV ejection fraction and discrepancy between BNP levels and the clinical judgment, however, its clinical validity in such patients in the presence of BNP concentrations in the midrange, which may reflect intermediate, nondiagnostic levels of LV filling pressures, is unknown. METHODS: 34 patients without history of HF, presenting with acute dyspnea at rest, BNP levels of 100-400 pg/ml and normal LV ejection fraction were prospectively enrolled (17 with congestive HF and 17 with noncardiac cause). Tissue Doppler echocardiography was performed within 3 hours after admission. RESULTS: Unlike BNP (P = 0.78), Boston criteria (P = 0.0129), radiographic pulmonary edema (P = 0.0036) and average E/Ea ratio (P = 0.0032) were predictive of congestive HF by logistic regression analysis. In this clinical setting, radiographic pulmonary edema had a positive predictive value of 80% in the diagnosis of congestive HF. In patients without evidence of radiographic pulmonary edema, average E/Ea > 10 was a powerful predictor of congestive HF (area under the ROC curve of 0.886, P < 0.001, sensitivity 100% and specificity 78.6%). CONCLUSION: By better reflecting LV filling pressures, bedside tissue Doppler echocardiography accurately differentiates congestive HF from noncardiac cause in dyspneic patients with intermediate, nondiagnostic BNP levels and normal LV ejection fraction.

Aged↗
PubMed2005

Comparative accuracy of color M-mode and tissue Doppler echocardiography in the emergency diagnosis of congestive heart failure in chronic hypertensive patients with normal left ventricular ejection fraction.

The accuracy of the tissue Doppler E/Ea and color M-mode Doppler E/Vp indexes in diagnosing congestive heart failure (HF) was investigated in 20 chronic hypertensive patients with acute dyspnea and normal left ventricular ejection fractions who met Vasan's criteria for definite diastolic HF, compared with 20 gender- and age-matched hypertensive patients with noncardiac cause of acute dyspnea. The E/Ea ratio appeared to be more reproducible (variability 4% to 9% vs 6 to 14%) and more precise (sensitivity 77.8%, specificity 100%, and accuracy 89.5% for the optimal cutoff of 11 vs sensitivity 73.7%, specificity 75%, and accuracy 74.3% for the optimal cutoff of 1.5) than the E/Vp ratio in this clinical setting.

Aged↗
PubMed2005

B-type natriuretic peptide and tissue Doppler study findings in elderly patients hospitalized for acute diastolic heart failure.

The imbalance of Starling's forces was investigated in 25 elderly patients hospitalized for acute diastolic heart failure. Tissue Doppler evidence of elevated left ventricular filling pressures was present on admission in 17 patients with high B-type natriuretic peptide (BNP) levels. Serum proteins concentrations and colloid osmotic pressure, related to malnutrition and severe sepsis, were significantly less in the 8 patients without tissue Doppler evidence of elevated filling pressures, and a high level of BNP was consistent with paroxysmal elevation in filling pressures in this setting.

Acute Disease↗
PubMed2005

Evaluation of statistical association measures for the automatic signal generation in pharmacovigilance.

Pharmacovigilance aims at detecting the adverse effects of marketed drugs. It is generally based on the spontaneous reporting of events thought to be the adverse effects of drugs. Spontaneous Reporting Systems (SRSs) supply huge databases that pharmacovigilance experts cannot exhaustively exploit without data mining tools. Data mining methods; i.e., statistical association measures in conjunction with signal generation criteria, have been proposed in the literature but there is no consensus regarding their applicability and efficiency, especially since such methods are difficult to evaluate on the basis of actual data. The objective of this paper is to evaluate association measures on simulated datasets obtained with SRS modeling. We compared association measures using the percentage of false positive signals among a given number of the most highly ranked drug-event combinations according to the values of the association measures. By considering 150 drugs and 100 adverse events, these percentages of false positives, among the 500 most highly ranked drug-event couples, vary from 1.1% to 53.4% (averages over 1000 simulated datasets). As the measures led to very different results, we could identify which measures appeared to be the most relevant for pharmacovigilance.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

Accuracy of tissue Doppler echocardiography in the emergency diagnosis of decompensated heart failure with preserved left ventricular systolic function: comparison with B-type natriuretic peptide measurement.

BACKGROUND: Tissue Doppler echocardiography provides a reliable noninvasive estimation of left ventricular (LV) filling pressures irrespective of LV ejection fraction. However, the diagnostic accuracy of E/Ea ratio has not been adequately determined in patients with suspected heart failure (HF) with preserved LV systolic function in the acute care setting. OBJECTIVE: To investigate the accuracy of E/Ea ratio in the emergency diagnosis of decompensated HF with preserved LV systolic function. METHODS: Seventy patients with a LV ejection fraction >or=45%, 32 with decompensated HF (77 +/- 12 years of age), and 38 with noncardiac cause of acute dyspnea (74 +/- 12) were enrolled. B-type natriuretic peptide (BNP) was measured on admission; lateral, septal and average E/Ea ratios were calculated within 24 hours. RESULTS: Using receiver-operating characteristic curves to evaluate diagnostic performance, BNP (AUC of 0.875, P < 0.0001) and E/Ea ratios (AUC of 0.90-0.92, P < 0.0001) provided similar accuracy for predicting decompensated HF. Optimal cutoffs were 146 pg/ml for BNP (sensitivity and specificity of 90.6% and 76.3%), 9.8 for lateral E/Ea (83.3% and 88.9%), 12.7 for septal E/Ea (76.7% and 91.4%), and 11.5 for average E/Ea ratio (80% and 94.3%). On multivariate logistic regression analysis, average E/Ea ratio yielded independent additional information to a model based on the clinical judgment and BNP level according to the standard cutoff of 100 pg/ml. CONCLUSIONS: Tissue Doppler echocardiography is accurate for predicting decompensated HF with preserved LV systolic function and may be used as a diagnostic complement to inconclusive BNP level in this setting.

Acute Disease↗
PubMed2005

Trends in spontaneous adverse drug reaction reports to the French pharmacovigilance system (1986-2001).

BACKGROUND: The French pharmacovigilance system is based on a network of 31 regional centres located in teaching hospitals and coordinated by the French Medicines Agency ("Agence Française de Sécurité Sanitaire des Produits de Santé" [Afssaps]). Since 1984, they have shared a common database of adverse drug reactions (ADRs) that are spontaneously reported by healthcare professionals. The objective of this study is to describe the characteristics of the reports and the reporting trends in the French pharmacovigilance spontaneous reporting database from 1986 to 2001. METHODS: All the reports from January 1986 to December 2001 were included. Drugs and ADRs were translated to anatomical therapeutic chemical (ATC) codes and MedDRA classifications, respectively. RESULTS: The total number of reports was 197 580 over the 16-year period, with linearly increase over time. The median (interquartile range [IQR]) age of the patients was 53 (34-70) and the male/female ratio was 0.82. The median (IQR) time between the date of occurrence of the ADR and the date of report was 73 days (34-166). The reporter was a specialist in 74% of the reports and a general practitioner in 17%. The annual rate of reporting according to medical demography strongly increased for the specialists, especially since 1994. At least one ADR was considered as serious in 44.8% of the reports. The ADRs were most frequently related to nervous system drugs (23%), followed by cardiovascular drugs (19%) and systemic anti-infectives (17%). The latter class had the fastest progression mostly due to antiretroviral therapy since 1996. According to the Medical Dictionary for Regulatory Activities (MedDRA) coding, the system organ most often reported was skin and subcutaneous tissue disorders (29%), followed by nervous system disorders (19%), gastrointestinal disorders (12%), blood and lymphatic system disorders (12%), vascular disorders (12%) and general disorders and administration site conditions (12%). DISCUSSION: All spontaneous reporting systems are affected by under-reporting. One of their goals is to generate early signals, which might be more affected by reporting bias than by under-reporting. Some improvements should be made in the design of the French database, but data collected since 1986 constitute an essential tool for the routine work of the 31 pharmacovigilance centres. CONCLUSION: This first description of the data of the French pharmacovigilance database involving all drugs and ADRs shows an increasing tendency to reporting over time, especially in specialists and for systemic anti-infective drugs. The database that uses hierarchical international classifications for drugs and adverse reactions may be used for further studies and could be the basis for an automatic signal generation system.

Adult↗
PubMed2004

Prevalence of angiographic coronary artery disease in patients hospitalized for acute diastolic heart failure without clinical and electrocardiographic evidence of myocardial ischemia on admission.

The prevalence of coronary artery disease was investigated in 18 patients hospitalized for acute diastolic heart failure without clinical and electrocardiographic evidence of myocardial ischemia on admission. On the basis of coronary angiography, 7 patients had coronary artery disease and 4 had ischemic heart disease. In addition, besides uncontrolled hypertension and several systemic factors, silent myocardial ischemia potentially contributed to acute exacerbation of heart failure for at least 5 patients with coronary artery disease, according to either elevation in troponin I or segmental wall motion abnormalities.

Aged↗
PubMed2004

Potentials and limitations of color M-Mode and tissue Doppler indexes in identifying pseudonormal mitral filling pattern in patients with acute symptoms of heart failure and preserved left ventricular systolic function.

The aim of this study was to assess the accuracy of flow propagation velocity by color M-mode (Vp) and peak early diastolic mitral annulus velocity by tissue Doppler (Ea) in identifying pseudonormal mitral filling in 25 patients with acute symptoms of heart failure and preserved left ventricular systolic function compared with 25 gender- and age-matched healthy subjects. Although normal velocities for both Vp and Ea were found in 40% of patients, E/Vp and E/Ea ratios were able to differentiate pseudonormal from normal filling irrespective of values for Vp and Ea.

Aged↗