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H Boccalon

Publications and source records attributed to H Boccalon.

At least 37 records · Page 2Linked to original sources

[Teaching targets in vascular medicine].

The reference list presented here is a selection of educative objectives performed by the French "Collège des Enseignants de Médecine Vasculaire" for the different levels of the medical initial education course. It was produced through a collective procedure, after selecting the most relevant topics and setting up writing rules based upon docimology, and favoring practical rather than theoretical objectives. The main topics are peripheral obstructive arterial disease, polyatherosclerosis, atherosclerosis risk factors, venous thromboembolic disease, thrombophilia, chronic venous insufficiency, lymphatic insufficiency, leg ulcers, vascular acrosyndromes, cerebrovascular diseases and connective tissue diseases, vascular occupational diseases, vascular adverse effects of drugs, diabetic vascular disease, the vascular consequences of hypertension, vascular malformations and angiodysplasia, inflammatory arterial diseases, and vascular explorations. As a whole they include about 300 objectives for the five teaching levels. We hope that this list will help stimulate production of training courses and documents strongly needed in this field.

Education, Medical↗

[Assessment of the prevalence of atherosclerotic lower limb arteriopathy in France as a systolic index in a vascular risk population].

OBJECTIVE: Obliterative arteriopathy of the lower limbs is a severe disease. History taking often underestimates prevalence. In studies using the Rose questionnaire and examining the prevalence of symptomatic arteriopathy defined by the presence of intermittent claudication, prevalence has been rather constant, around 2% in the general population in industrialized countries. A more clinical approach searching for physical anomalies (absence of distal pulse) generally gives higher rates. The most recent data led us to conduct a study focusing on screening for arterial disease using the systolic index (the systolic index is the ratio between the ankle and humeral systolic pressure). A systolic index below 0.90 would be a sign of defective perfusion, increasing in severity with poorly compensated arterial lesions. METHOD: A survey was performed in a random sample of 150 practitioners using an allocation procedure to the nearest colleague in case of refusal. A data sheet containing demographic data and the main risk factors was established for each consulting patient aged from 40 to 80 years. The systolic index was measured in each patient with at least one vascular risk or who consulted for pain in the lower limbs. A simple sequential non-randomized patient recruitment scheme was used. RESULTS: The survey population included nearly 9,000 patients (8,987), 46% men and 54% women, mean age 64 years (table I). Patient risk factors including smoking, diabetes, hypertension, and physical exercise were adjusted for sex and age (table II-VI, IX). The systolic index was recorded in 41% of the population who had a vascular risk factor. Among these patients, nearly one-fourth had a systolic index under 0.90, giving a prevalence in the sample population of 11% (table VII). This rate was also assessed by age and sex (table VIII). Logistic regression evidenced a prognostic value (fig. 1) for smoking, hypertension and sedentary activity, and to a lesser extent, for age and sex. There was a significant difference by latitude, patients living in northern France having a higher risk than those living in southern France (table X). In addition, there was a relationship between the systolic index and spontaneous complaint, showing that this complaint is poorly specific for arterial disease (table XI, XII). CONCLUSION: This epidemiological approach to arteriopathy implemented by general practitioners searching for patients with a vascular profile and measuring systolic index is a novel method. It gave an estimation of prevalence at 11% in the French population, a rate compatible with that reported by other international teams. The method also allowed an analysis of factors affecting the rate.

Adult↗

[Intermittent claudication and quality of life. Psychometric validation of the French version of the CLAU-S questionnaire].

CLAU-S is a disease-specific quality of life (QoL) scale for patients with intermittent claudication due to peripheral arterial disease of the lower limbs. Initially developed in Germany, the scale has been translated into French according to classical forward/backward methodology. The objective of this study was to test the validity of the French version of CLAU-S. In its current format, the CLAU-S scale evaluates 5 dimensions: "Daily Living"; "Pain"; "Social Life"; "Disease-specific anxiety"; and "Mood", for a total of 47 items. The QoL scores and clinical findings in 157 patients with intermittent claudication were analysed. Validation of the convergence and discriminatory power of the scale were confirmed. Analysis of structural validity showed grouping of items in accordance with initial scale construction and a clear separation between the different dimensions. Analysis of the internal reliability of the questionnaire confirmed the good internal coherence of these dimensions. Reproducibility of the scores over time was confirmed by test-retest analysis. In addition to the actual validation of CLAU-S, a new, innovative mathematical technique called Structural Modelling Equations was used on this QoL instrument. It related the causal structure of the QoL components in peripheral arterial disease of the lower limbs (stage 2). An indisputable causal relationship was demonstrated between clinical parameters, particularly walking distance, and the QoL components. The classical symptom-deficit-disability causal structure of disease- specific QoL questionnaires was also studied. In particular, we found an essential relationship between the Daily Living dimension and, to a lesser extent, the Social Life activities and Disease- specific anxiety dimension, and QoL. The Pain dimension proved to be an explanatory variable of the other QoL components without being directly related to QoL. Finally, the Mood dimension was a resultant variable of QoL and not an explanatory variable of QoL. This study therefore enabled validation of the psychometric properties of the French version of CLAU-S and also demonstrated the complementary roles of walking distance and QoL in the management of patients with intermittent claudication.

Activities of Daily Living↗

A clinical approach to the management of the patient with coronary (Co) and/or carotid (Ca) artery disease who presents with leg ischaemia (Lis).

The purpose of this document is to provide the clinician with easy-to-use guidelines when faced with a patient with severe ischaemia in the limbs requiring interventional treatment; the CoCaLis document does not focus on the management of the lower limb ischaemia, but rather on the best possible approach to the associated coronary and/or carotid artery disease. The first part of the text deals with the epidemiological aspects of this condition followed by a description of, and proposals for, the management of risk factors. The next part deals with the approach to the coronary circulation and the carotid territory. In each part attention is mainly given to the practical aspects in terms of both diagnosis and treatment; for each of these steps the costs involved are considered and attention given to balancing the clinical decisions against the costs. The recommendations given are 'evidence based' when such evidence exists and, if not, the proposals are based on the consensus of the members of the group. In many instances it was apparent that the necessary information is not available in the literature. The authors hope that the CoCaLis document may not only improve the management of the vascular patient but also stimulate further research in this difficult clinical condition which carries a significantly increased risk for the patient.

Angioplasty, Balloon, Coronary↗

[Contraindicated medical references and vasoactive agents in arterial pathology of the lower limbs].

INTRODUCTION: Treatment of arteriopathy of the lower limbs (ALL) with vasoactive drugs must follow French health laws recently introduced in regard to the prescription of unuseful drugs and treatments and the frequency at which some patients resort to specific drugs and treatments. Prescription of vasoactive drugs in ALL requires the existence of functional discomfort. Prescription of only one vasoactive drug is sufficient. CURRENT KNOWLEDGE AND KEY POINTS: Results of published clinical trials demonstrate the efficacy of vasoactive drugs for the relief of claudication related to arteriopathy. To conform to the rules of the European Drug Agency, treatment with vasoactive drugs which improve the walking distance is recommended as "symptomatic treatment of arterial claudication in ALL". Iloprost is only used in the treatment of permanent ischemia. Prescription of vasoactive drugs is part of a scheme of therapeutic indications that are well known and rigorous. Rules of hygiene and reduction of risk factors are the essential preliminary elements. In the case of arterial claudication due to femoral or distal obliteration, chemical medication is suggested, whereas in the case of iliac lesion, angioplasty should be considered. FUTURE PROSPECTS AND PROJECTS: Walking is recommended in all the cases; however, usually less than a quarter of all patients will conform to this recommendation. Vasoactive drugs thus find their place in the therapeutic scheme. Evaluation of the efficiency of vasoactive drugs rises above simple measures of the walking distance, rather integrating quality of life and usefulness of the treatment.

Angioplasty↗

[Chronic obliterative arterial disease of the lower limbs in the coronary patient: prevalence and prognostic incidence. The Monica Toulouse register].

PURPOSE: This study was aimed at evaluating the prevalence of peripheral arterial disease of the lower extremities and its prognostic value in a population of patients from the Haute-Garonne department, who were hospitalized for acute coronary artery disease. METHODS: Between 1985 and 1991, four thousands three hundred and sixty-eight patients (3,680 males and 688 females) presenting with acute coronary artery disease were included in the study. RESULTS: The prevalence of peripheral arterial disease of the lower extremities was 13.4%, increasing with age and being higher in male patients. In regard to patients hospitalized for acute myocardial infarction (n = 2,417), independent relationships were observed between the 28-day mortality and the following: patient's age (odds ratio: 1.02; 95% confidence interval: 1.01-1.04; P < 0.0005), female gender (odds ratio: 1.32; 95% confidence interval: 1.17-1.54; P < 0.002), inclusion in the study (odds ratio 0.95; 95% confidence interval: 0.90-0.99; P < 0.02), previous coronary artery disease (odds ratio: 2.88; 95% confidence interval: 2.32-3.48; P < 0.0001), and peripheral arterial disease (odds ratio: 1.61; 95% confidence interval: 1.26-2.06; P < 0.0001). CONCLUSION: The prevalence of peripheral arterial disease of the lower extremities is high in patients with acute coronary artery disease in both genders, whatever the age. This disease is therefore an independent marker of mortality for acute myocardial infarction. Easy diagnosis of peripheral arterial disease of the lower limbs by measurement of the ankle pressure index allows identification of patients prone to death from acute myocardial infarction.

Adult↗

Carotid intima-media thickness and coronary heart disease risk factors in a low-risk population.

OBJECTIVE: Coronary heart disease (CHD) risk factors have been consistently related to an increase in carotid intima-media thickness (IMT) in selected populations. However, few studies were population-based and furthermore little attention has been given to the influence of CHD risk factors on IMT in low-risk populations for CHD. DESIGN: We examined the association between carotid IMT and CHD risk factors in a large (n = 1013) and representative sample of middle-aged men and women in one of the European populations with the lowest CHD risk. METHODS: High-resolution B-mode ultrasonography of the common carotid arteries was performed. RESULTS: Age, smoking (not significant in women), body mass index, waist to hip ratio, systolic (SBP) and diastolic blood pressure, alcohol consumption, total and low-density lipoprotein cholesterol, triglycerides, glycaemia, fibrinogen (not significant in women), haematocrit (not significant in men) and insulin (not significant in women) were positively and significantly associated with mean IMT. High-density lipoprotein (HDL) cholesterol (not significant in women) was negatively and significantly associated with mean IMT. In a subsample of 355 men, IMT was not associated with angiotensin I-converting enzyme gene polymorphism. Multivariate analyses showed, in men, independent associations between mean IMT (0.61+/-0.11 mm) and age, pack-years, SBP, HDL cholesterol, alcohol and the interaction between age and alcohol. In women, only age and SBP were independently associated with mean IMT (0.58+/-0.09 mm). CONCLUSIONS: We found thinner IMT than those found in high-risk populations, suggesting that an increased IMT might reflect local atherosclerosis. Protective factors such as HDL cholesterol or regular and moderate alcohol consumption are probably important determinants of the early stages of atherosclerosis in these low-risk populations.

Adult↗

Intermittent claudication in older patients. Practical treatment guidelines.

The prevalence of intermittent claudication (IC) increases with age; when questioned, older patients consider increased difficulty in walking to be a normal consequence of aging. Although the prognosis for the involved limb with IC is relatively good, IC is an important clinical predictor of increased cardiovascular mortality. It is important to effect a minimal strategy for determining the presence of lesions in different vascular regions: carotids, coronaries, aorta and renal arteries. The goals for the treatment of IC in the elderly are to improve the walking distance and quality of life and to increase survival. Practical guidelines for the treatment of IC are to first establish a correct diagnosis. Then, patients have to apply life-style modifications and participate in an exercise programme, with the next treatment step involving the use of antiplatelet drugs. However, it must be remembered that older patients could have limitations on exercise; in such cases, a vasoactive drug should be considered. The third guideline consists of multifocal evaluation of the arteries, specifically the coronaries, carotids and abdominal aorta. The existence of an iliac obstruction or stenosis requires consideration of the 2 last guidelines. In more than 75% of cases, elderly patients have femoropopliteal or distal arterial obstructions: exercise and a vasoactive drug should be employed in these instances. The presence of iliac lesions has to be discussed in the presence of a multidisciplinary team in a vascular centre, and should consider the usefulness of percutaneous transluminal angioplasty or surgery.

Aged↗

Comparative of blood flow to the ankle-brachial index after iliac angioplasty.

BACKGROUND: Interest of blood flow and ankle brachial pressure index (ABPI) to evaluate result of iliac angioplasty. METHODS: ABPI and blood flow rates were measured before and after angioplasty in 22 lower extremities of 16 patients with iliac stenosis. Blood flow rates were determined by means of a nuclear magnetic resonance (NMR) flow meter. RESULTS: The day after angioplasty, flow and pressure were increasing significantly, whereas a month later, only blood flow was increasing significantly. In a group of patients with near-normal ABPI before angioplasty (ABPI > or = 0.8), there was, on the day following the angioplasty, a significant increase in ABPI and pulsatile blood flow rates; flow rates increased considerably a month after the operation whereas ABPI stay stable. In a group of patients with clearly abnormal ABPI before angioplasty (ABPI <0.80), there was a significant increase in ABPI and blood flow rates the day after angioplasty and again a month later. CONCLUSIONS: Flow therefore seems to vary independently of pressure. The possible use of flow measurement to detect restenoses is yet to be studied.

Adult↗

Prevalence of venous insufficiency in French adults of the SUVIMAX cohort. SUpplémentation en VItamines et Minéraux AntioXydants.

BACKGROUND: The symptoms of venous insufficiency of the lower limbs (VILL) include a feeling of heaviness in the legs, pain, and nocturnal cramps, which may be combined with organic disorders (varicose veins). The objective of this study was to determine the prevalence of VILL in terms of both varicose veins and functional symptoms in the participants of the SUVIMAX cohort, which is representative of the French population for the age range under consideration (women: 35-60; men: 45-60). METHODS: Information on the venous status of 3065 subjects in the SUVIMAX cohort were collected from three different sources: yearly systematic clinical examination (1994-1996), monthly follow-up by a telematic network (1994-1998) and non-specific questionnaire (1997). Two mutually exclusive populations were thus defined on medically diagnosed varicose veins and venous insufficiency and reported varicose veins and venous insufficiency. RESULTS: Venous insufficiency was medically diagnosed in 192 men (14.6%) and 584 women (33.6%), and varicose veins were diagnosed in 143 men (74.5%) and 317 women (54.2%) from this group. Prevalence reported symptoms of venous insufficiency and of varicose veins was 13.6% and 7.4% respectively in men and 28.2% and 12.4% in women. Sex, age, body mass index and number of pregnancies were found to be correlated with the risk of venous insufficiency. CONCLUSIONS: VILL is a very common disease in French adults both as varicose veins and as functional symptoms. Venotonics were the main type of treatment but not enough use is made of elastic compression stockings.

Adult↗

Higher-order spectral analysis in laser-Doppler flowmetry signal processing.

This paper presents an application of higher order statistics and spectra to the problem of laser-Doppler Flowmetry (LDF) for microcirculation monitoring. The proposed signal processing technique computes the bispectra of LDF signals after appropriate pre-processing and extracts features which can be used for classification of the signals to a normal or patient category. Bispectra are defined in terms of the third-order moments or cumulants of signals and are shown to contain valuable information for the above classification of LDF signals. Experimental studies, including (a) a set of 17 normal subjects and 69 patients with Raynaud's phenomenon and (b) 50 LDF-signals separated to four groups from patients that have different pathologic characteristics, are described and results are presented which illustrate the performance of the proposed approach when applied to the LDF signals.

Adult↗

Time-variant spectral analysis of LDF signals on the basis of multivariate autoregressive modelling.

Time-variant AR-modelling was used to analyse the non-stationary properties of LDF signals during provocation tests. The procedure for the estimation of time-varying AR parameters based on Kalman filtering is presented. The estimates can be used to calculate instantaneous measures, such as peak frequency, spectral band power and coherence. The resulting course of instantaneous peak frequency of a sinusoidal signal with frequency jump was compared to similar parameters derived from short-time FFT and Hilbert transformation. Univariate time-variant spectral analysis was used to investigate LDF measurements in patients with Raynaud's phenomena. The experimental protocol was splitted into phases of different room temperature. The results demonstrate time-dependent variations of spectral components (amplitude and frequency). By means of time-variant coherence analysis of LDF and diameter measurements of vessels in a hamster skin fold the existence of a main rhythm around 0.1 Hz in the LDF signals which is related to vasomotion is shown.

Algorithms↗

Different flowmotion patterns in healthy controls and patients with Raynaud's phenomenon.

Flowmotion was characterized in healthy controls and 61 Raynaud's phenomenon (RP) patients by spectral analysis of laser-Doppler perfusion monitoring (LDPM) tracings. Healthy subjects flowmotion patterns revealed a main frequency of 3 cycles per min (cpm) with another low frequency and heart rate synchronous components. A first group of RP patients presented a low frequency and heart rate frequency component but no significant difference in blood flow. The second group presented the predominating heart rate related frequency with low microvascular perfusion. The third group presented a flowmotion pattern with overlapping of heart rate and low frequency components. Patients with primary and secondary RP show specific changes in flowmotion, probably related to increased sympathetic nervous activity or vessel wall alterations causing disappearance of arteriolar tone and impairment of microvascular perfusion. The group of patients with overlapping frequency components presents an intermediate flowmotion pattern indicating a different grade of alterations in microvasculature.

Adolescent↗

Spectral analysis of laser-Doppler perfusion signal measured during thermal test.

The method of spectral analysis of laser-Doppler perfusion signal measured during thermal test is proposed. During three 20 min phases with 40, 5, and 40 degrees C of thermal test laser-Doppler perfusion signal was recorded. For each signal phase frequency spectra were calculated using the FFT method. Quantitative parameter Spectral Factor for results evaluation was proposed. In total 94 patients were measured: 69 with Raynaud's phenomenon and 25 normal subjects. Additionally in 18 Raynaud's patients the influence of Nifedipine was studied. Results suggest that proposed parameter is able to differentiate between Raynaud's patients and normal subjects and that is useful for evaluation of Nifedipine effectiveness. However, further studies are needed to improve the method to differentiate between primary and secondary Raynaud's patients.

Adult↗

Dynamic characteristics of laser-Doppler flux in normal individuals and patients with Raynaud's phenomenon before and after treatment with nifedipine under different thermal conditions.

The study was aimed at choosing an appropriate characteristic of laser-Doppler flux (LDF) data for (1) distinguishing patients with Raynaud's disease from normal controls and (2) evaluating the effect of nifedipine under different thermal conditions. We checked the reliability of three characteristics of nonlinear dynamics as statistical dimension Ds, correlation dimension D2 and power-law index PLI. Their values depended heavily on the thermal condition. The most reliable characteristics that enabled us to distinguish the patients from normal controls and the effect of nifedipine under definite thermal condition proved to be Ds and PLI. The latter is simple for computation and is thus recommendable for clinical practice. Ds and PLI were higher in patients with Raynaud's compared to normal controls and diminished during the transitions from low to high temperature. However, the characteristics used were unable to distinguish significantly Raynaud's I from Raynaud's II patients.

Algorithms↗

Linear and nonlinear analysis of blood flow in healthy subjects and in subjects with Raynaud's phenomenon.

The paper presents analyses of the dynamics contained in the blood flow signals measured on healthy subjects and on subjects with primary Raynaud's phenomenon. Different signal processing methods are presented and discussed. The dynamics was evaluated in the time and frequency domains and in phase space. Additionally, changes in the basal value during temperature provocation were studied using multiresolution analysis. The analyses demonstrate differences between the blood flow dynamics in healthy subjects and subjects with Raynaud's phenomenon. Moreover, the observed decrease in the amplitude of oscillation in regions approximately 0.04 Hz and approximately 0.1 Hz suggests an impairment in the neurogenic and the myogenic regulation of the blood flow. The administration of nifedipine in subjects with Raynaud's phenomenon results in an increase in the basal value and in the amplitude of the blood flow component oscillating with the heart rate. However, it does not restore the dynamics to that found in healthy subjects.

Adolescent↗

[Treatment of deep venous thrombosis at home: evolution from ideas to medical practice].

The diagnosis of Deep Venous Thrombosis (DVT) by duplex ultrasound is absolutely possible out of specialized centers. Low Molecular Weight Heparins (LMWH) allow to obtain a greater efficacy and safety compared to Unfractionated Heparin (UFH). The control of LMWH is very reduced. Two studies have just been published on the topic of treatment of DVT at home. The group of patients treated at home with LMWH is not presenting more complications than the group of patients initially treated at the hospital with UFH. Nevertheless, these studies concern a very selective population of patients. Our center has been proceeding to a study for 4 years (1993-1997) in comparing the treatment at home of proximal DVT by LMWH then oral anticoagulant, to the initial treatment (10 days) in hospital by also using LMWH then oral anticoagulant. The first results show that there is no difference between both groups in terms of end-points: death, extension or recurrence of the thrombus, pulmonary embolism, bleeding. Therefore, the treatment of some type of proximal DVT is possible at home. Nevertheless, it is necessary to be very cautions as the population studied so far is a selected one. Etiologies of DVT are a constant obsessive fear. DVT or pulmonary embolism represents a real general disease which is going to progress along life. The intervention of a specialized center is always necessary. It is a work in team which must get the upper hand compared to an isolated medical action.

Adolescent↗

Comparative efficacy of a single daily dose of two capsules Cyclo 3 Fort in the morning versus a repeated dose of one capsule morning and noon. A one-month study.

BACKGROUND: The efficacy of Cyclo 3 Fort has previously been demonstrated in placebo-controlled trials on plethysmographic and clinical parameters. Its objective was to demonstrate that after one month of therapy, the efficacy and safety of a single dose of two capsules of Cyclo 3 Fort in the morning were comparable to that of a twice daily dose of Cyclo 3 Fort, one capsule morning and noon. METHODS: This single-center, randomised, double-blind study was conducted on 37 women with chronic lower-limb venous insufficiency, associating clinical or functional signs and abnormal plethysmographic values. Clinical parameters measured were those conventionally used to assess superficial venous insufficiency; the main laboratory parameter evaluated by plethysmography was the index of venous distensibility. RESULTS: The results data show that in each of the study groups, all of the patients attained a significant improvement in their clinical conditions, confirmed by laboratory tests, following one month of therapy with Cyclo 3 Fort. On the other hand, comparison of results data between the two groups did not objectify any significant difference between the two treatment modalities. CONCLUSIONS: Thus a single dose of two capsules of Cyclo 3 Fort in the morning appears as effective and as well-tolerated as a twice daily dose of one capsule of Cyclo 3 Fort morning and noon.

Administration, Oral↗