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H Boccalon

Publications and source records attributed to H Boccalon.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Lines of conduct for training of physicians in echography and vascular Doppler and realization of vascular ultrasonic tests].

Vascular tests with duplex scanning have an important lace in the diagnostic and therapeutic strategy in vascular medicine; they are integrated by the physician within the strategy of pathology support. The realization and interpretation of vascular duplex scanning are subject to recommendations. The training of physicians takes into account the clinical context due to the fact that all aspects of these examinations are inseparable. Besides the theoretical education, it is important to be thorough in practical training. The realization of a minimal number of 250 examinations is advised, distributed among different sectors of anatomy and pathology. The acquiring and preservation of technical skills and the ability to provise solutions, requires the realization of additional 250 examinations. This total amount of 500 examinations is integrated into a global 2 year educational program. The preservation of skills requires 500 annual examinations. The training center is placed under the responsibility of a clinical physician, recognized in vascular medicine. This center must perform more than 2,000 examinations a year. Various centers can associate their abilities in order to ensure a complete training program.

Blood Vessels↗
PubMed1997

Characteristics of chronic venous insufficiency in 895 patients followed in general practice.

BACKGROUND: This study was designed to describe the main semiological and etiological characteristics of chronic venous insufficiency (CVI) and to determine if there was a relationship between the extent of objective signs, severity of symptoms and aetiology. MATERIALS AND METHODS: 895 outpatients presenting CVI of the lower limbs over a period of at least one year, irrespective of grade of severity or aetiology, were included in this retrospective study. They were treated with 2 different pharmaceutical forms of the same venoactive medication (1000 mg of micronised flavonoid fraction) for 2 months. Organic CVI (OCVI) was classified, in stages of increasing severity, according to the Widmer and Porter classification. In the absence of anatomical lesions of the main veins or their valvular system, CVI was termed functional (FCVI). RESULTS: Analysis indicated that CVI was more frequent in women than in men (sex ratio 10:1). 26% were FCVI and 91% of OCVI were of varicose origin. The mean progression time of the disease was 13+/-11 years. Disease began earlier in women than in men (34+/-14 vs 41+/-14 years). Oedema was the first objective sign in 68% of patients and the only one in 20% of FCVI. Heaviness was more frequent in FCVI and its intensity was not related to the severity of CVI. Trophic complications were more frequent in the advanced stages. CONCLUSIONS: In order to avoid progression to more severe forms which are disabling or expensive to treat, a rational approach to the management of early CVI is essential.

Adolescent↗
PubMed1996

[Diagnosis of deep venous thrombosis of the lower limbs].

The diagnosis of deep vein thrombosis (DVT) of lower limbs comprises three stages: clinical evocation, paraclinical confirmation, and etiologic detection. In a context with thrombogenic risk, a clinical sign evokes this diagnosis; nevertheless, it has to be confirmed as complications of DVT and risks of anticoagulation are essential. The realization of a test is compulsary; phlebography is the exam of reference which is not used anymore in routine; venous echo-Doppler is the most useful exam for the practitionner; the dosage of D-dimers excludes thrombosis if it is negative but its practice must be optimized. Clinical situations in which these tests are suggested are: a clinical suspicion of DVT, with a privileged place for echo-Doppler; a context of asymptomatic DVT which is the most difficult problem (only phlebography is validated in that case); the recurrence of thrombotic events where a previous exam of reference renders the detection of a recent trouble easier; pulmonary embolism where echo-doppler is looking for the presence of the source of a peripheral thrombus. The etiologic assessment has three levels: the analysis on the context and the risk factors of venous thrombosis; the realization of an hemostasis assessment and the dosage of physiologic inhibitors of coagulation in some suggestive clinical conditions; the research of an associated malignant disease.

Humans↗
PubMed1996

Predicting daily maintenance dose of fluindione, an oral anticoagulant drug.

Due to large inter-individual variations, the dose of vitamin K antagonist required to target the desired hypocoagulability is hardly predictible for a given patient, and the time needed to reach therapeutic equilibrium may be excessively long. This work reports on a simple method for predicting the daily maintenance dose of fluindione after the third intake. In a first step, 37 patients were delivered 20 mg of fluindione once a day, at 6 p.m. for 3 consecutive days. On the morning of the 4th day an INR was performed. During the following days the dose was adjusted to target an INR between 2 and 3. There was a good correlation (r = 0.83, p < 0.001) between the INR performed on the morning of day 4 and the daily maintenance dose determined later by successive approximations. This allowed us to write a decisional algorithm to predict the effective maintenance dose of fluindione from the INR performed on day 4. The usefulness and the safety of this approach was tested in a second prospective study on 46 patients receiving fluindione according to the same initial scheme. The predicted dose was compared to the effective dose soon after having reached the equilibrium, then 30 and 90 days after. To within 5 mg (one quarter of a tablet), the predicted dose was the effective dose in 98%, 86% and 81% of the patients at the 3 times respectively. The mean time needed to reach the therapeutic equilibrium was reduced from 13 days in the first study to 6 days in the second study. No hemorrhagic complication occurred. Thus the strategy formerly developed to predict the daily maintenance dose of warfarin from the prothrombin time ratio or the thrombotest performed 3 days after starting the treatment may also be applied to fluindione and the INR measurement.

Administration, Oral↗
PubMed1996

D-dimer test and diagnosis of deep vein thrombosis: a comparative study of 7 assays.

The current D-Dimer ELISA methods provide high sensitivity and negative predictive value for the diagnosis of deep vein thrombosis but these methods are not suitable for emergency or for individual determination. We have evaluated the performance of 3 newly available fast D-Dimer assays (Vidas D-Di, BioMérieux; Instant IA D-Di, Stago; Nycocard D-Dimer, Nycomed) in comparison with 3 classic ELISA methods (Stago, Organon, Behring) and a Latex agglutination technique (Stago). One-hundred-and-seventy-one patients suspected of presenting a first episode of deep vein thrombosis were investigated. A deep vein thrombosis was detected in 75 patients (43.8%) by ultrasonic duplex scanning of the lower limbs; in 11 of them the thrombi were distal and very limited in size (< 2 cm). We compared the performance of the tests by calculating their sensitivity, specificity, positive and negative predictive value for different cut-off levels and by calculating the area under ROC curves. The concordance of the different methods was evaluated by calculating the kappa coefficient. The performances of the 3 classic ELISA and of the Vidas D-Di were comparable and kappa coefficients indicated a good concordance between the results provided by these assays. Their sensitivity slightly declined for detection of the very small thrombi. Instant IA D-Di had a non-significantly lower sensitivity and negative predictive value than the 4 previous assays; however its performance was excellent for out-patients. As expected, the Latex assay had too low a sensitivity and negative predictive value to be recommended. In our hands, Nycocard D-Dimer also exhibited low sensitivity and negative predictive value, which were significantly improved when the plasma samples were tested by the manufacturer. Thus significant progress has been made, allowing clinical studies to be planned to compare the safety and cost-effectiveness of D-Dimer strategy to those of the conventional methods for the diagnosis of venous thrombosis.

Adolescent↗
PubMed1995

National study of obliterative arterial disease of the lower limbs involving general practitioners in France: Artemio study.

A national survey was performed in France from May to June, 1993. The aim of this study was to evaluate general practitioners' attitudes and behaviors when diagnosing and managing patients with lower extremity arterial disease (LEAD). One thousand general practitioners, randomly drawn from an exhaustive list, were contacted to participate in a telephone interview concerning the last patient with intermittent claudication seen in their practice. Four hundred seventy-six general practitioners participated. Risk factors noted for these 476 patients with intermittent claudication were in agreement with the literature: 86% were men aged 64 +/- 10 years (mean +/- SD) and 14% were women aged 73 +/- 8 years. Sixty-two percent had a pain-free walking distance of between 100 and 500 meters at diagnosis. Forty-five percent were former smokers and 37% currently smoked; 55% had hypertension, 14% diabetes, and 56% disturbances of lipid metabolism. A majority of them were hypercholesterolemic. The diagnosis of the disease was based primarily on a clinical assessment, confirmed for 33% by Doppler or echo Doppler. The mean duration of diagnosis was 4.4 +/- 4.1 years. Management of the disease was mainly by prescription of vasodilators (91%), antiplatelet agents (59%), and anticoagulants (8%). Use of Doppler or echo Doppler was recommended once a year. Infection was observed in 27% of patients. Thirty-eight percent had had a cardiac incident (angina pectoris or myocardial infarction) and 10% a cerebrovascular accident. They differed significantly from those with LEAD alone for the following parameters: age (68.5 +/- 9.2 vs. 63.2 +/- 10.3 years; p < 0.001); duration of LEAD (5.6 +/- 4.6 vs. 3.6 +/- 3.5 years; p < 0.001); hypertension (65% vs. 50%; p < 0.01); and current smoking (29% vs. 43%; p < 0.01). This survey confirmed the feasibility of telephone interviewing, on a large sample of general practitioners in France. The high level of association with other cardiac incidents was, for these patients, a much higher risk of mortality and morbidity than LEAD alone. It would be interesting to validate the associations observed with a prospective study of comorbidity.

Adult↗
PubMed1995

[Early diagnosis of arteriopathy of the legs using measures adapted to general practitioners: the systolic index and pulse perception].

Atherosclerotic lower-limb arteriopathy is a serious disease. Its prevalence often underestimated when relying only on questioning the patient. A simple early detection method is the systolic index, i.e. the ratio of systolic ankle over brachial pressure. This ratio should normally be greater than 0.9. Lower values indicate detectable arterial obstruction as revealed by reduced peripheral perfusion. Under 0.75 patients are considered as suffering from peripheral vascular disease and require further investigations and specialist opinion. With an index between 0.75 and 0.90 patients are classified as stage I or II of the disease. In a survey by 180 General Practitioners, which were trained by angiologists to measure ankle pressure, more than 1,400 patients, between 40 and 75-years old, with at least one vascular risk factor (hypertension, diabetes, lipids, tobacco) were selected. Tobacco was the most prevalent vascular risk factor, then diabetes (particularly in men). 23.8% of patients recorded values between 0.90 and 0.75 and thus suffering from peripheral vascular disease (certainly age dependent). Clinically absent pulses at the posterior tibial and the dorsalis pedis artery were found is 19 and 27% of patients respectively. Most of the patients received a pharmacological substance allowing to check this index sensitivity. Thus systolic index is a simple low cost method for early detection and care and more general utilisation is proposed.

Adult↗
PubMed1994

Comparison of the bone mineral content of the lower limbs in men with ischaemic atherosclerotic disease.

In a previous study, the authors demonstrated that in 17 men with ischaemic atherosclerotic disease the bone mineral density (BMD) of the femoral neck was lower than in matched control subjects. The patients with arterial disease were thinner and were heavier smokers than the controls. Osteoporosis and arterial disease of the lower limbs were perhaps due to common risk factors: tobacco consumption and a low body build index. In order to demonstrate the direct effect of atherosclerosis on bone mineral content (BMC), the authors studied by dual-energy X-ray absorptiometry the BMC of both legs in 18 men presenting symptomatic arterial disease of the lower limbs quantified by measurement of distal systolic indexes by doppler ultrasonography. The mean BMC of the leg more severely affected by arterial disease was significantly lower than the mean BMC of the leg less affected by arterial disease (512 +/- 76 g versus 495 +/- 80 g: p = 0.003). In 13 of the 18 patients, the BMC was lower in the leg more severely affected by arterial disease; in 4 of 18 the difference between the BMC of the left and right legs was less than 1%, and in a single patient the BMC was higher in the leg more affected by arterial disease. Arterial disease of the lower limbs could lead to bone mineral loss.

Adult↗
PubMed1994

Dermatan sulfate is a more potent inhibitor of clot-bound thrombin than unfractionated and low molecular weight heparins.

Clot-bound thrombin proteolyses fibrinogen and amplifies the coagulation cascade at its close vicinity, thereby ensuring the growth of fibrin-rich thrombus. The present study compares the ability of various glycosaminoglycans (GAGs) to inhibit these 2 properties. Unfractionated heparin (UH), 3 low molecular weight heparins (LMWHs) with increasing antifactor Xa/antifactor IIa ratio, the synthetic pentasaccharide (PS), devoid of antifactor IIa activity, and dermatan sulfate (DS), a catalyst of thrombin inhibition by heparin cofactor II, were selected on the basis of their different properties. Proteolysis of fibrinogen by clot-bound thrombin was evaluated by measuring fibrinopeptide A (FPA) generation after an incubation of standardized washed clots in plasma for 120 min in absence or in presence of increasing concentrations of heparins or of DS. The results were compared to those obtained when free alpha-thrombin (0.4 nM) was added to plasma in the same experimental conditions. On the basis of equivalent antithrombin units, UH and LMWHs gave identical results. To inhibit by 70% fibrinogen proteolysis induced by clot-bound thrombin (IC 70), 5- to 9-fold higher concentrations of UH or of LMWHs were required in comparison with those required to inhibit free thrombin. For DS, only a 1.3 times higher concentration was required. PS (final concentration 1 anti Xa U.ml-1) was devoid of any inhibitory effect. The amplification of the coagulation cascade induced by clot-bound thrombin was evaluated by measuring the shortening of whole blood clotting time (WBCT) resulting from the incubation of washed clots in native blood. In absence of GAG, clot-bound thrombin reduced WBCT from 18 +/- 2 min to 9 +/- 1 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Dermatan Sulfate↗
PubMed1993

Influence of long term oral anticoagulants upon prothrombin fragment 1 + 2, thrombin-antithrombin III complex and D-Dimer levels in patients affected by proximal deep vein thrombosis.

We have investigated the influence of long term oral anticoagulants (OAC) upon the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), of thrombin-antithrombin III complexes (TAT) and of D-Dimer in 20 patients affected by a proximal deep vein thrombosis (DVT) diagnosed by ultrasonic duplex scanning. Patients (63 +/- 17 years, mean +/- SD) were sampled at the beginning of the OAC treatment (day 1), which was started 1 to 6 days after diagnosis confirmation and full heparinization, and then 8, 35 and 92 days after. The results were compared to those obtained in a blood donor population (39 +/- 10 years) and to an age-matched healthy population (63 +/- 19 years). The mean INR determined on days 8, 35 and 92 were almost identical (2.8 +/- 0.7, 2.9 +/- 0.9 and 2.8 +/- 0.6 respectively). In contrast, highly significant variations of the three markers were recorded during the observation period. Eight days after the beginning of OAC, increased levels of TAT complexes were associated with subnormal levels of F1 + 2 suggesting persistence of a hypercoagulable state. On the further sampling times, TAT complexes were in the normal range while F1 + 2 were far below the normal range. Between day 1 and day 92, the levels of D-Dimer continuously decreased reflecting a long-term fibrinolytic process. This study clearly indicates that high INR are not systematically associated with very low F1 + 2 levels, particularly in the acute phase of thrombosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Electric stimulation of the spinal cord in arterial diseases of the legs. A multicenter study of 244 patients].

From January 1985 through January 1990, 244 patients (168 males, 76 females, mean age: 69 +/- 14 years) received epidural spinal cord stimulation for the treatment of advanced, nonreconstructable, peripheral vascular disease of the lower limbs due to atherosclerosis in 180 patients, atherosclerosis and/or diabetes in 49, and thromboangiitis obliterans in 15 patients: previous surgery included 101 bypass-grafts in 70 patients, 51% of which below the knee, and 117 sympathectomies in 113 patients as the last resource in face of distal peripheral vascular disease of the lower limbs. Mean ankle-to brachial systolic pressure ratio was .31 +/- .34 on symptomatic limbs; due to pain and advanced disease, walking capacity was assessed in only 151 patients, either on treadmill in 25, or in a metered corridor in 126; angiogram of the lower limbs was performed in every patient unless one not older than three months was readily available; pain at rest was assessed after an analogical scale; partial transcutaneous oxygen tension was measured on the dorsum of the fore-foot of 77 symptomatic limbs (mean: 13.35 +/- 14 mmHg). According to clinical and functional evaluation, 18 patients had exertional ischemia (group I), 87 had permanent ischemia with pain at rest and no tissue loss (group II), and 139 had chronic tissue loss (group III), including 93 ischemic ulcers (mean surface: 3.7 cm2, mean duration: 3.5 months) in 88 patients, 27 limited gangrene, and 24 previous limited non-healing distal amputation. After temporary spinal cord stimulation at T12-L1 level (mean duration: 9 +/- 4 days) with a percutaneous quadripolar electrode lead had allowed for selection of responders, 212 patients received an implantable neurostimulator.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Development of diagnosis and treatment of arterial diseases over the course of time].

The preoccupations of medicine vary during its history in relation to the socio-economic problems of the day and in relation to the diagnostic and therapeutic possibilities of the day. From a diagnostic standpoint, arterial claudication was described as early as 1830, i.e. almost a century before the standard classification of Leriche and Fontaine. Arterial investigations have been known for a great many years in terms of their principles (1662 for plethysmography, 1843 for Doppler effect). Their medical applications nevertheless date from only the past 20 years. Arterial imaging dates from the start of the century, but followed a very wide range of paths before reaching the technical advances of the present day. The oldest form of treatment is that of limb amputation. There has been extensive clinical and physiological discussion of hyperhemic techniques. In terms of arterial reconstruction, the debate has shifted from open access surgical reconstruction to percutaneous endoarterial reconstruction. However, the history of the diagnosis and treatment of arterial disease, although preoccupied by new and numerous techniques, has also involved the restructuring of patterns and ideas. The current attitude involves global management of all diseased arteries since the underlying problem is common and multifocal.

Angiography, Digital Subtraction↗
PubMed1992

[Lower limb arteriopathy and male osteoporosis].

There are close links between bone metabolism and bone circulation. Osteoblasts are derived from the walls of the venous sinuses. As shown by Burkardt, osteoporosis is accompanied by a decrease in the number of intra-osseous capillaries, and intra-osseous arterioles may be the site of arteriosclerosis lesions. In order to determine the existence of a possible link between arteriosclerosis and male osteoporosis, the etiology of which is often poorly defined, the authors studied phosphorus-calcium balance, X-rays of the spine, and bone density of the spine and the femoral neck in 17 male arterial disease sufferers with a mean age of 61 and at Leriche stage 2, 3 or 4. These 17 patients were compared with 15 age-paired controls. Wedge fractures, absent in the control group, were seen in 9 of the 17 patients. Bone mineral content in the femoral neck was significantly reduced in the arterial disease group.

Arteriosclerosis↗