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H Boccalon

Publications and source records attributed to H Boccalon.

At least 19 recordsLinked to original sources
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↗
PubMed1992

[Vascular exploration tests. Importance for the indications and monitoring of epidural medullary neuro-stimulation].

The clinical diagnosis must be enriched by quantifiable parameters when a new therapeutic method must be tested. We analyse the role of vascular explorations for epidural stimulation and limb arteriopathies. Four different fields of investigations can be defined. Accuracy of the diagnosis: The tests are useful to rule out some differential diagnoses of arterial involvement, and to establish the functional severity (stage III). 1--Treadmill test: nonischemic pain is ruled out: the evolution can be followed up. 2--Doppler velocimetry demonstrates the extent of the dominant arterial involvement in cases of associated lesions. 3--Arterial pressure gradients: their presence demonstrates significant lesions and allows detecting the affected levels. Quantification of severity: After detecting the lesions, their impact must be appreciated. From a macrocirculatory point of view, the measurement of pressures and flow rates is more sensitive than the Doppler study. From a microcirculatory point of view, the tcpO2 is very useful. 1--Arterial pressure: measured in the ankle and the first toe. There are three degrees: non-threatening ischemia (pulsatile Doppler, distal pressure exceeding 30 mm Hg), threatening ischemia (non pulsatile Doppler, distal pressure exceeding 30 mm Hg), irreversible ischemia (no more pulse, no more capillary flow). If there are arterial calcifications, the pressure in the toe must be measured. 2--Arterial flow rate: the average flow rate may be preserved in an arteriopathy, while the pulsatile rate is already degraded. Non invasive electromagnetic or nuclear magnetic resonance flowmeters measure the total muscular flow. Laser Doppler shows the cutaneous flow rate. 3--The tcpO2: normally greater than 60 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)

Electric Stimulation↗
PubMed1991

D-Dimers, thrombin antithrombin III complexes and prothrombin fragments 1+2: diagnostic value in clinically suspected deep vein thrombosis.

This study was performed to determine the accuracy of D-Dimer fibrin derivatives, thrombin-antithrombin III (TAT) complexes and prothrombin fragments 1 + 2 (F 1 + 2) determinations for the diagnosis of deep vein thrombosis (DVT). One hundred and sixteen consecutive patients referred to the angiology unit of our hospital for a clinically suspected DVT were investigated. They were submitted to mercury strain gauge plethysmography and to ultrasonic duplex scanning examination; in cases of inconclusive results or of proximal DVT (n = 35), an ascending phlebography was performed. After these investigations were completed, the diagnosis of DVT was confirmed in 34 and excluded in 82. One half of the patients were already under anticoagulant therapy at the time of investigation. The 3 biological markers were assayed using commercially available ELISA techniques and the D-Dimer was also assayed with a fast latex method. The normal distribution of these markers was established in 40 healthy blood donors. The most accurate assay for the diagnosis of DVT was the D-Dimer ELISA which had both a high sensitivity (94%) and a high negative predictive value (95%). The D-Dimer latex, TAT complexes and F 1 + 2 were far less sensitive and provided negative predictive values which ranged between 78 and 85%. In spite of positive and significant correlations between the levels of the 3 markers, their association did not improve their overall accuracy for detecting DVT. Therefore, with the exception of the D-Dimer ELISA, these markers were of little value for the diagnosis of DVT in this specific population.

Antithrombin III↗
PubMed1991

Prothrombin fragment 1 + 2, thrombin-antithrombin III complexes and D-dimers in acute deep vein thrombosis: effects of heparin treatment.

Plasma levels of prothrombin fragment 1 + 2 (F 1 + 2), of thrombin-antithrombin III complexes (TAT) and of D-dimers were evaluated at several time intervals in 15 patients affected by acute proximal deep vein thrombosis, complicated or not by pulmonary embolism, and treated by conventional heparin therapy for 9 d. The mean levels of the three markers remained significantly increased throughout the period of observation, except for F 1 + 2 on day 9, when compared to normal values established in a population of normal healthy blood donors. However, whereas heparin significantly decreased the plasma levels of F 1 + 2 and of TAT complexes in less than 3 d. D-dimer levels were not significantly altered. Significant correlations were observed between the plasma levels of the three markers but they were not correlated to the actual intensity of heparin treatment evaluated as the activated partial thromboplastin time prolongation. These results indicate that heparin improves the hypercoagulable state associated with a deep vein thrombosis within the first days of treatment as indicated by TAT and F 1 + 2. They also account for the performances of D-dimer assay for the diagnosis of deep vein thrombosis in patients already receiving heparin, a common situation in routine hospital practice.

Acute Disease↗
PubMed1991

[Diagnostic strategy of vascular diseases of the lower limbs].

Peripheral arterial disease requires different diagnostic strategies according to the clinical presentation: tissue ischemia, asymptomatic disease or polyarterial disease. In the presence of resting or effort ischemia, complementary investigations are indicated: arteriography should be reserved for indications of arterial reconstruction: ankle systolic pressure may be measured by all physicians to quantify the distal repercussions of the lesions. Asymptomatic peripheral disease is becoming more widely recognised and may be detected with flowmeter tests. Polyarterial disease is associated with increased mortality of patients with peripheral arterial disease. Symptoms of coronary artery disease are an indication for coronary angiography and myocardial scintigraphy. Patients with cerebrovascular events will require ultrasonic, CT scanning and cardiac investigations. The diversity of the diagnostic approach to peripheral arterial disease is creating a need for a new profile of vascular physicians.

Blood Flow Velocity↗
PubMed1991

Cost effectiveness of non-invasive tests including duplex scanning for diagnosis of deep venous thrombosis. A prospective study carried out on 511 patients.

Recent studies have elucidated the cost-effectiveness of various diagnostic methods used to detect deep venous thrombosis (DVT) of the lower limbs. These methods include Doppler, plethysmography and labelled fibrogen tests. However, duplex scanning has recently proven to be a more reliable examination. With a view to establishing a realistic appraisal of matters as they stand, the authors have carried out a prospective study to compare the relative cost-effectiveness of purely physical examination, duplex scanning associated with strain-gauge plethysmography, contrast venography indicated for each proximal DVT, and contrast venography as a first-choice examination. 511 consecutive patients suspected of DVT of the lower limbs were examined using the various non-invasive methods cited above. 185 of the patients underwent contrast venography. When compared with those of the non-invasive tests, the results of the latter examination provided for extrapolation to the total population of 511 patients so as to better evaluate costs. We are able to conclude that physical examination alone is neither cost-effective nor risk free. Non-invasive tests, which are more reliable, provide annual savings greater than 1,500,000 FF ($ 240,000) with respect to venography. Performing venography for each proximal DVT increases spending by little: savings are again greater than 1,200,000 FF ($ 192,000).

Adolescent↗
PubMed1991

[Venous echography. What value should be attributes to a negative result?].

471 consecutive patients, suspected clinically of a deep venous thrombosis of the lower limbs, underwent two-level ultrasonography. The reliability of the method was assessed by phlebographic comparison in 185 of them (whenever ultrasonography was positive and in one case out of five when negative). Results were striking: 94 per cent sensitivity (100% by approximation) and 86 per cent specificity. The 286 patients who did not undergo phlebography and in whom ultrasonography was negative were followed up for a period of 1 to 12 months (mean: 7.2 months). 119 were not given anticoagulants and 167 were treated with Calciparine (subcutaneous calcium heparin) at the preventive dose 0.20 ml b.i.d. for 7 days. Only two cases of phlebitis were detected: one 9 days after the investigation and the other 8 months later, following exposure to a new thrombogenic risk. There were no fatal pulmonary emboli. No difference was found between the two groups. In total, two-level ultrasonography was shown to be reliable in comparison with phlebography but, above all, when the result was negative the absence of treatment had no untoward effect on the patient.

Adolescent↗
PubMed1990

Treatment of stage II chronic arterial disease of the lower limbs with the serotonergic antagonist naftidrofuryl: results after 6 months of a controlled, multicenter study.

A study was carried out in patients with intermittent claudication (Fontaine's stage II). The atheromatous origin of the disease was confirmed and localized by angiography or Doppler. One hundred eight-three patients were selected initially (day -30) with a pain-free walking distance on a treadmill (at a speed of 3 km/h and a slope of 10%) ranging from 150 to 300 m. During the first month (washout period) all patients received two placebo tablets daily. At the end of this run-in period (day -30; day 0) and after checking walking distance stability (allowed variation: 20% between the two measurements), patients were included in the study. According to this criterion, 112 patients were selected and 94 remained during the whole study. The study was designed in double-blind, using two parallel, randomly selected groups. Fifty-two patients received naftidrofuryl (2 x 316.5 mg tablets daily with meals) for 6 months; 42 patients received placebo under the same conditions. During this period, clinical and paraclinical examinations were carried out every quarter (day 90 and day 180). After checking the initial homogeneity of the naftidrofuryl and placebo groups, the comparison between the two groups indicates a significant improvement in the naftidrofuryl group after 3 months and 6 months of treatment, for the pain-free walking distance. For the maximal walking distance, a significant improvement was found at day 180. Nonparametric analysis (chi 2 test) also indicated a significant improvement for the naftidrofuryl group. These results confirm that naftidrofuryl is beneficial in the treatment of patients with chronic arterial disease.

Adult↗
PubMed1990

[Study of vasomotility in man using plethysmography and flowmetry].

The interpretation of cardiac hemodynamics is indissociable from the study of the peripheral vascular circulation. The latter may now be assessed by non-invasive techniques. Measuring the systemic blood pressure is useful but, in itself, insufficient. The venous sector is usually studied by plethysmographic methods. The commonest of those is occlusion plethysmography either with a mercury gauge or by impedence plethysmography. It is possible to measure venous distensibility, the venous tone. Postural plethysmography improves the study protocol by eliminating the artefact of venous occlusion while respecting the spatial cardiovascular adaptation. The study of the permeability of the capillary walls is a useful complement to venous investigations. Arterial function is approached routinely by qualitative plethysmography which provides little useful information; on the other hand, the measurement of mean arterial blood flow gives a quantitative and physiologically useful parameter. Even better than the mean arterial flow is the pulsatile arterial blood flow which may be measured by pulsed wave Doppler echo, non-invasive electromagnetic flowmetry and NMR flowmetry. Cutaneous blood flow is measured by laser Doppler. It is now possible to measure global pulsatile arterial flow of a segment of limb including its principal and collateral arteries, or the blood flow of a selected artery or even cutaneous blood flow alone. Future trends lie in improving the accuracy of all these measurements of flow and in increasing the possibilities of controlling tissue metabolism. In addition, studies in the microcirculation will become increasingly important: capillary flow, intracapillary distribution, transcapillary exchanges.

Capillary Permeability↗
PubMed1990

[Measurement of arterial flow in the limbs: plethysmography, isotopes, electromagnetic methods].

Measurement of arterial flow is a very old practice, and intra-arterial recordings of pressure and flow have long served as a reference for experimental studies (fig. 1). The definition of a hemodynamic state is inconceivable unless these two parameters are associated. The electromagnetic method using an intra-arterial sensor measures pulsatile flow. Now, technological advances have led to the appearance of other methods providing measurement of mean (plethysmography) and nonpulsatile flow. As a result, there has been considerable confusion between mean arterial and pulsatile arterial flow (Fig. 2). Various studies have emphasized the physiological importance of pulsatile arterial flow and thus the interest in measuring it. The recording of mean flow has often proved disappointing because values are comparable in groups of normal subjects and those with arterial disease. Mean arterial flow can be measured by isotopic methods and plethysmography. Xenon-133 clearance is the isotopic method most often used. Since determination of microcirculatory flow at rest proved of no use, it was necessary to add a hyperemia test reactive to ischemia to differentiate patients with artery disease from normal subjects. Methods involving technetium and thallium have been little used since they require the presence of a nuclear medicine center and are not easily reproducible. There are numerous plethysmographic methods, but only those are studied here which allow measurement of arterial flow. Plethysmography by venous occlusion measures arterial flow by recording the increase in limb volume. The sensor is a mercury strain gauge.(ABSTRACT TRUNCATED AT 250 WORDS)

Arteries↗
PubMed1989

[Application of auto-expansible endoprostheses to arteries of the legs].

An endovascular support inserted percutaneously, may represent an attractive solution to prevent early obstructions and recurrent stenoses after angioplasty (ATP). 23 iliac lesions and 40 femoro-popliteal lesions, symptomatic in 55 patients, were treated with endoprostheses of the Wallstent type. For the iliac implantations, it concerned in one case a recurrence after endarterectomy, 13 cases of recurrent stenoses after ATP and 9 cases of immediate failure of the angioplasty. The mean length of the lesions under treatment was 8 cm (extreme values between 4 and 14 cm). For the femoro-opoliteal arteries, the implants concerned lesions ranging between 3 and 7 cm, in 75 p. cent of the cases, and lesions exceeding 7 cm in 25 p. cent of the cases. Three iliac thromboses and six femoro-popliteal thromboses were reported at the beginning of this study; on the contrary, no thrombosis is present in the last 18 patients treated with oral anticoagulants. The rate of recurrent stenosis is low (none at the iliac level and 10 p. cent at the femoro-popliteal level); in all other cases an excellent clinical result was obtained with a mean follow-up of 18 months.

Adult↗
PubMed1989

[The necessary advantage of measuring the pulsatile arterial flow of the limbs in patients with arterial disease].

Proper determination of vascular haemodynamics requires measurement of flow and pressure. The objective of this study is to provide methods of measurement of the arterial flow, which may currently be performed via an external approach. The techniques in question include non-invasive electromagnetic flowmetry (NMF) and flowmetry by NMR. NMF uses external magnets, the signal is collected by common cutaneous electrodes; the equipment is simple and may be used in a cardio-angeiology office. It main advantage lies in the screening of arterial diseases (very reproductable and sensitive), monitoring of the treatment (unrelated to the operator), study of hardened arteries (diabetes). Flowmetry by NMR requires a more sophisticated and costly equipment; it permits staged measurements, as well as a scan permitting measurements in one single artery; it is mostly used in specialized centres. Arterial lesions may be defined as not yet significant when only the blood pressure is considered, while the pulsatile flow is already altered; transluminal angioplasties performed in these circumstances, permit to restore the clinical picture as well as increasing twofold the initial flow.

Arterial Occlusive Diseases↗
PubMed1989

[Education of patients with arterial disease. A plan for the use of Expert System in angiology via Minitel].

We are presenting a computer program requiring the use of an Expert System accessible by Minitel, intended for patients with arterial disease and their attending physician. The objective is not to make a diagnosis, but to train the patients in applying health measures to the handling and prevention of his/her disease. While remaining anonymous, the patient may consult the program at home, without any time constraint. Only the patient's physician can authorize him/her to have access to the program. The Expert System may adjust the answers to the patients according to the past history and recent data. Contrary to a computer program, new knowledge does not impair the functioning of the system. The physician has access to simplified modules regarding his patient, and specific modules regarding the treatment. Such a system would help general practitioners in following his patient and would facilitate the Doctor-Patient relationship during consultations.

Arterial Occlusive Diseases↗