[College of the French Vascular Medicine Teachers (CEMV) statement: Arterial Doppler waveforms analysis (simplified Saint-Bonnet classification)]

Lower extremity peripheral artery disease is a frequent disease. Arterial Doppler waveforms analysis is a key element in vascular medicine, especially to diagnose lower peripheral artery disease. Although Doppler waveforms are often used, descriptions are highly heterogeneous. This review presents the simplified Saint-Bonnet classification that is tought to vascular medicine residents in order to homogenize arterial flow description.

Volume Calculation of Venous Thrombosis Using 2D Ultrasound Images

Venous thrombosis screening exams use 2D ultrasound images, from which medical experts obtain a rough idea of the thrombosis aspect and infer an approximate volume. Such estimation is essential to follow up the thrombosis evolution. This paper proposes a method to calculate venous thrombosis volume from non-parallel 2D ultrasound images, taking advantage of a priori knowledge about the thrombosis shape. An interactive ellipse fitting contour segmentation extracts the 2D thrombosis contours. Then, a Delaunay triangulation is applied to the set of 2D segmented contours positioned in 3D, and the area that each contour defines, to obtain a global thrombosis 3D surface reconstruction, with a dense triangulation inside the contours. Volume is calculated from the obtained surface and contours triangulation, using a maximum unit normal component approach. Preliminary results obtained on 3 plastic phantoms and 3 in vitro venous thromboses, as well as one in vivo case are presented and discussed. An error rate of volume estimation inferior to 4,5% for the plastic phantoms, and 3,5% for the in vitro venous thromboses was obtained.

Overestimation of moderate carotid stenosis assessed by both Doppler US and contrast enhanced 3D-MR angiography in the CARMEDAS study

PURPOSE

To evaluate the agreement and diagnostic accuracy of Contrast enhanced magnetic resonance angiography (CE-MRA), Doppler ultrasound (DUS) and Digital subtraction angiography (DSA) in the assessment of carotid stenosis.

METHODS

DUS, CE-MRA and DSA were performed in 56 patients included in the Carotide-angiographie par résonance magnétique-échographie-doppler-angioscanner (CARMEDAS) multicenter study with a carotid stenosis ≥ 50%. Three readers evaluated stenoses on CE-MRA and DSA (NASCET criteria). Velocities criteria were used for stenosis estimation on DUS.

RESULTS

CE-MRA had a sensitivity and specificity of 96-98% and 66-83% respectively for carotid stenoses ≥ 50% and a sensitivity and specificity of 94% and 76-84% respectively for carotid stenoses ≥ 70%. The interobserver agreement of CE-MRA was excellent, except for moderate stenoses (50-69%). DUS had a sensitivity and specificity of 88 and 75% respectively for carotid stenoses ≥ 50% and a sensitivity and specificity of 83 and 86% respectively for carotid stenoses ≥ 70%. Combined concordant CE-MRA and DUS had a sensitivity and specificity of 100 and 85-90% respectively for carotid stenoses ≥ 50% and a sensitivity and specificity of 96-100% and 80-87% respectively for carotid stenoses ≥ 70%. The positive predictive value of the association CE-MRA and DUS for carotid stenoses ≥ 70% is calculated between 77 and 82% while the negative predictive value is calculated between 97 and 100%. CE-MRA and DUS have concordant findings in 63-72%, and the overestimations cases were recorded only for carotid stenosis ≤ 69%.

CONCLUSION

Combined DUS-CE-MRA is excellent for evaluation of severe stenosis but remains debatable in moderate stenosis (50-69%) due to the risk of overestimations.

Complete venous ultrasound in outpatients with suspected pulmonary embolism

BACKGROUND

Compression ultrasonography (US) confined to the proximal veins is usually performed to detect deep vein thrombosis (DVT) in patients with suspected pulmonary embolism (PE). Recent studies suggested a limited yield of proximal US when multislice computed tomography (MSCT) was used.

OBJECTIVES

To assess whether performing an additional distal vein US would increase the diagnostic yield of the test.

PATIENTS AND METHODS

Data of 855 consecutive outpatients included in a multicenter randomized controlled trial were analyzed. Patients were investigated by a sequential diagnostic strategy including clinical probability assessment, D-dimer measurement, proximal US and MSCT. Proximal US was completed by an examination of the distal veins, the result of which was not disclosed to the physician in charge of the patient.

RESULTS

US was positive in 21% of patients, of whom 10% (53/541) had proximal DVT and 11% (59/541) isolated distal DVT. Of the 59 patients with distal DVT, 21 (36%) had no PE on MSCT. Twenty of those 21 patients were not given anticoagulant therapy and had an uneventful follow-up. The diagnostic performance of distal US for the diagnosis of PE was as follows: sensitivity 22% [95% confidence interval (CI) 17-29]; specificity 94% (95% CI 91-96); positive likelihood ratio 3.9 (95% CI 2.4-6.4).

CONCLUSIONS

In patients with suspected PE, distal US has limited diagnostic performance, and its additional use only modestly increases the yield of US. Moreover, it carries a high false-positive rate, impeding the use of distal US as a confirmatory test for PE.

Échosclérothérapie à la mousse par ponction-injection directe à l’aiguille : technique et doses

Foam echosclerotherapy by puncture - direct injection (EMPID) is a technique approved by the French Health Authorities for the management of varicose veins. It combines two principles: the injection of a sclerosing agent by echomonitored direct puncture and the use of this sclerosing agent as a foam. The procedure consists of four stages: targeting of the vein to sclerose and selection of the puncture site, venous puncture under echographic guiding, injection of the sclerosing product under complete echographic monitoring, and post-injection control, checking for the impact of the action and the distribution of the foam in the treated vein. First intention indications concern essentially isolated troncular reflux in lesser and great saphena veins and varicose recurrences. In second intention, EMPID is also an alternative to conventional varicose resection surgery. Emphasizing the principle of precaution, we underline the usefulness of a fine, extemporaneous, standardized and reproducible microfoam - high doses, in particular large volumes of foam, are unwarranted since it has been proven that small volumes are as effective. The recommended concentrations are directly linked to the maximal diameter of the saphena trunks targeted. The volume of foam to be injected must be determined on an individual basis and depends on the presence or not of post-injection spasm, the degree of venous filling and the endothelial impregnation of the treated varicosity (which can be easily monitored because of the spontaneous visualization of the foam producing a tracing effect on the ultrasound); it should not exceed 7.5 ml per session. Apart from the classical side effects due to the liquid form, the foam presents its own, very rare, side effects consisting of minor, constantly and spontaneously reversible, eye disorders. The foam is contraindicated for patients suffering from migraine due to higher incidence of such visual disorders. EMPID is an outpatient procedure for the treatment of varicosities which requires considerable operator skill. This technique cannot be proposed on a large scale without proper and specific training.

Prevention of venous thrombosis in patients with acute intracerebral hemorrhage

OBJECTIVE

To assess intermittent pneumatic compression (IPC) in the prevention of venous thromboembolism (VTE).

METHODS

The authors randomly allocated patients with a documented intracerebral hemorrhage (ICH) to elastic stockings (ES) alone or combined with IPC. The primary outcome was a combined criteria assessed at day 10: a symptomatic and well-documented VTE, or a death arising before day 10 and related to pulmonary embolism (PE), or an asymptomatic deep vein thrombosis (DVT) of the lower limbs detected by compression ultrasonography (CUS). Outcome assessment was blinded.

RESULTS

One hundred fifty-one patients were randomized; 133 (88%) patients were evaluated at day 10. No clinical suspicion of VTE arose before day 10. Fourteen patients died before having a CUS but no death was definitely related to PE. Fourteen asymptomatic DVT were detected by CUS: three (4.7%) in the ES + IPC group (all distal) and 11 (15.9%) in the ES group (three proximal and eight distal). ES combined with IPC is associated with a reduced risk of asymptomatic DVT compared to ES alone: relative risk, 0.29 (95% CI 0.08 to 1.00).

CONCLUSIONS

Asymptomatic deep vein thrombosis (DVT) was detected at day 10 in 15.9% of patients wearing elastic stockings alone. Intermittent pneumatic compression significantly decreased the occurrence of asymptomatic DVT for patients with intracerebral hemorrhage.

[Drug addiction and cardiovascular pathologies]

Drug addiction which entails cardiovascular risks unknown or misknown to physicians, currently involves an increasing number of miscellaneous drugs, existing in manifold forms. There appears to be no bounds on the way of intake. All territories of the body may be affected with more or less severity. In young people, the cardiac, coronary, cerebral and peripheral vascular systems are generally involved. Two illicit drugs, cannabis and cocaine, showing a permanent increase in misuse, prevail. This drug addiction comes along with intercurrent pathologies which have their own vascular toxicity, especially HIV infection. Moreover, the advent of new illicit substances emphasizes the complexity of the clinical presentations. These complex situations have a real social and medical impact. We are currently in a phase of permanently increasing risk of cardiovascular complications. The pathophysiological mechanisms involved are intertwined and complicated by the frequent association of polytoxicomania or by the effects excipients added to these drugs: direct vascular toxicity, angeitis, arterial and venous thrombosis. Arsenic, a common component of these drugs, is also found in cigarettes; arsenic toxicity mainly affects the lower limbs. Treatment of these complications is non-specific; the ideal solution being weaning which, unfortunately in this peculiar population of patients, may entail serious complications due to the misuse of substitution products.

Traitement antirétroviral et risque cardio-vasculaire

Current antiretroviral therapy protocols enable long-term survival of HIV-infected patients, decreasing the risk of infectious complications. Three classes of anti-HIV treatments are available. With longer survival, unusual cardiovascular complications related to iatrogenic biological anomalies (dyslipidemia and impaired glucose tolerance) have appeared among this young population which is exposed to usual risk factors of atherosclerosis. Antiretroviral therapies are suspected to cause these complications, inducing maturity-onset diabetes in 4 to 20% of patients, impaired glucose tolerance in 15 to 60%, hypertriglyceridemia in 15 to 74% depending on the survey, and hypercholesterolemia in 20 to 60%, especially in case of associated lipodystrophia. A lipid battery including total cholesterol, HDL, and triglycerides, and 12-h fasting blood glucose should be obtained before initiating antiretroviral therapy. Any anomalous finding should be followed carefully with regular surveillance every 3 to 6 months and search for other causes of secondary dyslipidemia. In the event of casual and persisting elevation of LDL-cholesterol levels, a statin treatment can be introduced. For secondary prevention, irrespective of the context, recommendations currently merge with the consensus applying to the general population. These patients require careful surveillance of cardiovascular risk factors and a specific care in addition to treatment of their immunodeficiency.

[Vascular resistances in lower limb arterial disease used to evaluate the quality of peripheral arteries. Preliminary study]

Peripheral resistance of lower limb arteries is not a common clinical measurement despite easy-to-apply non-invasive techniques. The aim of our trial has been to test this new parameter as a marker of arterial lesions.

MATERIAL AND METHODS

In this prospective study, hemodynamic data acquired non-invasively [Ankle brachial index (ABI), peak systolic velocity (PSV), end-diastole velocity (VTD) and peripheral artery quality] in patients with lower limb arterial disease were compared with the resistance index measured in the common femoral artery (Arbeille index: IR=VTD/PSV).

RESULTS

Between February 1, 2003 and April 30, 2003, 150 measurements of resistance index were made in 99 individuals with ischemia following a strain (69% men, 31% women, average age 64.8+/-15.2 years). Forty-one of the resistance measurements (27%) were also made in patients with arterial disease factors (diabetics, renal replacement therapy). The resistance index was closely associated with end-diastole velocity. (r=-0.76; DDL=148; p<0.01) as well as peripheral artery quality (r=0.81; DDL=148; p<0.01); on the contrary the resistance index was not affected by the arterial disease factors (0.3+/-0.1 vs 0.33+/-0.12; p=NS).

CONCLUSION

These findings suggest that the hemodynamic impact might be evaluated more precisely diabetics and renal replacement therapy patients whose hemodynamic parameters are difficult to assess due to their arterial disease factors. Prospective studies are needed to determine the role of the resistance index in the follow up of these patients, and its contribution in comparison with the measurement of end-diastole velocity.

Efficacy of pentasaccharide on a prethrombosis model based on a calibrated stasis by the increase in up-stream venous pressure

On a previous model using Wessler's principle in the rat, we have demonstrated that a partial ligature of the inferior vena cava leading to a 40% increase in up-stream venous pressure was thrombogenic only in association with the infusion of low dose of thromboplastin (90 microg/kg). In these thrombogenic conditions, the infusion of pentasaccharide (Arixtra, fondaparinux) should lead to a strong inhibition of thrombus formation. Therefore, we performed on five groups of 10 rats: stasis alone (group S) with a 40% increase in up-stream venous pressure; stasis and thromboplastin (group ST90); and stasis, thromboplastin and pentasaccharide (groups SPT50, SPT100 and SPT250) at three different dosages (50, 100 and 250 microg/kg). The efficacy of pentasaccharide was measured according to the variations in up-stream venous pressure, thrombus weight and thrombin-antithrombin complexes levels. Only 250 microl/kg pentasaccharide significantly reduced the thrombus weight in comparison with group ST90 (5 mg versus 23.8 mg, P = 0.01) but it was not sufficient to induce a return to the basic state (5 mg versus 0.2 mg in group S, P = 0.049). Thrombin-antithrombin complex levels measured at the end of the experiment were significantly reduced in comparison with group ST90 (16.7 versus 57.8 mg, P = 0.01) and were not statistically different from group S (16.1 versus 16.6 mg, P = 0.65). In conclusion, in a very borderline model toward thrombogenesis, pentasaccharide was able to reduce thrombus weight and abolished biological hypercoagulability.

[Validation of a French translation of the Edinburgh claudication questionnaire among general practitioners' patients]

OBJECTIVES

Intermittent claudication is one of the clinical symptoms of peripheral arterial disease (PAD). The presence of PAD is a high risk marker of cardiac events and stroke. The PAD screening can be enhanced by the use of questionnaires. The Edinburgh Questionnaire presents in its English version better diagnostic performances compared to the Rose (WHO) Questionnaire. The aim of this study is to precise the performances of the French version of the Edinburgh Questionnaire among a population consulting general practitioners.

METHODS

Four centers instructed 10 general practitioners each to the measurement of ankle pressure with a Doppler stethoscope. The physicians administrated the Questionnaire to 10 consecutive consultants in a same day, and measured the pressure on posterior tibial, dorsalis pedis and humeral arteries. With a second questionnaire they collected data concerning age, weight, height, and the presence of major risk factors. The same protocol was repeated a second day on new patients. The diagnosis of PAD was based on an ankle-arm index lower than 0.85 for at least on limb.

RESULTS

The population studied consisted of 727 subjects (351 females and 376 males). The mean age was at 58.3 +/- 16.1 years (ranging from 18 to 83.3 years). The sensitivity of the Questionnaire is at 47% (95% CI: 32.3-61.7%), the specificity at 98.8% (95% CI: 97.5-99.4%), the positive and negative predictive values are respectively at 73.3% (95% CI: 54.1-87.7%) and 94.8% (95% CI: 94.7-97.6%). Among this population of general practitioners consultants, the prevalence of a low ankle-arm index under 0.85 is at 6.7%.

DISCUSSION

The French version of the Edinburgh Questionnaire maintains the very good specificity of the English version. The lower sensitivity could be explained by the choice of the gold standard, namely the ankle-arm index which includes asymptomatic patients with authentic PAD. The use of this Questionnaire can be recommended for the screening of this disease as well as in epidemiological studies.

Diagnostic accuracy of compression ultrasonography for the detection of asymptomatic deep venous thrombosis in medical patients--the TADEUS project

We assessed the accuracy of venous compression ultrasonography (CUS) for the detection of asymptomatic deep vein thrombosis in 122 consecutive patients, with a mean age of 69 years, who were hospitalised in an internal medicine unit. All included patients had CUS within 48 h of admission. Twelve out of 17 patients with a positive CUS underwent phlebography, as the others withdrew their consent, whereas the remaining 105 patients with a negative serial CUS testing were clinically followed-up at 3 months. We found that CUS had a sensitivity and a specificity of respectively 1 (95% CI, 0.73 to 1) and 1 (95% CI, 0.96 to 1) for the detection of asymptomatic deep vein thrombosis. Kappa-coefficients for intra-observer and inter-observer agreements were respectively 0.88 and 0.56. We concluded that venous compression ultrasonography, performed as described, fulfils requirements of a screening test that could be available for prophylactic clinical trials or epidemiological researches.

[Three-dimensional reconstruction calibrated with ultrasonographic images. Application to the measurement of clot volume in vitro]

OBJECTIVE

We used 3D ultrasonographic reconstruction with manual acquisition to study the volume of venous clots in vitro.

MATERIAL AND METHODS

Native 2D ultrasound slices were acquired free hand for 3D reconstruction. The spatial coordinates of each slice were delivered in real time with an electromagnetic captor. We applied a standard ultrasound protocol to test the calibrated 3D reconstruction quantitatively. The volume of 5 clots of increasing size was quantified in vitro using manual segmentation in a double-blind manner by two independent operators.

RESULTS

The comparison tests and the interoperator regression lines evidenced good agreement between real and measured volumes, confirming the coherence of the reconstruction protocol and the feasibility of this technique in a routine medical setting. Intraoperator variability was 7 to 11% and interoperator variability 16.9%.

CONCLUSION

This calibrated 3D reconstruction is compatible with in vitro measurement of venous clots. This technique could be useful to follow the evolution of the head of proximal deep vein thrombi in vivo. It will be more reliable with semi-automatic or even automatic segmentation becomes available.

[Calf muscle venous thrombosis and pulmonary embolism]

INTRODUCTION

The clinical significance of calf muscle venous thrombosis (CMVT) still remains a matter of debate. Detected by ultrasonography, they are overlooked by venography. This prompted us to evaluate the frequency of such localizations and their association to pulmonary embolism (PE).

METHODS

Retrospective review of our database over a three-year period. All patients with an isolated CMVT were included.

RESULTS

Isolated CMVT were detected in 106 patients (mean age 68.6 years; 65% women), that is 12.5% of all venous thromboses diagnosed in the vascular sonography unit over the study period Sixteen associated PE were detected (15%).

CONCLUSIONS

Association of CMVT and PE is not infrequent. Whether or not such thromboses have the potential to extend into deep veins and/or to migrate into pulmonary circulation requires further studies.

[Evaluation of carotid intima-media thickness in patients with severe aortic stenosis. Thrombosis group study in eastern Brittany]

Coronary angiography is a recommended investigation in the preoperative assessment of aortic valve replacement for aortic stenosis in the absence of a reliable non-invasive diagnostic method. Ultrasonographic quantification of carotid artery intima-media thickness, being correlated to the severity of coronary atherosclerosis, could therefore be useful in the screening of coronary artery disease in severe aortic stenosis. The authors studied a group of 100 patients (69.5 +/- 8.5 years: 64 men) with severe aortic stenosis. A control group of 45 patients with coronary artery disease without valvular disease (69.5 +/- 6 years: 30 men) was used for reference. Significant coronary artery disease was found in 21 of the 100 study cases. The average intima-media thickness was 0.608 +/- 0.090 mm. There was no significant difference in intima-media thickness between the coronary and non-coronary patients of the study group (0.612 +/- 0.094 mm and 0.607 +/- 0.094 mm respectively). It was, however, significantly greater in the control group patients compared with the 21 coronary patients in the study group (0.699 +/- 0.082 mm and 0.612 +/- 0.094 mm; p = 0.0004). Finally, 71.1% of patients in the control group had atheromatous carotid artery plaques compared with 59% in the study group (p = 0.005). The measurement of carotid intima-media thickness does not allow detection of coronary patients in severe aortic stenosis. The finding of a lower intima-media thickness in this population compared with coronary patients without valvular disease suggests that aortic stenosis may have a protective effect on the wall thickness of carotid arteries.

Evaluation of a new, rapid, and quantitative D-Dimer test in patients with suspected pulmonary embolism

Previous studies have suggested the utility of D-Dimer ELISA assays in eliminating a diagnosis of pulmonary embolism (PE). Our objectives were to evaluate the performance of a new, rapid, quantitative, and automated Liatest D-Dimer Assay in patients with suspected PE. Three hundred eighty-six consecutive patients referred to our institution between March 1992 and December 1996 for clinically suspected PE, with recent clinical signs not exceeding 1 wk, were included in this study. Diagnosis of PE was based on clinical evaluation, radionuclide lung imaging, lower limb examination, and, when required, pulmonary angiography. D-Dimer performances, for both Liatest D-Dimer and standard D-Dimer ELISA (Asserachrom DDi), assays, were assessed at the end of the study. Among the 386 patients tested, 146 (37.8%) were classified as PE-positive. Liatest D-Dimer assay had a 100% sensitivity (95% confidence interval, 97 to 100%) and a negative predictive value of 100% (95% confidence interval, 94 to 100%). A normal result, below the cutoff of 500 ng/ml, occurred in 83 of the 386 (21%) patients. There was a strong agreement between Liatest D-Dimer and Asserachrom DDi analyses. These findings suggest that this rapid, quantitative, and automated D-Dimer assay provides a useful diagnostic tool for the clinician with regard to exclusion of PE.

Evaluation of a new rapid D-dimer assay for clinically suspected deep venous thrombosis (Liatest D-dimer)

In previous studies, enzyme-linked immunosorbent assays (ELISA) for plasma D-dimer analysis have demonstrated high sensitivity, suggesting their potential usefulness in excluding deep venous thrombosis (DVT). We evaluated the usefulness of a new D-dimer test (Liatest D-dimer) for suspected DVT in a prospective study of patients admitted to the hospital because of recent (not exceeding 1 week before admission) clinical signs. Contrast venography or compression ultrasonography or both were performed within 24 hours of admission. A new quantitative determination of D-dimer concentration using a suspension of microlatex particles coated with specific antibodies was tested. A standard plasma D-dimer ELISA measurement was also performed. Of 464 patients, 276 had a proven DVT (distal, 74; proximal, 202). For a cutoff level of 400 ng/mL, sensitivity of the Liatest method in the diagnosis of overall DVT was 94.6% (95% confidence interval, 92.0%-97.0%), and the specificity was 35% (95% confidence interval, 28%-42%). The sensitivity and negative predictive value were 98.5% and 95.6%, respectively, in the diagnosis of proximal DVT, but only 83.8% and 84.6%, respectively, in the diagnosis of distal DVT. This new rapid Liatest D-dimer assay seems to be highly sensitive and could replace the ELISA method in excluding patients with proximal DVT. Both methods provide lower sensitivity for distal DVT.

Assessment of activated protein C resistance using a new and rapid venom-based test: STA Staclot APC-R

Activated protein C (APC) resistance is related to a single point mutation in the factor V gene (FV:Q506) and appears to be the most common inherited risk factor for venous thromboembolism. A reliable screening test is therefore useful. We aimed to evaluate a new APC resistance test, on the basis of the procoagulant activity present in one snake venom of a crotalidae family: STA Staclot APC-R. We studied 36 consecutive patients with an acute deep venous thrombosis (DVT) confirmed by compression ultrasonography and carrying the FV:Q506 allele, assessed by DNA analysis, 103 of their family members and 35 consecutive patients with a proven DVT but who did not carry the FV:Q506 allele. Blood samples were collected within 24 h of admission for the DVT cases and on the day of medical registration for the family members. Tests were performed blind. The STA Staclot APC-R test, using a cut-off value of 0.80, had an overall sensitivity of 100% (95% CI, 95-100) and a specificity of 98.8% (95% CI, 92.0-99.6). An acute thrombosis process did not influence the performance of the test. We conclude that this test is easy and rapid to perform in every day practice and fulfills the criteria for a screening test.

Early versus delayed introduction of oral vitamin K antagonists in combination with low-molecular-weight heparin in the treatment of deep vein thrombosis. a randomized clinical trial. The ANTENOX Study Group

OBJECTIVE

To compare oral anticoagulant treatment (fluindione) started on either the 1st or the 10th day of a low-molecular-weight heparin (enoxaparin) treatment for deep vein thrombosis confirmed by venography.

DESIGN

An open, multicenter, randomized study in two parallel treatment groups.

INTERVENTIONS

All patients received enoxaparin, 1 mg/kg s.c. twice daily, and oral fluindione, 20 mg once daily, either beginning on day 1 or on day 10 of the enoxaparin treatment. Enoxaparin was discontinued once the international normalized ratio under fluindione was stable between 2.0 and 3.0 over 2 days. Fluindione treatment was maintained during a 3-month follow-up period.

OUTCOME MEASUREMENTS

Specific examinations (venography and/or V/Q lung scanning and/or angiography) were performed only in the event of a clinically suspected recurrence of venous thromboembolism during the 3-month follow-up period. All cases were blindly assessed by an independent Reading Committee.

RESULTS

A clinically suspected venous thromboembolism was confirmed by objective tests in 1 of 223 patients (group of delayed introduction of fluindione; n = 111). Equivalence was demonstrated between the two treatment schedules (p < 0.0001) for a maximal difference of 10% (90% confidence interval: -2.42 to 0.58). The mean duration of hospitalization was significantly reduced (p = 0.0001) in the group with early introduction of fluindione. The incidence of hemorrhage was comparable between the two treatment groups.

CONCLUSION

Early and delayed introduction of oral anticoagulant treatment in association with subcutaneous enoxaparin in patients with deep vein thrombosis was shown to be equivalent in preventing the recurrence of venous thromboembolism. In patients with early introduction of oral anticoagulant, hospitalization was significantly reduced.

The value of a risk factor analysis in clinically suspected deep venous thrombosis

BACKGROUND

The value of a risk factor analysis in the presence of a clinically suspected deep venous thrombosis (DVT) has been assessed mainly in inpatient populations. The aim of this prospective study was to evaluate the potential association between DVT and acquired circumstances suspected as risk factors, in a cohort of outpatients with a clinically suspected DVT.

METHODS

Consecutive outpatients referred for a clinically suspected DVT, with recent clinical signs, not exceeding 1 week, were included. Before venography, all patients were interviewed by a trained physician to detect the presence of risk factors.

RESULTS

From March 1992 to February 1994, 277 patients were included; venography was positive in 162 (58.4%). Five independent variables were significantly associated with the occurrence of DVT; in a multivariate analysis, 64.7% of patients were correctly classified; odds ratios for having DVT in the presence of these underlying conditions were respectively: 1.75 for age over 65 years, 1.68 for prior history of venous thromboembolism, 1.69 for high risk circumstances (any type of surgery or leg trauma within the past 3 months), 5.59 for malignancy, and 2.56 for varicose veins.

CONCLUSIONS

In outpatients referred for a clinically suspected DVT, recognition of associated conditions might increase the certainty of the diagnosis.

[Pulmonary embolism and unusual deep venous thrombosis. Report of two cases]

Contrast venography is the gold standard for the diagnosis of deep vein thrombosis in the lower limb extremities, but it fails to visualize deep veins like deep femoral vein and internal iliac vein. The internal iliac can be examined with duplex scanning if the technique and the examination conditions are correct. As reported in these two cases, thrombosis of these deep veins may lead to pulmonary embolism. The first case is a young female with venous thromboembolic disease in whom internal iliac vein thrombosis was documented only at the second examination. In the second case, deep femoral vein thrombosis appeared early in a comatose young male. This thrombosis may be classified as proximal muscular vein thrombosis. These two cases emphasize the importance of a duplex scanning examination performed with rigorous technique, whose the main limitation being examination conditions.

Diagnostic value of a new sensitive membrane based technique for instantaneous D-dimer evaluation in patients with clinically suspected deep venous thrombosis

BACKGROUND

Plasma D-Dimer analysis, using ELISA assays, has demonstrated in previous studies a high sensitivity, suggesting its utility in excluding deep venous thrombosis (DVT).

AIM

To assess the performance of a new rapid plasma D-Dimer ELISA measurement in suspected DVT patients with recent clinical signs, not exceeding one week.

METHODS

A prospective study of patients admitted for a suspected recent DVT. Contrast venography or compression ultrasonography were performed within 24 h of admission. A new membrane based ELISA technique, which uses an immunofiltration and two complementary monoclonal antibodies was tested. Results were expressed as positive or negative. A standard plasma D-Dimer ELISA measurement was also performed. D-Dimer performances were assessed at the end of the study.

RESULTS

265/448 patients had a proven DVT (72 distal, 193 proximal). The sensitivity of the instantaneous method in the diagnosis of overall DVT is 92 +/- 3.4% (95% CI), and specificity is 36.6 +/- 6.9%. Positive predictive value is 67.7 +/- 4.8% and negative predictive value is 76.1 +/- 8.9%. Sensitivity and negative predictive values reach 97.9 and 94.3% in the diagnosis of proximal DVT, but only 76.3 and 79.7% in the diagnosis of distal DVT. Similar results are observed with the standard ELISA method.

CONCLUSION

This new rapid plasma D-Dimer measurement appears highly sensitive, and could substitute the older ELISA methods. Both methods provide lower sensitivity in the case of a distal DVT location.

[Genetic polymorphism of acetylation and hydroxylation in the Briton population]

Genetic-controlled drug oxidation and acetylation were studied using dextromethorphan and caffeine as test compounds respectively in white Briton subjects (41 Britons and 27 Bigoudens considered as an ethnic group). Phenotyping was performed using the metabolic ratio (MR) calculated as the urinary output dextromethorphan/dextrorphan ratio and the urinary output of 5-acetylamino-6-formylamino-3-methyluracil (AFMU)/1-methylxanthine (1-MX) ratio in subjects given 40 mg of dextromethorphan and 150 mg caffeine respectively. Frequence distribution of hydroxylator and acetylator status in Briton and Bigouden groups showed no significant difference relatively to the French population. However the frequence distribution of the intermediate acetylator group in the Bigouden population was significantly different from that observed in the Briton population (7.4% vs 31.7%). The signification of this latter result was discussed on the basis of genetic transmission.