Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of DVT

  • asymptomatic dvt
  • distal dvt
  • suspected dvt

  • Selected Abstracts

    Comprehensive validation of competencies for dental vocational training and general professional training

    L. Prescott
    This paper outlines a study designed to validate competencies for dental vocational training (DVT) and general professional training (GPT) in order to ensure their accuracy and acceptability. A highly inclusive approach is described whereby all trainers in Scotland were invited to participate in the exercise. The 168 individuals recruited were drawn from all branches of the dental services and all regions in Scotland. Using online or paper questionnaires, quantitative and qualitative data were collected for each competency statement over 9 months, after which focus groups discussed and decided which changes should be made. A high response rate was observed and from the 160 competencies originally identified, almost half (47.5%) were redrafted as a direct result of the validation process. Sections of the competency document that required most attention are discussed, as are the nature of changes made to the competencies. As a result of this study, a fully validated competency document for DVT and GPT has been produced and will allow a high degree of standardization of training through the provision of essential consistent information to trainers and VDPs. [source]

    Incidence of Deep Venous Thrombosis Associated with Femoral Venous Catheterization

    Nabeela Z. Mian MD
    ABSTRACT Objective: To determine in adult medical patients the incidence of deep venous thrombosis (DVT) resulting from femora] venous catheterization (FVC). Methods: A prospective, observational study was performed at a 420-bed community teaching hospital. Hep-arin-coated 7-Fr 20-cm femoral venous catheters were inserted unilaterally into a femoral vein. Each contra-lateral leg served as a control site. Age, gender, number of FVC days. DVT risk factors, administration of DVT prophylaxis, and DVT formation and site were tabulated for each patient. Venous duplex sonography was performed bilaterally on each patient within 7 days of femoral venous catheter removal. Results: Catheters were placed in 29 men and 13 women. Femoral DVT was identified by venous duplex sonography in 11 (26.2%) of the FVC legs and none (0%) in the control legs. Posterior tibial and popliteal DVT was identified in both the FVC and control legs of 1 patient. DVT formation at the site of FVC insertion was highly significant (p = 0.005). There were no statistically significant associations with age (p = 0.42), gender (p = 0.73), number of DVT risk factors (p = 0.17), number of FVC days (p = 0.89), or DVT prophylaxis (p , 099). Conclusion: Placement of femoral catheters for central venous access is associated with a significant incidence of femoral DVT as detected by venous duplex sonography criteria at the site of femoral venous catheter placement. Physicians must be aware of this risk when choosing this vascular access route for adult medical patients. Further studies to assess the relative risk for DVT and its clinical sequelae when using the femoral vs other central venous catheter routes are indicated. Key words: deep venous thrombosis; femoral vein; catheterization; pulmonary embolism. [source]

    Should we give thromboprophylaxis to patients with liver cirrhosis and coagulopathy?

    HPB, Issue 6 2009
    Marco Senzolo
    Abstract Patients with liver cirrhosis are characterized by decreased synthesis of both pro- and anticoagulant factors, and recently there has been evidence of normal generation of thrombin resulting in a near normal haemostatic balance. Although it is generally recognized that bleeding is the most common clinical manifestation as a result of decreased platelet function and number, diminished clotting factors and excessive fibrinolysis, hypercoagulability may play an under recognized but important role in many aspects of chronic liver disease. In fact, they can encounter thrombotic complications such as portal vein thrombosis, occlusion of small intrahepatic vein branches and deep vein thrombosis (DVT). In particular, patients with cirrhosis appear to have a higher incidence of unprovoked DVT and pulmonary embolism (PE) compared with the general population. In dedicated studies, the incidence of DVT/PE ranges from 0.5% to 1.9%, similar to patients without comorbidities, but lower than patients with other chronic diseases (i.e, renal or heart disease). Surprisingly, standard coagulation laboratory parameters are not associated with a risk of developing DVT/PE; however, with multivariate analysis, serum albumin level was independently associated with the occurrence of thrombosis. Moreover, patients with chronic liver disease share the same risk factors as the general population for DVT/PE, and specifically, liver resection can unbalance the haemostatic equilibrium towards a hypercoagulable state. Current guidelines on antithrombotic prophylaxis do not specifically comment on the cirrhotic population as a result of the perceived risk of bleeding complications but the cirrhotic patient should not be considered as an auto-anticoagulated patient. Therefore, thromboprophylaxis should be recommended in patients with liver cirrhosis at least when exposed to high-risk conditions for thrombotic complications. Low molecular weight heparins (LWMHs) seem to be relatively safe in this group of patients; however, when important risk factors for bleeding are present, graduated compression stockings or intermittent pneumatic compression should be considered. [source]

    Thrombotic complications following liver resection for colorectal metastases are preventable

    HPB, Issue 5 2008
    G. Morris-Stiff
    Background. Surgery for colorectal liver metastases (CRLM) can be expected to be associated with a significant rate of thromboembolic complications due to the performance of long-duration oncologic resections in patients aged 60 years. Aims. To determine the prevalence of clinically significant thrombotic complications, including deep venous thrombosis (DVT) and pulmonary embolus (PE), in a contemporary series of patients undergoing resection of CRLM with standard prophylaxis. Material and methods. A prospectively maintained database identified patients undergoing resection of CRLM from January 2000 to March 2007 and highlighted those developing thromboembolic complications. In addition, the radiology department database was reviewed to ensure that clinically suspicious thromboses had been confirmed radiologically by ultrasound in the case of DVT or computed tomography for PEs. Results. During the period of the study, 523 patients (336 M and 187 F) with a mean age of 65 years underwent resection. A major hepatectomy was performed in 59.9%. One or more complications were seen in 45.1% (n=236) of patients. Thrombotic complications were seen in 11 (2.1%) patients: DVT alone (n=4) and PE (n=7). Eight of 11 thrombotic complications occurred in patients undergoing major hepatectomy, 4 of which were trisectionectomies. Patients were anti-coagulated and there were no mortalities. Conclusions. The symptomatic thromboembolic complication rate was lower in this cohort than may be expected in patients undergoing non-hepatic abdominal surgery. It is uncertain whether this is due entirely to effective prophylaxis or to a combination of treatment and a natural anti-coagulant state following hepatic resection. [source]

    The prevention of deep venous thrombosis in physically restrained patients with schizophrenia

    M. De Hert
    Summary Background:, Physical restraint and seclusion are associated with several risks. Antipsychotic drug use increases this risk. Objective:, To evaluate whether the risk of thromboembolism in physical restraint and seclusion of patients with psychosis, treated with antipsychotic medication, was considered by taking preventive measures. Method:, Anonymous data on all consecutively admitted patients with schizophrenia, treated with antipsychotic medication, between 2002 and 2009, were analysed. Diagnostic information and data about seclusion procedures and medication were collected. Preventive measures of thromboembolism in patients in physical restraint were assessed by reviewing case notes and the medication prescribed at the time of seclusion. Results:, Seclusion of patients with psychosis is common. Out of 679 identified patients, 170 had been secluded (472 events). Physical restraint use was not a rare event (N seclusions with restraint use 296, 62.7%). Pharmacological preventive measures (use of heparine dugs) were taken frequently to prevent deep vein thrombosis (DVT) by physical restraint or isolation. Sixty-five (38.2%) out of 170 secluded patients, including a majority of patients who had been under physical restraint, had been administered anticoagulants at the time of seclusion. No cases of DVT occurred. Conclusions:, Preventive measures were routinely administered in clinical practice and were effective in the prevention of DVT. For a clinical setting, it is important to establish a clear and detailed management plan on seclusion and fixation taken into account in all possible risks of physical restraint. [source]

    Current perspectives on the treatment of venous thromboembolism: need for effective, safe and convenient new antithrombotic drugs

    D.F. O'Shaughnessy
    Summary Treatment of venous thromboembolism (VTE) has evolved significantly over the last decade. Low-molecular-weight heparins have largely replaced unfractionated heparin in the treatment of deep-vein thrombosis (DVT) but the majority of patients with pulmonary embolism (PE) continue to be treated with unfractionated heparin. Fondaparinux is the first synthetic selective inhibitor of factor Xa. It has recently been proved to be more effective than, and as safe as, a low-molecular-weight heparin for the prevention of VTE after major orthopaedic surgery. The two large randomised MATISSE trials demonstrated that fondaparinux was at least as effective and as safe as previous reference heparin therapies in the treatment of VTE. Fondaparinux should further simplify the treatment of this frequent disease since a single once-daily fixed dosage regimen may effectively and safely treat both DVT and PE, an important point especially considering the frequent though clinically silent concomitance of these two thrombotic events. [source]

    ORIGINAL ARTICLE: Comparison of a point of care device against current laboratory methodology using citrated and EDTA samples for the determination of D-dimers in the exclusion of proximal deep vein thrombosis

    P. M. BAKER
    Summary D-dimer estimation is a routine part of diagnostic algorithms for the exclusion of venous thromboembolism (VTE). We evaluated a point of care device, Biosite Triage (Inverness Medical UK, Cheshire, UK) for the estimation of D-dimers in both samples taken into citrate and EDTA against our routine laboratory D-dimer (Liatest D-dimer, Diagnostica Stago, Reading, UK) performed on the STA-R Evolution. With informed consent, 102 consecutive patients presenting with possible deep vein thrombosis (DVT) were enrolled and D-dimers along with Wells scores and compression ultrasonography (CUS) were recorded. Using the manufacturers' recommended cut offs of 500 ,g/l fibrinogen equivalent units and 400 ,g/l for the Stago and Triage, respectively, sensitivity, specificity, positive and negative predictive values were calculated. These were 1.00, 0.42, 0.17, and 1.00 for the Triage machine using citrate samples, 1.00, 0.32, 0.14, and 1.00 using EDTA samples and 1.00, 0.29, 0.16, and 1.00 for the Stago Liatest assay, respectively. Three patients had significantly higher results for the Stago Liatest D-dimer assay compared with the Biosite Triage device although ultrasound scans were negative. Conclusion: The Biosite Triage D-dimer assay performed on either citrate or EDTA samples is comparable with the Stago Liatest laboratory D-dimer assay when used in conjunction with clinical pretest probability scoring and CUS for the exclusion of DVT. [source]

    Successful renal transplantation in the right iliac fossa 2 years after serious deep venous thrombosis in a patient with systemic lupus erythematosus

    Abstract Deep venous thrombosis (DVT) possibly occurs in the perioperative period, and induces serious complications such as a pulmonary embolism. On the other hand, allograft renal vein thrombosis leads to a high incidence of graft loss. We experienced a case in which a serious DVT occurred prior to renal transplantation; however, a successful renal transplantation in the right iliac fossa was performed after 2 years of anticoagulant therapy. It is suggested that the external iliac vein even after suffering from DVT can be anastomosed to an allograft vein successfully, when enough blood ,ow or a lower venous pressure is con,rmed. However, one should be aware of the risk factors and the adequate management of thrombosis in renal transplantation because of the serious complications of DVT and the poor prognosis of allograft vein thrombosis. [source]

    Asymptomatic deep vein thrombosis in advanced cancer patients: The value of venous sonography

    Nira Beck-Razi MD
    Abstract Purpose. Although guidelines for venous thromboembolism prevention are available, the implementation of anticoagulant prophylaxis in patients with advanced cancer has yet to be more clearly defined. We aim to determine the incidence of lower extremity deep vein thrombosis (DVT) diagnosed by Doppler sonography (USD) in asymptomatic nonambulatory patients with advanced cancer. Method. In a prospective study, 44 nonambulatory cancer patients with grade 3,4 World Health Organization performance status, asymptomatic for lower extremity DVT, underwent bilateral venous USD studies of the lower extremities. Different risk factors and laboratory data were registered and correlated with the incidence of DVT. Result. Asymptomatic DVT was detected in 15 of 44 patients (34%, 95% CI, 0.21,0.49). Twenty-three percent of all patients had isolated deep calf vein thrombi and 11% of all patients had thrombi in the proximal veins. The only significant risk factor was the number of metastatic sites. DVT was found in 4 of 23 (17.4%) patients with one metastatic site as opposed to 11 of 21 (52.3%) with two or more sites (p < 0.01). Conclusion. USD of the lower extremities detected asymptomatic DVT in 34% of advanced nonambulatory cancer patients and may serve as an additional decision-making tool in the consideration of anticoagulant therapy for this specific population. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source]

    Serial compression B-scan and Doppler sonography for the screening of deep venous thrombosis in patients with spinal cord injuries

    Alfried Germing MD
    Abstract Purpose To evaluate the usefulness of serial compression B-scan and Doppler sonography (US) in screening for deep venous thrombosis (DVT) of the lower extremities in patients with spinal cord injuries. Method Patients with paraplegia and tetraplegia due to spinal cord injuries were screened by a serial compression B-scan and Doppler US protocol for DVT of the bilateral lower extremities within the first 36 hours after admission, at day 7 and at day 21. In patients with DVT, a follow-up US examination was performed 3 weeks after diagnosis to assess thrombi distribution. Results Between January 2007 and March 2008, a total of 115 patients (75 males, 40 females), aged 19 to 85 years, were included. The first US examination documented a DVT in 44 cases (38.3%). After an initial negative scan, sonography after 7 days and 21 days showed DVT in 6 patients and 2 patients, respectively. Cumulative rate of DVT after the first 3 weeks was 45.2% (n=52). Follow-up US after 3 weeks in patients with DVT documented a complete recanalization in 19 patients (36.5%), no change in 12 patients (23.1%), and residual thrombi with partial recanalization in 21 patients (40.4%). Conclusion Our study supports the use of serial compression B-scan and Doppler US as a screening tool for DVT of the lower extremities in patients with spinal cord injuries early after injury. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source]

    Evaluating the effectiveness of a deep-vein thrombosis prophylaxis protocol in orthopaedics and traumatology

    Koray Unay MD
    Abstract Rationale, aims and objectives, To evaluate the effectiveness of the deep-vein thrombosis (DVT) prophylaxis protocol for adult patients in a general orthopaedics and traumatology clinic. Method, We followed the DVT prophylaxis protocol in 1326 (776 female, 550 male) of 2114 adult patients admitted to the Department of Orthopaedics and Traumatology in Goztepe Research and Training Hospital. They were followed for symptomatic DVT and possible complications of low-molecular-weight heparin (LMWH) therapy. A Doppler ultrasonography (US) was performed when DVT was suspected. The medical information treatment protocols of DVT patients were recorded. Results, Doppler US was performed in 58 patients with suspected DVT. Six of these patients were diagnosed with DVT. The side effects of LMWH were upper gastrointestinal bleeding (0.5%), widespread ecchymosis of the extremities (1.9%) and heparin-induced thrombocytopenia (0.16%). Conclusion, Symptomatic DVT occurrences were similar to those in medical literature; however, there were fewer side effects of LMWH than reported in literature. [source]

    Accuracy of Very Low Pretest Probability Estimates for Pulmonary Embolism Using the Method of Attribute Matching Compared with the Wells Score

    Jeffrey A. Kline MD
    Abstract Objectives:, Attribute matching matches an explicit clinical profile of a patient to a reference database to estimate the numeric value for the pretest probability of an acute disease. The authors tested the accuracy of this method for forecasting a very low probability of venous thromboembolism (VTE) in symptomatic emergency department (ED) patients. Methods:, The authors performed a secondary analysis of five data sets from 15 hospitals in three countries. All patients had data collected at the time of clinical evaluation for suspected pulmonary embolism (PE). The criterion standard to exclude VTE required no evidence of PE or deep venous thrombosis (DVT) within 45 days of enrollment. To estimate pretest probabilities, a computer program selected, from a large reference database of patients previously evaluated for PE, patients who matched 10 predictor variables recorded for each current test patient. The authors compared the outcome frequency of having VTE [VTE(+)] in patients with a pretest probability estimate of <2.5% by attribute matching, compared with a value of 0 from the Wells score. Results:, The five data sets included 10,734 patients, and 747 (7.0%, 95% confidence interval [CI] = 6.5% to 7.5%) were VTE(+) within 45 days. The pretest probability estimate for PE was <2.5% in 2,975 of 10,734 (27.7%) patients, and within this subset, the observed frequency of VTE(+) was 48 of 2,975 (1.6%, 95% CI = 1.2% to 2.1%). The lowest possible Wells score (0) was observed in 3,412 (31.7%) patients, and within this subset, the observed frequency of VTE(+) was 79 of 3,412 (2.3%, 95% CI = 1.8% to 2.9%) patients. Conclusions:, Attribute matching categorizes over one-quarter of patients tested for PE as having a pretest probability of <2.5%, and the observed rate of VTE within 45 days in this subset was <2.5%. ACADEMIC EMERGENCY MEDICINE 2010; 17:133,141 © 2010 by the Society for Academic Emergency Medicine [source]

    Cerebral Infarction in Conjunction With Patent Foramen Ovale and May-Thurner Syndrome

    David M. Greer MD
    ABSTRACT Stroke patients with paradoxical embolus mandate a search for deep venous thrombosis (DVT) in the lower extremities. Iliac vein compression, or May-Thurner syndrome, places certain patients at risk for development of DVT. The authors present 3 stroke patients with patent foramen ovale and paradoxical cerebral embolism, with demonstrated iliac vein compression as the presumed source of their embolus. May-Thurner syndrome should be considered a potential source of clot, as definitive therapy of this disorder can be curative. [source]

    Inhalable liposomes of low molecular weight heparin for the treatment of venous thromboembolism

    Shuhua Bai
    Abstract This study tests the feasibility of inhalable pegylated liposomal formulations of low molecular weight heparin (LMWH) for treatment of two clinical manifestations of vascular thromboembolism: deep vein thrombosis (DVT) and pulmonary embolism (PE). Conventional distearoyl- sn -glycero-3-phosphoethanolamine (DSPE) and long-circulating pegylated (DSPE,PEG-2000 and DSPE,PEG-5000) liposomes were prepared by hydration method. Formulations were evaluated for particle size, entrapment efficiency, stability, pulmonary absorption, anticoagulant, and thrombolytic effects in rats. Pulmonary absorption was monitored by measuring plasma antifactor Xa activity; anticoagulant and thrombolytic effects were studied by measuring reduction in thrombus weight and amount of dissolved radioactive clot in the blood, respectively. Pegylated liposomal were smaller and showed greater drug entrapment efficiency than conventional liposomes. All formulations produced an increase in pulmonary absorption and circulation time of LMWH upon first dosing. Three repeated dosings of conventional liposomes resulted in decreased half-life and bioavailability; no changes in these parameters were observed with pegylated liposomes. PEG-2000 liposomes were effective in reducing thrombus weight when administered every 48,h over 8 days. In terms of thrombolytic effects and dosing frequency, PEG-2000 liposomes administered via the pulmonary route at a dose of 100,U/kg were as effective as 50,U/kg LMWH administered subcutaneously. This paper suggests that inhalable pegylated liposomes of LMWH could be a potential noninvasive approach for DVT and PE treatment. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:4554,4564, 2010 [source]

    Patients with a first symptomatic unprovoked deep vein thrombosis are at higher risk of recurrent venous thromboembolism than patients with a first unprovoked pulmonary embolism

    M. J. KOVACS
    Summary.,Background:,Previous studies are mixed as to whether patients with unprovoked pulmonary embolism (PE) have a higher rate of venous thromboembolism (VTE) recurrence after anticoagulation is discontinued than patients with unprovoked deep vein thrombosis (DVT). Objectives:,To determine whether patients with unprovoked PE have a higher rate of VTE recurrence than patients with unprovoked DVT in a prospective multicenter cohort study. Patients/Methods:,Six hundred and forty-six patients with a first episode of symptomatic unprovoked VTE were treated with heparin and subsequent oral anticoagulation for 5,7 months, and were followed every 6 months for recurrent VTE after their anticoagulant therapy was discontinued. Results:,Of 646 patients, 194 had isolated PE, 339 had isolated DVT, and 113 had both DVT and PE. After a mean of 18 months of follow-up, there were 91 recurrent VTE events (9.5% annualized risk of recurrent VTE in the total population). The crude recurrent VTE rate for the isolated PE, isolated DVT and DVT and PE groups were 7.7%, 16.5% and 17.7%, respectively. The relative risk of recurrent VTE for isolated DVT vs. isolated PE was 2.1 (95% confidence interval 1.2,3.7). Conclusions:,This study has demonstrated that patients with a first episode of unprovoked isolated DVT are 2.1 times more likely to have a recurrent VTE episode than patients with a first episode of unprovoked isolated PE. These findings need to be considered when determining the optimal duration of anticoagulant therapy for patients with unprovoked VTE. [source]

    ORIGINAL ARTICLE: Venous thromboembolism and subsequent diagnosis of subarachnoid hemorrhage: a 20-year cohort study

    Summary.,Background:,Venous thromboembolism is a predictor of subsequent risk of ischemic stroke and intracerebral hemorrhage, but no data are available regarding its association with risk of subarachnoid hemorrhage. Objectives:,To examine this issue, we conducted a nationwide cohort study in Denmark. Patients and methods: Between 1977 and 2007, we identified 97 558 patients with a hospital diagnosis of venous thromboembolism and obtained information on risk of subsequent subarachnoid hemorrhage during follow-up in the Danish Registry of Patients. The incidence of subarachnoid hemorrhage in the venous thromboembolism cohort was compared with that of 453 406 population control cohort members. Results:,For patients with pulmonary embolism (PE), there was clearly an increased risk of subarachnoid hemorrhage, both during the first year of follow-up [relative risk 2.69; 95% confidence interval (CI), 1.32,5.48] and during later follow-up of 2,20 years (relative risk 1.40; 95% CI, 1.05,1.87). For patients with deep venous thrombosis (DVT) the risk was likewise clearly increased during the first year of follow-up (relative risk 1.91; 95% CI, 1.13,3.22), but not during later follow-up (relative risk 1.04; 95% CI, 0.81,1.32). Conclusions:,We found evidence that PE is associated with an increased long-term risk of subarachnoid hemorrhage. The two diseases might share etiologic pathways affecting the vessel wall or share unknown risk factors. [source]

    Effect of time of admission on compliance with deep vein thrombosis prophylaxis in a tertiary medical intensive care unit

    Summary.,Objective:,We sought to evaluate deep vein thrombosis (DVT) prophylaxis compliance according to time of admission in a medical intensive care unit (MICU). Methods:,This was a retrospective cohort study at a closed tertiary MICU. We classified patients into three groups (week days, weekends, and week nights), according to time of admission. An unweighted risk factor score (RFS) was calculated from 20 known risk factors. We defined DVT prophylaxis compliance as any type of prophylaxis (mechanical or pharmacologic) for RFS , 3 or both types of prophylaxis for RFS > 3. Non-compliance was defined as no prophylaxis or single-type prophylaxis for RFS > 3. Results:,We analyzed 105 admissions. Eighty (76.19%) patients received compliant DVT prophylaxis, and 25 (23.81%) patients received non-compliant regimens of whom 11 (10.48%) were not on any prophylaxis. DVT prophylaxis compliance was not different across the three admission groups. The non-compliant DVT prophylaxis group had a higher RFS (3.48 ± 2.1 vs. 2.25 ± 1.5; P = 0.011), a trend towards fewer female patients (40% vs. 60%; P = 0.079), and a higher percentage of admissions by interns at the first postgraduate year (PGY) level (28% vs. 5.4%; P = 0.01). Logistic regression revealed that only RFS and PGY level were independent predictors for compliance (P = 0.015 and 0.005 respectively). Time of admission was not a significant factor. Conclusions:,Time of admission did not influence DVT prophylaxis compliance. Compliance improved with higher PGY level and lower RFS. A higher level of knowledge probably explains the association with PGY level; however, we cannot explain the inverse relationship between RFS and compliance. [source]

    Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome

    S. R. KAHN
    Summary., The post-thrombotic syndrome (PTS) is a frequent and important complication of deep venous thrombosis (DVT). The diagnosis of PTS is based primarily on the presence of typical symptoms and clinical signs. In the 1990s, a clinical scale known as the Villalta scale was proposed as a measure that could be used to diagnose and classify the severity of PTS. The objective of the present paper was to review the published evidence on the measurement properties of the Villalta scale. Results of the review demonstrate that the Villalta scale is a reliable and valid measure of PTS in patients with previous, objectively confirmed DVT. The scale is acceptable to research subjects and research personnel, and shows responsiveness to clinical change in PTS. Aspects of the Villalta scale that merit further evaluation include test,retest reliability, more detailed assessment of ulcer severity and assessment of responsiveness across the full range of PTS severity. Research aimed at improving the measurement of PTS will also help to improve the overall validity of findings generated by clinical studies of PTS. [source]

    Differences in clinical presentation of deep vein thrombosis in men and women

    Summary.,Background:,As assessment of clinical pretest probability is the first step in the diagnostic evaluation of deep vein thrombosis (DVT), it is important to know if the clinical features of DVT are the same in men and women. Objectives:,To compare the prevalence and clinical characteristics of DVT, and the accuracy of clinical pretest probability assessment, between men and women with suspected DVT. Methods:,A retrospective analysis of individual patient data from three prospective studies by our group that evaluated diagnostic tests for a suspected first episode of DVT. Clinical characteristics, clinical pretest probability for DVT, and prevalence and extent of DVT was assessed in a total of 1838 outpatients. Results:,The overall prevalence of DVT was higher in men than in women (14.4% vs. 9.4%) (P = 0.001). The prevalence of DVT was higher in men than in women who were categorized as having a clinical pretest probability that was low (6.9% vs. 3.5%; P = 0.025) or moderate (16.9% vs. 8.7%; P = 0.04), but similar in patients in the high category (40.2% vs. 44.0%; P = 0.6). In patients diagnosed with DVT, swelling of the entire leg occurred more often (41.5% vs. 15.7%; P < 0.001), and thrombosis was more extensive (involvement of both popliteal and common femoral veins in 47.9% vs. 21.6%), in women than in men. Conclusions:,In outpatients with suspected DVT, the overall prevalence of thrombosis and the prevalence of thrombosis in those with a low or a moderate clinical pretest probability were higher in men than in women. [source]

    Prevalence of post-thrombotic syndrome following asymptomatic thrombosis in survivors of acute lymphoblastic leukemia

    S. KUHLE
    Summary.,Background:,Deep vein thrombosis (DVT) is a complication of treatment of acute lymphoblastic leukemia (ALL) in children but little is known about the long-term outcomes of these DVT. Objective:,To determine the incidence of post-thrombotic syndrome (PTS) in (i) children with ALL diagnosed with asymptomatic DVT using radiographic testing and (ii) an unselected group of ALL survivors. Methods:,Cross-sectional study in two populations. Group I comprised children in the Prophylactic Antithrombin Replacement in Kids with ALL treated with L-Asparaginase (PARKAA) study diagnosed with DVT by radiographic tests. Group II consisted of non-selected childhood ALL survivors <21 years. PTS was assessed using a standardized scoring sheet. Results:,Group I: 13 PARKAA patients (median age 12 years) were assessed, and 7 had PTS (54%; 95% CI, 25,81). All patients had collaterals, three also had increased arm circumference. Group II: 41 patients (median age 13 years) with a history of ALL were enrolled, and 10 had PTS (24%; 95% CI, 11,38). All patients had collaterals; five also had increased arm circumference. Conclusion:,There is a high incidence of PTS in survivors of childhood ALL with radiographically diagnosed asymptomatic DVT. A significant proportion of ALL survivors develop PTS, indicating previously undiagnosed DVT. [source]

    Bridging therapy in patients on long-term oral anticoagulants who require surgery: the Prospective Peri-operative Enoxaparin Cohort Trial (PROSPECT)

    A. S. DUNN
    Summary., Background:, The peri-operative management of patients on oral anticoagulants (OACs) is a common clinical problem. Our aim was to determine the incidence of major bleeding during peri-operative administration of treatment-dose enoxaparin and the impact of the extensiveness of the procedure on the risk of bleeding. Methods:, We performed a prospective cohort study of 260 patients at 24 North American sites on OACs for atrial fibrillation or a history of deep vein thrombosis (DVT) requiring invasive or surgical procedures whose treating physician felt that bridging therapy was required. Warfarin was withheld, and once-daily s.c. enoxaparin (1.5 mg kg,1) was given peri-operatively. Patients were followed for 28 days after OAC was therapeutic. Results:, Major bleeding was observed in nine of 260 patients (3.5%, 95% CI: 1.6,6.5). The bleeding risk varied markedly by extensiveness of procedure: the incidence of major bleeding for invasive procedures, minor surgery and major surgery was 0.7% (95% CI: 0.02,3.7), 0% (95% CI: 0,5.0), and 20.0% (95% CI: 9.1,35.7), respectively. There were five thromboembolic events in total (1.9%, 95% CI: 0.6,4.4). There were four arterial events (2.3%, 95% CI: 0.6,5.7) in 176 patients with atrial fibrillation, and one venous event (1.0%, 95% CI: 0.03,5.7) in 96 patients with prior DVT. Conclusions:, Bridging therapy with once-daily therapeutic-dose enoxaparin administered primarily in an outpatient setting has a low incidence of major bleeding for patients undergoing invasive procedures and minor surgery. Further studies are needed to optimize the bridging strategy for patients undergoing major surgery. [source]

    Ultrasound screening for asymptomatic deep vein thrombosis after major orthopaedic surgery: the VENUS study

    Summary.,Background:,Venography is currently used to assess the incidence of deep vein thrombosis (DVT) in dose-finding and confirmatory trials of new antithrombotic agents. Centrally adjudicated, complete compression ultrasound (CCUS) could be a non-invasive alternative to venography. Objectives:,A substudy of two, similarly designed, phase IIb trials of a novel, oral anticoagulant for the prevention of venous thromboembolism after elective hip or knee arthroplasty was undertaken to validate CCUS against venography. Patients/Methods:,Patients received study drugs until mandatory, bilateral venography was performed 7 ± 2 days after surgery. CCUS was performed within 24 h after venography by sonographers blinded to the venography result. Sonographers were trained and certified for the standardized examination and documentation procedure. Venograms and sonograms were adjudicated centrally at different sites by two independent readers; discrepancies between readers were resolved by consensus. Results:,A total of 1104 matching pairs of evaluable venograms and sonograms were obtained from the participants of the two trials (n = 1435): 19% of venograms and 20% of sonograms were not evaluable. The observed frequency of any DVT was 18.9% with venography and 11.5% with CCUS. Sensitivity of CCUS compared with venography was 31.1% for any DVT (95% confidence interval 23.4, 38.9), 21.0% (2.7, 39.4) for proximal DVT, and 30.8% (23.1, 38.6) for distal DVT. The figures for specificity were 93.0% (91.0, 95.1), 98.7% (98.0, 99.5), and 93.3% (91.5, 95.3), respectively. Conclusions:,Based on these results, centrally adjudicated CCUS will be unable to replace venography for DVT screening early after major orthopaedic surgery in studies evaluating anticoagulant drugs. [source]

    Association between asymptomatic deep vein thrombosis detected by venography and symptomatic venous thromboembolism in patients undergoing elective hip or knee surgery

    Summary.,Background:,Venography is commonly used to compare the efficacy of different thromboprophylaxis strategies for preventing deep vein thrombosis (DVT) in patients undergoing total hip replacement (THR) or total knee replacement (TKR). Methods:,We explored the relation between asymptomatic DVT and symptomatic venous thromboembolism (VTE) in patients undergoing THR or TKR treated with standard doses of enoxaparin (30 mg b.i.d. or 40 mg o.d.) by comparing the incidence of asymptomatic DVT in venographic studies with the incidence of symptomatic VTE in studies where venography was not performed. Results:,In 10 venographic studies involving 5796 patients, the incidence of asymptomatic DVT after THR was 13.2% [95% CI, 12.2,14.2%] and after TKR was 38.1% (95% CI, 35.5,40.8%). In two studies involving 3500 patients who did not undergo venography, the 90-day incidence of symptomatic VTE after THR was 2.7% (95% CI, 2.1,3.4%) and after TKR was 1.8% (95% CI, 0.9,2.7%). For every symptomatic VTE in THR studies where venography was not performed there were five asymptomatic DVTs in the venographic studies; for TKR, the ratio was 1:21. The incidence of asymptomatic DVT and the symptomatic VTE/asymptomatic DVT ratio was influenced by the venogram reading committee (Gothenburg vs. Hamilton: total DVT after THR, 19.5% vs. 8.7%, P < 0.0001; for TKR, 42.7% vs. 27.2%, P < 0.0001). Conclusions:,Comparisons across trials show a consistent relation between asymptomatic venographic DVT in patients undergoing elective THR or TKR surgery and symptomatic VTE in patients not undergoing venography. Differences exist in the strength of the relation depending on the type of surgery and the venogram reading committee. [source]

    Is it worth diagnosing and treating distal deep vein thrombosis?


    Summary., The standard diagnostic approach to suspected deep vein thrombosis (DVT) is serial lower limb compression ultrasound (CUS) of proximal veins. Although it only assesses the proximal veins, withholding anticoagulant treatment in patients with a negative CUS on day 1 and after 1 week has been proved safe. In particular, studies evaluating CUS limited to the proximal veins showed a good safety profile with a pooled estimate of the 3-month thromboembolic rate of 0.6% (95% CI, 0.4,0.9%) in non-anticoagulated patients. However, performing two lower limbs CUS is cumbersome and expensive. Recently, studies using a unique complete (proximal and distal) CUS showed a similar pooled estimate of the 3-month thromboembolic rate (0.3%; 95% CI, 0.1,0.6%) but distal DVTs accounted for as many as 50% of all diagnosed DVTs in those series. Comparing these studies may suggest that systematically searching for calf DVTs potentially doubles the number of patients given anticoagulant therapy and entails a risk of over-treatment. Admittedly, performing calf CUS is highly useful in diagnosing other conditions such as popliteal cyst, hematoma or muscle rupture. Performing a CUS limited to the popliteal site in the presence of calf pain may be not well accepted by the patient. However, the advantage of calf CUS in diagnosing venous thromboembolism appears to be at the least debatable. Data suggesting that anticoagulation is indicated for distal DVT are limited, and realizing systematic distal CUS entails a risk of over-treatment. There is an urgent need for randomized trials assessing the usefulness of anticoagulant treatment in distal DVT. [source]

    Diagnostic accuracy of D-dimer test for exclusion of venous thromboembolism: a systematic review

    Summary.,Background: The reported diagnostic accuracy of the D-dimer test for exclusion of deep vein thrombosis (DVT) and pulmonary embolism (PE) varies. It is unknown to what extent this is due to differences in study design or patient groups, or to genuine differences between D-dimer assays. Methods: Studies evaluating the diagnostic accuracy of the D-dimer test in the diagnosis of venous thromboembolism were systematically searched for in the MEDLINE and EMBASE databases up to March 2005. Reference lists of all included studies and of reviews related to the topic of the present meta-analysis were manually searched for other additional potentially eligible studies. Two reviewers independently extracted study characteristics using standardized forms. Results: In total, 217 D-dimer test evaluations for DVT and 111 for PE were analyzed. Several study design characteristics were associated with systematic differences in diagnostic accuracy. After adjustment for these features, the sensitivities of the D-dimer enzyme-linked immunofluorescence assay (ELFA) (DVT 96%; PE 97%), microplate enzyme-linked immunosorbent assay (ELISA) (DVT 94%; PE 95%), and latex quantitative assay (DVT 93%; PE 95%) were superior to those of the whole-blood D-dimer assay (DVT 83%; PE 87%), latex semiquantitative assay (DVT 85%; PE 88%) and latex qualitative assay (DVT 69%; PE 75%). The latex qualitative and whole-blood D-dimer assays had the highest specificities (DVT 99%, 71%; PE 99%, 69%). Conclusions: Compared to other D-dimer assays, the ELFA, microplate ELISA and latex quantitative assays have higher sensitivity but lower specificity, resulting in a more confident exclusion of the disease at the expense of more additional imaging testing. These conclusions are based on the most up-to-date and extensive systematic review of the topic area, including 184 articles, with 328 D-dimer test evaluations. [source]

    Type and location of venous thromboembolism in patients with factor V Leiden or prothrombin G20210A and in those with no thrombophilia

    Summary.,Background: Patients with factor (F) V Leiden or the prothrombin G20210A polymorphism are at increased risk of developing deep vein thrombosis (DVT). On the other hand, the risk of developing pulmonary embolism (PE) appears to be low in carriers of FV Leiden, perhaps because of a lower tendency to develop iliofemoral DVT than non-carriers. For prothrombin G20210A, data are scanty and controversial. Methods: The clinical manifestations (isolated DVT, DVT and PE, and isolated PE), the extension of DVT, and the presence of transient risk factors were retrospectively investigated in 115 patients with heterozygous FV Leiden, 87 with prothrombin G20210A and 200 with no thrombophilia marker. Results: Isolated symptomatic PE was less prevalent in patients with FV Leiden (6%) than in those with prothrombin G20210A (21%) and no thrombophilia (23%) (P > 0.0001). The rate of distal DVT was higher in patients with no thrombophilia (16% vs. 7% for FV Leiden and 6% for prothrombin G20210A) (P = 0.02). No difference in the incidence of PE from distal and proximal DVT, the extension of proximal DVT and the type of transient risk factors for venous thromboembolism (VTE) was found in the three groups. Patients with prothrombin G20210A had a younger age at their first VTE (24 years, P < 0.0001) and a higher rate of DVT accompanying PE (P = 0.04) than those with FV Leiden or no thrombophilia. Conclusions: Carriers of prothrombin G20210A, unlike those of FV Leiden, have an increased risk of developing isolated PE. This difference was not explained by a different rate of distal DVT, extension of proximal DVT, or distribution of transient risk factors in the two groups. Patients with prothrombin G20210A have more severe clinical manifestations than those with FV Leiden or no thrombophilia. [source]

    Elevated levels of soluble fibrin or D-dimer indicate high risk of thrombosis

    H. WADA
    Summary.,Background:,Fibrin-related markers such as soluble fibrin (SF) and D-dimer are considered useful for the diagnosis of thrombosis. However, the evidence for diagnosis of thrombosis by fibrin-related markers is not well-established. Objective:,To evaluate the cutoff values of D-dimer and SF in the diagnosis of thrombosis. Patients and Methods:,Plasma concentrations of SF and D-dimer were measured in 784 inpatients suspected of having thrombosis between 1 August 2003 and 31 December 2004, and then correlated with thrombosis. Results and Conclusions:,Plasma concentrations of D-dimer and SF were significantly higher in patients with disseminated intravascular coagulation (DIC), deep vein thrombosis (DVT) and cerebral thrombosis, compared with those in patients without thrombosis. When cutoff values of > 3.0 ,g mL,1 for D-dimer and > 6.0 ,g mL,1 for SF were used for the diagnosis, more than 50% of patients (with the exception of liver transplant patients and postoperative patients) had thrombosis. Receiver operating characteristic analysis showed that SF was more useful than D-dimer for the diagnosis of thrombosis (i.e. DVT and DIC). The cutoff value of D-dimer (7.87 ,g mL,1) was the same for DVT and DIC, while that of SF was slightly lower for DVT (7.05 ,g mL,1) than for DIC (8.60 ,g mL,1). Our findings suggest that high levels of plasma fibrin-related markers reflect high risk for thrombosis. [source]

    The utility of quantitative calf muscle near-infrared spectroscopy in the follow-up of acute deep vein thrombosis

    Summary.,Background:,To investigate patterns of venous insufficiency and changes in calf muscle deoxygenated hemoglobin (HHb) levels after an acute deep vein thrombosis (DVT). Methods:,A total of 78 limbs with an acute DVT involving 156 anatomic segments were evaluated with duplex scanning and near-infrared spectroscopy (NIRS) at 1, 3, 6 and 12 months. Venous segments were examined whether they were occluded, partially recanalized, and totally recanalized, and the development of venous reflux was noted. The NIRS was used to measure calf muscle HHb levels. Calf venous blood filling index (HHbFI) was calculated on standing, then the calf venous ejection index (HHbEI), and the venous retention index (HHbRI) were obtained after exercise. Results:,The segments investigated were the common femoral vein (CFV; 38 segments), femoral vein (FV; 37), popliteal vein (POPV; 44), and calf veins (CV; 37). At 1 year, thrombi had fully resolved in 67% of the segments, 27% remained partially recanalized, 6% were occluded. The venous occlusion was predominant in the FV (24%) at 1 year. On the contrary, rapid recanalization was obtained in CV than proximal veins at each examination (P < 0.01). Venous reflux was predominant in POPV (55%), followed by FV (19%), and no reflux was found in CV. At 1 year, the HHbFI in POPV reflux patients was significantly higher than those with resolution (0.19 ± 0.14, 0.11 ± 0.05 ,m s, P = 0.009, respectively). Similarly, there was a significant difference in the HHbRI between the two groups (3.08 ± 1.91, 1.42 ± 1.56, P = 0.002, respectively). In patients with FV occlusion, the value of HHbRI was significantly higher than those with complete resolution (2.59 ± 1.50, 1.42 ± 1.56, P = 0.011, respectively). Conclusions:,The lower extremity venous segments show different proportions of occlusion, partial recanalization, and total recanalization. The CV shows more rapid recanalization than proximal veins. The NIRS-derived HHbFI and HHbRI could be promising parameters as the overall venous function in the follow-up of acute DVT. These findings might be very helpful for physician in detecting patients who require much longer follow-up studies. [source]

    Incidence of venous thromboembolism following major abdominal surgery: a multi-center, prospective epidemiological study in Japan

    M. SAKON
    Summary.,Background:,Venous thromboembolism (VTE) has been considered to be a rare surgical complication in Japan. Aim:,To investigate the incidence and risk factors of VTE in Japanese patients undergoing major abdominal surgery. Methods:,A prospective, multi-center epidemiological study was conducted from December, 2001 to August 2002 in 39 medical institutes throughout Japan. A total of 173 patients with general (n = 128), gynecologic (n = 23), and urologic (n = 22) surgery were analyzed. For the diagnosis of deep vein thrombosis (DVT), bilateral venography was performed in all patients. Lung ventilation/perfusion scintigraphy was carried out in patients suspected of pulmonary thromboembolism (PTE). Results:,There were 36 patients with distal DVT (20.8%) and five patients with proximal DVT (2.9%). One patient was diagnosed as PTE. Overall, VTE was diagnosed in 42 patients (24.3%). By univariate analysis, only age (60 years or older) was identified as a significant risk factor in the whole study population. When analyzed by the stepwise multiple logistic regression model, female gender, operation site, age, and operation time were four risk factors found to be significant. The incidence of VTE was closely related to the number of risk factors that patients had. As many as 44% of patients with three or four risk factors developed VTE while those with one or two risk factors showed about a 17% incidence of VTE. Four patients lacking any risk factors did not develop VTE. Conclusions:,Venous thromboembolism is common in Japanese patients undergoing major abdominal surgery. Pharmacologic thromboprophylaxis is considered essential, particularly in those patients with multiple, potential risk factors. [source]

    Combined use of clinical pretest probability and D-dimer test in cancer patients with clinically suspected deep venous thrombosis

    Summary.,Background: The value of the D-dimer (DD) test in combination with the clinical pretest probability (PTP) has not been evaluated in cancer patients with suspected deep vein thrombosis (DVT), whereas this group of patients usually accounts for 10,25% of clinically suspected DVT. Methods: A cohort of 2066 consecutive patients with clinically suspected DVT was investigated. Patients were judged to be positive or negative for DVT according to the outcomes of serial compression ultrasound and a 3-month follow-up period with imaging test verification of the symptomatic cases. Diagnostic accuracy indices of the DD test according to the PTP score were assessed in patients with and without cancer. Results: Of the cohort, 244 (11%) were known to have cancer at presentation. A venous thromboembolic event was diagnosed in 41% of the patients with cancer and in 22% of the patients without malignancy. Among the cancer patients, 17% were considered to have a low PTP, 35% a moderate and 41% a high PTP. The negative predictive value (NPV) of the DD test was 100% (95%CI, 85,100) and 97% (95% CI, 88,99) among cancer patients with low PTP or low-moderate PTP. In the absence of malignancy, the corresponding NPV were 98% and 97%, respectively. The specificity of the DD test progressively decreased moving from the low to the higher PTP. Conclusions: In cancer patients with clinically suspected DVT, a negative DD might be useful in excluding the diagnosis within the low or low-moderate PTP groups. More studies are warranted to confirm these findings. [source]