Acute DVT Research Articles

Predictive value of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio for acute deep vein thrombosis after total joint arthroplasty: a retrospective study

BackgroundDeep vein thrombosis (DVT) is a common and severe complication of total joint arthroplasty (TJA). Inflammation has been proved to play a role in DVT. The neutrophil to lymphocyte ratio (NLR) and the platelet to lymphocyte ratio (PLR) are biomarkers for systemic inflammation. The aim of the study is to investigate the predictive value of NLR and PLR for acute TJA-induced DVT.MethodA total of 773 patients who underwent primary TJA in our hospital were included in this retrospective study. Venography was performed routinely after the surgery to define acute DVT. NLR and PLR before and after operation were calculated according to the blood routine test. Multiple logistic regression analyses and ROC curve analyses were performed to assess the association of NLR and PLR with TJA-induced DVT.ResultsOne hundred twenty out of 773 patients (15.5%) were diagnosed with DVT by venography. In patients with DVT, preoperative NLR (P = 0.030) and postoperative NLR (P = 0.015) were significantly higher but postoperative PLR (P = 0.002) was significantly lower. Multiple logistic regression analyses indicated that age (OR = 1.05, P < 0.005), gender (OR = 0.47, P = 0.005), BMI (OR = 1.06, P < 0.014), preoperative NLR (OR = 1.11, P < 0.035), postoperative NLR (OR = 1.20, P < 0.001), and PLR (OR = 0.99, P < 0.001) were independently associated with DVT. However, the ROC curve analysis demonstrated the specificity and sensitivity of NLR or PLR in predicting DVT were low.ConclusionAlthough the present study demonstrated significant association of perioperative NLR or PLR with acute TJA-induced DVT, NLR or PLR cannot predict TJA-induced DVT accurately.

Bilateral Phlegmasia Cerulea Dolens After Warfarin Reversal for Acute Rectal Bleeding: A Case Report

BackgroundDeep vein thrombosis (DVT) is a common disease that is diagnosed in approximately 1 in 1000 adults annually. Extensive DVT can lead to life- or limb-threatening diagnoses such as phlegmasia cerulea dolens (PCD), phlegmasia alba dolens, and venous gangrene. PCD, also known as massive iliofemoral venous thrombosis, is rare, and a severe complication of DVT. Case ReportWe report a case of a 94-year-old bedridden woman with past medical history of dementia, hypertension, pulmonary embolism, DVT, and atrial fibrillation. The patient was admitted to the hospital for bright red blood per rectum and an elevated international normalized ratio (INR) of 5.7. On admission, her dose of warfarin was suspended and she was given 4 units of fresh frozen plasma as well as 10 mg of i.v. vitamin K. She was discharged home with an INR normalized to 1.3 and cessation of her rectal bleeding. At discharge, she was not restarted on warfarin, nor was any bridging therapy used. The patient returned to the Emergency Department a week later for worsening pain and bluish discoloration of her bilateral lower extremities. An ultrasound (US) examination showed that she had developed bilateral PCD, after INR reversal. Why Should an Emergency Physician Be Aware of This?Emergency physicians commonly care for patients who present with acute DVT or treat patients on anticoagulant therapy who require cessation of medications or administration of prothrombotic agents to reverse bleeding. Cases of extensive clot burden leading to PCD have been reported in the literature, however, reports of bilateral PCD secondary to cessation of warfarin have been scarce. PCD should be considered carefully as one of the complications in warfarin reversal, as it requires immediate attention and surgical intervention to prevent limb loss.

Prevalence of lower limb deep venous thrombosis among adult HIV positive patients attending an outpatient clinic at Mulago Hospital

BackgroundDeep venous thrombosis (DVT) and its major complication pulmonary embolism (PE) are collectively known as venous thromboembolism. In Uganda, the prevalence of DVT among HIV patients has not been previously published. The aim of the study was to determine the prevalence and sonographic features of lower limb deep venous thrombosis among HIV positive patients on anti-retroviral treatment (ART).MethodsThis was a cross sectional study in which HIV positive patients on ART were recruited from an out-patient HIV clinic at Mulago National Referral Hospital. Patients were randomly selected and enrolled until a sample size of 384 was reached. Study participants underwent compression and Doppler ultrasound studies of both lower limb deep veins using Medison Sonoacer7 ultrasound machine.ResutsWe found a prevalence of DVT of 9.1% (35 of 384 participants) among HIV patients on ART. The prevalence of latent (asymptomatic) DVT was 2.3%. Among 35 patients with DVT, 42.8% had chronic DVT; 31.1% had acute DVT and the rest had latent DVT. Among the risk factors, the odds of occurrence of DVT among patients with prolonged immobility were 4.81 times as high as in those with no prolonged immobility (p = 0.023; OR = 4.81; 95% CI 1.25–18.62). Treatment with second line anti-retroviral therapy (ART) including protease inhibitors (PIs) was associated with higher odds of DVT occurrence compared with first line ART (p = 0.020; OR = 2.38; 95% CI 1.14–4.97). The odds of DVT occurrence in patients with a lower CD4 count (< 200 cells/µl) were 5.36 times as high as in patients with CD4 counts above 500 cells/µl (p = 0.008). About 48.6% patients with DVT had a low risk according to Well’s score.ConclusionDVT was shown in nearly 10% of HIV patients attending an out-patient clinic in an urban setting in Uganda. Risk factors included protease inhibitors in their ART regimen, prolonged immobility, and low CD4 count (< 200 cells/µl). Clinicians should have a low threshold for performing lower limb Doppler ultrasound scan examination on infected HIV patients on ART who are symptomatic for DVT. Therefore, clinicians should consider anti-coagulant prophylaxis and lower deep venous ultrasound screening of patients who are on second line ART regimen with low CD4 cell counts and/or with prolonged immobility or hormonal contraception.

Effect of Punarnavadi Mandoor and Shiva Gutika in Acute Deep Vein Thrombosis - A Case Report

Objectives: To minimise the dose of Anti-platelet drugs and to treat the acute case of DVT through Ayurvedic oral medications. Methods: The present diagnosed case of DVT approached to OPD of KLE BMK Ayurveda Hospital with a complaints of swelling and pain in the calf muscle of the left lower limb associated with reddish brown discoloration in the foot and occasionally nasal and gum bleeding was treated consequently for 5 months with Punarnavadi Mandoor and Shiva Gutika orally. Results: There is significant decrease in the symptoms of DVT and also major changes seen in Venous Colour Doppler study of the left lower limb. Conclusion: Acute DVT is caused by a blood clot in a deep vein and can be life threatening as it may leads to serious complication like pulmonary embolism which can be cured through Ayurvedic oral medications.

Acute iliofemoral DVT in the presence of May-Thurner syndrome.

Acute iliofemoral DVT in the presence of May-Thurner syndrome.

Abstract No. 203 - Prophylactic IVC filter placement in bariatric surgery patients: initial results from a prospective filter registry

Bariatric surgery patients are at moderate to high risk for VTE (1), but potential risks versus benefits of IVC filters in this group remain unclear (2). Indwelling filters may increase risk of VTE (3), and removal of filters in obese patients can be challenging (3). This study evaluated the incidence of VTE in bariatric patients receiving prophylactic IVC filters, their risk of filter-related complications, and outcomes from attempted filter retrieval. Over 4 years, 100 patients receiving an IVC filter prior to bariatric surgery were prospectively enrolled in a single-center IRB-approved study. Filters were placed if patients had BMI>50 kg/m2 and/or VTE risk factors per ASMBS guidelines (1), and all received mechanical (SCDs) and chemo-prophylaxis (UFH/LMWH). There were 29 men, 71 women, mean age = 49.0 ± 10.7 y; mean BMI = 58.0 ± 9.3. Retrievable filters were used (89 Gunther Tulip, 4 Option, 4 Denali, 2 ALN, 1 Celect) and patients underwent Roux-en-Y gastric bypass (n = 87) or sleeve gastrectomy (n = 13). All were contacted for follow-up and filter retrieval was attempted when no longer needed. All data were captured using REDCap. Postsurgical DVT occurred in 4(4%) (95%CI:1.0-10.0), at median 50 d (range: 17-94), and 1 patient (1%) (95%CI:0.03-5.0) developed acute low-risk PE at 23 days post-op, prior to filter removal. All VTE patients were successfully managed with therapeutic anticoagulation alone except one who also required thrombolysis to resolve IVC and iliofemoral DVT. Average filter dwell time was 146 d (range: 26-1548) and there were no major filter-related complications (0%). Retrieval was attempted in 96/100(96%) and successful in 96/96(100%). 28/96(29%) required advanced techniques for filter removal, and there were no major procedural complications (0%). Mean follow-up was 459.8 ± 407.7 days and 2 developed acute DVT > 1 year after filter retrieval, successfully treated with anticoagulation. Prophylactic IVC filters in combination with mechanical and chemoprophylaxis may help prevent life-threatening post-op PE in select bariatric surgery patients. The risk of filter-related complications was low, and retrieval success was high with adjunctive use of advanced techniques.

A Retrospective Study of Venous Thromboembolism in Acute Leukemia Patients during Prolonged Hospital Stay. the Princess Margaret Cancer Centre Experience

▪BackgroundThe role of thromboprophylaxis in solid organ malignancies is well established. Hematologic malignancies can also be associated with a considerable risk of thromboembolic complications. The incidence of these events is variable and is influenced by multiple factors. Limited data are available regarding the incidence of venous thromboembolism (VTE) in hospitalized acute leukemia (AL) patients. The management of symptomatic VTE in patients with AL can be challenging due to the increased risk of thrombocytopenia-related bleeding.MethodsThe Discharge summary Database (DAD) was used to extract post-admitted PE and DVT volumes in AL patients admitted to Princess Margaret Cancer Centre from 2007-2016. ICD-10-CA diagnosis codes for acute leukemia, and both PE and DVT events, were used. Only patients diagnosed with VTE at least 48 hours post-admission were included to restrict the cohort to patients that developed VTE during their admission.ResultsWe analyzed a total of 10,041 patients that were admitted to Princess Margaret Cancer Centre during the 2007-2016 period. (Table 1) Of these, 7759 had a solid tumor diagnosis (271 VTE events, 3.4%) and 2282 patients had AL (1675 AML, 464 ALL, 144 APL). The AL patients (AML, ALL, APL) admitted to our Centre for chemotherapy or for the management of complications were further evaluated to determine VTE incidence and to evaluate its management in this setting. As of September 2012, patients with solid tumors treated at our Centre received standard thromboprophylaxis as part of an institutional in-patient (VTE) prophylaxis policy (IPP) that reduced the incidence of VTE from 4.8% (219/4520) to 1.6% (3239/52) before and after the policy was initiated, respectively. AL patients are not given prophylactic anticoagulation. 37 AL patients (22 AML, 10 ALL, and 5 APL; overall incidence 1.6%) developed symptomatic VTE (DVT only 23, PE only 8, DVT + PE 6). VTE was reported as central venous catheter related in 12/37 patients (32.4%). PE was detected in all cases by CT-PE. Median age of VTE patients was 53 years (range 32-77), with a median hospital stay of 35 days (range 2-144). Chemotherapy was given to 26 of the 37 patients that developed VTE, with 20 receiving initial induction chemotherapy. 17/37 (46%) patients had PLT<50.000/mm3 at VTE diagnosis. Full dose low molecular weight heparin with platelet transfusion support was used to treat 35/37 patients with acute VTE during the first month of treatment. 2/37 did not receive anticoagulation due to ongoing active bleeding. None of the treated patients experienced major bleeding.ConclusionsIn our experience, the incidence of VTE in AL patients during prolonged hospital stay is relatively low, raising questions about the need for routine VTE prophylaxis in this group. The relatively increased risk of VTE in AL patients receiving chemotherapy (particularly, induction chemotherapy), should prompt particular scrutiny in symptomatic patients. [Display omitted] DisclosuresSchuh:Amgen: Membership on an entity's Board of Directors or advisory committees. Yee:Novartis Canada: Membership on an entity's Board of Directors or advisory committees, Research Funding. Gupta:Incyte Corporation: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Schimmer:Novartis: Honoraria.

Inferior Vena Cava Filter - Appropriate Use and Retrieval

Inferior vena cava (IVC) filters, first introduced in 1998, have been utilized to reduce risk of pulmonary embolism (PE) in the setting of an inability to anticoagulate patients. The use of IVC filters has increased and continues to rise, especially with the introduction of retrievable IVC filters. Since their initial introduction, guidelines have been developed on the appropriate use of IVC filters. According to the American College of Chest Physicians (ACCP), the use of an IVC filter is limited to patients with an absolute contraindication to therapeutic anticoagulation or failure or complication of anticoagulation in the setting an acute proximal venous thrombus. Relative indications for IVC filter placement include high clot burden in setting of low cardiopulmonary reserve, high risk patients, or severe trauma without documented thrombosis. In 2010, the FDA announced a safety communication recommending removal of retrievable IVC filters due to reports of several adverse clinical outcomes associated with retained filters including thrombus formation, recurrent PE, filter migration, erosion or perforation through the IVC wall, and filter fracture with fragment embolization. In 2014, the FDA recommended removal of the IVC filter within 2 months after filter placement if the patient's risk of thrombosis had passed.In this retrospective analysis of IVC filter management, we reviewed indications for placement according to current guidelines as set by the ACCP, initiation of appropriate anticoagulation, complication rates, and retrieval rates. In addition, we compared the data prior to the FDA recommendations in late 2014 and data after the recommendations to determine if there was a change in practice.After reviewing 179 patients, 89 patients in 2014 and 90 patients in 2015, who underwent IVC filter placement, only 81% (N=145) of patients had appropriate indications for IVC filter placement and 30% (N=54) of patients had inappropriate anticoagulation after IVC filter placement, given as prophylactic dosing of low molecular weight heparin. A comparison of retrieval rates prior to and after the FDA warning, showed a 19% (60% in 2014 vs 79% in 2015) improvement in IVC filter removals. There was an 11% complication rate, mainly related to IVC filter related acute DVT or IVC occlusion.A root cause analysis specifically for inappropriate IVC filter placement and appropriate anticoagulation and determined that familiarity of the guidelines and non-evidence based recommendations from consultants were major factors. Based on the analysis, we next plan to utilize the electronic health record system to help clinicians understand indications and when to initiate appropriate anticoagulation, with the opportunity for hematology consultants to be involved in situations that do not clearly fit within published guidelines. DisclosuresNo relevant conflicts of interest to declare.

Pharmacomechanical thrombectomy for iliofemoral deep vein thrombosis.

Deep venous thrombosis (DVT) occurs in approximately one in 1000 adults every year, and has an annual mortality of 14.6%. In particular, iliofemoral DVT can lead to recurrent thrombosis and post-thrombotic syndrome (PTS), a painful condition which can lead to chronic venous insufficiency, oedema, and ulceration. It causes significant disability, impaired quality of life, and economic burden. Early thrombus removal techniques have been advocated in patients with an iliofemoral DVT in order to improve vein patency, prevent valvular dysfunction, and reduce future complications, such as post-thrombotic syndrome and venous ulceration. One such technique is pharmacomechanical thrombectomy, a combination of catheter-based thrombectomy and catheter-directed thrombolysis. To assess the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein. The Cochrane Vascular Information Specialist searched the Specialised Register (last searched December 2015) and the Cochrane Register of Studies (last searched December 2015). We searched clinical trials databases for details of ongoing or unpublished studies and the reference lists of relevant articles retrieved by electronic searches for additional citations. Randomised controlled trials in which patients with an iliofemoral deep vein thrombosis were allocated to receive pharmacomechanical thrombectomy versus anticoagulation, mechanical thrombectomy, thrombolysis (systemic or catheter directed thrombolysis), or other endovascular techniques for the treatment of iliofemoral DVT. At least two review authors independently assessed studies identified for potential inclusion. We found no randomised controlled trials that met the eligibility criteria for this review. We identified one ongoing study. There were no randomised controlled trials that assessed the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein that met the eligibility criteria for this review. Further high quality randomised controlled trials are needed.

TCT-798 Comparison of Cathter Guided Thrombolysis And Ultrasound Accelerated Thrombolysis For The Treatment of Acute Ileo-femoral DVT

TCT-798 Comparison of Cathter Guided Thrombolysis And Ultrasound Accelerated Thrombolysis For The Treatment of Acute Ileo-femoral DVT

Spontaneous left iliac vein rupture — case report

Spontaneous iliac vein rupture is an uncommon cause of retroperitoneal haematoma. Most common concomitant pathology reported was deep vein thrombosis or thrombophlebitis and followed by May-Thurner Syndrome. In this particular case, we observed findings parallel to literature. A 61-year-old female patient complaining of abdominal and back pain was admitted to the emergency room. She was a smoker and except that medical history revealed only chronic obstructive pulmonary disease. Also, she had no history of trauma. She suffered from sudden left abdominal and back pain without evident cause. On arrival, her vitals were normal. An abdominopelvic computed tomography (CT) showed large haematoma in the lower abdominal cavity. Retroperitoneal exploration revealed large haematoma and left external iliac vein rupture. The vein was repaired primarily. Postoperative follow-up visit at one month after surgery showed that the patient was doing well. Iliac vein rupture should be taken into account in middle-aged or elderly women with acute onset abdominal pain and acute DVT.

Patients With a History of Idiopathic Deep Venous Thrombosis Have Long-Term Increased Levels of Inflammatory Markers and Markers of Endothelial Damage.

Although the role of inflammation in DVT has been investigated in different studies, there is no definite answer as to whether increased systemic inflammation is the cause or the consequence of DVT. To follow inflammatory parameters in a cohort of patients with idiopathic DVT. Out of 49 patients with an acute idiopathic DVT, which were investigated four months after an acute episode (DEVTA 1), 43 patients were included in the follow-up study investigating inflammatory markers and hemostatic markers of endothelial damage five years after an acute DVT (DEVTA 2). A control group consisted of 43 sex and age matched healthy subjects (CONTROLS). The levels of inflammatory markers were significantly higher in DEVTA 2 in comparison to CONTROLS: tumor necrosis factor alpha 2.0 pg/mL (1.1-2.3) vs 1.3 pg/mL (0.8-1.9), p < .001, high sensitivity C-reactive protein 3.2 mg/L (1.5-5.2) vs 1.7 mg/L (0.9-3.0), p = .008, interleukin-6 (IL-6) 2.7 pg/mL (2.0-3.5) vs 2.1 pg/mL (1.5-2.6), p = .025, IL-8 5.0 pg/mL (3.6-7.3) vs 2.4 pg/mL (1.8-2.8), p < .001. IL-10 was significantly decreased (0.9 pg/mL (0.7-1.8) vs 1.8 (1.5-2.2), p < .001. Most of the proinflammatory markers remained elevated in the DEVTA 2 in comparison to DEVTA 1. Markers of endothelial damage were higher in DEVTA 2 in comparison to CONTROLS and higher than in DEVTA 1. Patients with idiopathic DVT have long-term increased inflammatory markers and markers of endothelial damage. These findings favor the hypothesis that inflammation is a cause and not merely a consequence of acute DVT.

Long-term Anticoagulation With Rivaroxaban for Preventing Recurrent VTE: A Benefit-Risk Analysis of EINSTEIN-Extension

Short-term anticoagulant treatment for acute DVT or pulmonary embolism (PE) effectively reduces the risk of recurrent disease during the first 6 to 12months of therapy. Continued anticoagulation often is not instituted because of the perception among physicians that the risk of major bleeding will outweigh the risk of new venous thrombotic episodes. The authors performed a benefit-risk analysis by using the randomized EINSTEIN-Extension trial, which compared continued rivaroxaban with placebo in 1,197patients with symptomatic DVT or PE who had completed 6 to 12months of anticoagulation and in whom physicians had equipoise with respect to the need for continued anticoagulation. One-year Kaplan-Meier rates and rate differences of recurrent VTE and major bleeding were calculated. Benefits and risks were assessed using rate differences scaled to a population size of 10,000 patients treated for 1 year. Recurrent VTE occurred in eight recipients of rivaroxaban and 42 patients receiving placebo. In a population of 10,000 patients treated for 1 year, rivaroxaban treatment would have resulted in 665 (95%CI, 246-1,084) fewer recurrent VTEs than would placebo (number needed to treat= 15). Major bleeding occurred in four (0.7%) and zero patients, respectively. Rivaroxaban treatment would have resulted in 68 (95%CI, 2-134) more major bleeding events than would placebo (number needed to harm= 147). Kaplan-Meier analysis showed early recurrent VTE reduction with rivaroxaban that continued to improve throughout treatment; major bleeding increased gradually, plateauing at approximately 100days. A clinically important benefit and a favorable benefit-risk profile of continued rivaroxaban anticoagulation was observed. ClinicalTrials.gov; No.: NCT00439725; URL: www.clinicaltrials.gov.

Arrive: A retrospective registry of Indian patients with venous thromboembolism.

Background and Aim:There is lack of substantial Indian data on venous thromboembolism (VTE). The aim of this study was to provide real-world information on patient characteristics, management strategies, clinical outcomes, and temporal trends in VTE.Subjects and Methods:Multicentre retrospective registry involving 549 medical records of patients with confirmed diagnosis of VTE (deep vein thrombosis [DVT] confirmed by Doppler ultrasonography; pulmonary embolism [PE] by computed tomography, pulmonary angiography and/or V/Q scan) from 2006 to 2010 at three Indian tertiary care hospitals.Results:Acute DVT without PE, acute DVT with PE, and PE alone were reported in 64% (352/549), 23% (124/549), and 13% (73/549) patients, respectively. Mean age was 47 (±16) years, and 70% were males. H/o DVT (34%), surgery including orthopedic surgery (28%), trauma (16%), and immobilization >3 days (14%) were the most common risk factors for VTE. Hypertension (25%), diabetes (19%), and neurological disease (other than stroke) (8%) were the most common co-morbidities. Most (94%) were treated with heparin alone (82%) or fondaparinux (2%) for initial anticoagulation; low molecular weight heparin alone (5%) or warfarin/acenocoumarol (76%) for long-term anticoagulation. Anticoagulant treatment was stopped because of bleeding in 2% (9/515) patients. Mortality was 7% among patients diagnosed with VTE during hospital stay versus 1% in those hospitalized with diagnosed VTE. The annual incidence of DVT (±PE) increased from 2006 to 2010.Conclusion:Acute DVT alone was responsible for the substantial burden of VTE in Indian patients. Bleeding was not the limiting factor for anticoagulant treatment in most patients.

The 2005 Caprini Score Predicts Both Baseline Venous Thromboembolism Risk and Effectiveness of Chemoprophylaxis: A Meta-Analysis of 13,412 Surgical Patien

Conclusions: Apixaban is less effective in reducing thrombus burden than enoxaparin at 2and 14-day time points in this nonstasis murine model of DVT. This may be due to anti-inflammatory pleiotropic effects of enoxaparin that apixaban may not have in acute DVT. Further study is ongoing to determine whether vein wall remodeling is affected by Xa inhibition and whether this is an effect of apixaban itself or a class effect of anti-Xa inhibitors.

The Diagnosis and Management of Early Deep Vein Thrombosis.

The diagnosis and management of an acute DVT is difficult and mistakes are often made. The cost to the National Health Service (NHS) of litigation arising from failure to diagnose and treat DVT early is substantial. Clinical diagnosis alone is often unreliable and a large proportion of DVT occurring in hospital are asymptomatic. In the United Kingdom, clinical scoring systems, D-dimer and ultrasound (US) imaging have all been adopted to aid diagnosis via DVT pathways. These pathways aim to exclude DVT only and often fail to actually address the cause of the symptoms once DVT is eventually cleared.

Increased D-Dimer Levels and Residual Venous Thrombosis Are Associated with Late Recurrence of Deep Venous Thrombosis

Background: Many patients present new thrombotic events even long-time after the first thrombotic episode and risk factors for recurrence in these cases are not fully elucidated.Aim: To evaluate the risk of late recurrence of thrombosis after a first DVT episode.Methods: This is a prospective observational study. We evaluated the association of D-dimer (DD) levels and persistent residual venous thrombosis (RVT), by Doppler ultrasound, with the occurrence of new thrombotic events long-time after the acute DVT episode.Results: Fifty-six patients were enrolled for the study. For all patients, DVT episode occurred more than 12 months apart from the enrollment day. Median follow-up was 28 months. During the follow-up time, 10 patients presented thrombosis recurrence. Patients who suffered DVT recurrence had higher DD levels than those who did not had recurrence (median= 0.99 vs 0.40, respectively). The best cut-off value to discriminate those at risk for recurrence was DD > 0.63mg/L (area= 0.7380 95%CI= 0.5800 to 0.8961, P=0.01). Recurrence occurred in 27.7% of patients with previous DD>0.63mg/L and in 5.9% of patients with previous DD< 0.63mg/L (relative risk = 6.46; 95%CI 1.36- 30.52, P=0.007). New thrombosis events occurred only in patients with previously documented RVT, mainly in patients with hypoechoic RVT. During follow-up, new thrombotic events were diagnosed in 75% of patients with hypoechoic RVT. The relative risk for recurrence according to the presence of RVT was 9.129 (95% CI= 2.60-32.02, P<0.001). The presence of RVT also modified the effect of DD on the recurrence risk. Patients with DD > 0,63mg/L but without RVT had similar risk of recurrence than those with DD< 0.63mg/L, whereas the risk for recurrence increased in 14-15 times in patients with RVT.Conclusion: These results suggests that the persistence of residual thrombosis combined with high levels of DD, long-time after the acute DVT, are risk factors associated with late thrombosis recurrence. DisclosuresNo relevant conflicts of interest to declare.

Chronic IVC Occlusion Predisposing to Acute Lower Extremity DVT in Children

Congenital atresia of the inferior vena cava (IVC) is a known risk factor for spontaneous lower extremity thrombosis in adults. However, little is known about the incidence of IVC occlusion and its relationship to spontaneous lower extremity thrombosis in children. We reviewed the medical records of consecutive patients with IVC occlusion and lower extremity DVT who presented to our institution between 2008 and 2015. Data were reviewed for risk factors for thrombosis, treatment, and outcomes including recurrent thrombosis, bleeding complications, and post-thrombotic syndrome. This represents the largest reported analysis of previously healthy pediatric patients with occult chronic IVC occlusion presenting with unprovoked acute lower extremity thrombosis. Ten patients aged 13 to 18 years (median age 16.5yrs, 90% male) presenting with acute lower extremity thrombosis were found to have chronic occlusion of the IVC. One patient presented with pulmonary embolism. Seven patients underwent site-directed thrombolysis, and 3 patients received anticoagulation alone. All patients had persistent IVC occlusion regardless of treatment. Two patients had recurrent thrombosis while on anticoagulation. There were no provoking factors identified that preceded the presentation of acute lower extremity thrombosis, and none had predisposing risk factors that could explain the IVC occlusion. Four patients had a negative thrombophilia work up. Five had mild thrombotic risk factors such as heterozygosity for Factor V Leiden or elevated factor VIII levels. Only one patient had a significant thrombophilic risk factor, familial mild protein C deficiency. Five patients had post thrombotic syndrome based on standardized scoring tools. All patients remain on indefinite anticoagulation. This case series suggests that chronic IVC occlusion increases the risk of unprovoked lower extremity thrombosis and pulmonary embolism in healthy children with resultant long-term complications. It also highlights the importance of imaging the IVC in young patients with unprovoked or minimally provoked iliofemoral DVT. Indefinite anticoagulation in patients presenting with unprovoked thrombosis secondary to IVC occlusion should be considered. DisclosuresNo relevant conflicts of interest to declare.

Early Outcomes Following Endoluminal Deep Venous Reconstruction Using Dedicated Venous Stents

ObjectivesEvaluate early outcomes following endoluminal stenting using first-generation dedicated venous stents.MethodsPatients undergoing deep venous reconstruction using venous stents between 2012-2015 were identified. Duplex ultrasonography was used to assess sent patency at 1d, 2wks, 3mths, 6mths and yearly following intervention. Venous Disability Scores (VDS) and Villalta Scores (VS) taken before and after intervention (6wks, 6mths, yearly) were calculated.Results347stents were inserted in 140pts (median age 39yrs, 80 female) with median follow-up 16mths (1-38mths). Overall 1yr primary, primary-assisted and secondary patency rates were 67%, 80% and 82% respectively. The 1yr re-intervention rate was 30% with 16% occurring within two-weeks.57pts had stenting of residual stenoses after catheter-directed-thrombolysis for acute iliofemoral DVT. Median post-operative VDS and VS were 0 (P<0.001). 1pt developed an ulcer at 6mths.81pts had stenting for chronic outflow obstruction after failed medical management. 77pts (95%) had occluded vessels prior to treatment. The median pre-operative VS was 14 (4-23) and 9pts had an ulcer. Following intervention, the median VS was 4 (0-22, P<0.001) and ulcer healing was achieved in 67% (n=6/9).ConclusionsFirst-generation dedicated venous stents show promise at providing symptom relief in the short-term. Close surveillance is, however, required to maintain stent patency and factors that influence occlusion warrant further investigation. Long-term evaluation of these stents is required to investigate whether these encouraging early results can be maintained. DisclosuresSaha:Bayer: Honoraria. Black:Veniti: Consultancy. Cohen:Bayer: Consultancy, Honoraria, Research Funding, Speakers Bureau; Boehringer Ingelheim: Consultancy, Honoraria, Research Funding, Speakers Bureau; Daiichi Sankyo: Consultancy, Honoraria, Research Funding, Speakers Bureau; GSK: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding; Johnson and Johnson: Consultancy, Honoraria, Research Funding; Mitsubishi Pharma: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding. Karunanithy:Cook: Honoraria.

Oral direct thrombin inhibitors or oral factor Xa inhibitors for the treatment of deep vein thrombosis.

Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately 1 in 1,000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of novel oral anticoagulants (NOACs) have been developed: oral direct thrombin inhibitors (DTI) and oral factor Xa inhibitors. The new drugs have characteristics that may be favourable over conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or re-dosing and few known drug interactions. To date, no Cochrane review has measured the effectiveness and safety of these drugs in the treatment of DVT. To assess the effectiveness of oral DTIs and oral factor Xa inhibitors for the treatment of DVT. The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched January 2015) and the Cochrane Register of Studies (last searched January 2015). We searched clinical trials databases for details of ongoing or unpublished studies and the reference lists of relevant articles retrieved by electronic searches for additional citations. We included randomised controlled trials in which people with a DVT confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor for the treatment of DVT. Two review authors (LR, JM) independently extracted the data and assessed the risk of bias in the trials. Any disagreements were resolved by discussion with the third review author (PK). We performed meta-analyses when we considered heterogeneity low. The two primary outcomes were recurrent VTE and PE. Other outcomes included all-cause mortality and major bleeding. We calculated all outcomes using an odds ratio (OR) with a 95% confidence interval (CI). We included 11 randomised controlled trials of 27,945 participants. Three studies tested oral DTIs (two dabigatran and one ximelagatran), while eight tested oral factor Xa inhibitors (four rivaroxaban, two apixaban and two edoxaban). We deemed all included studies to be of high methodological quality and low risk of bias. The quality of the evidence was graded as high as the outcomes were direct and effect estimates were consistent and precise, as reflected in the narrow CIs around the ORs. Meta-analysis of three studies (7596 participants) comparing oral DTIs with standard anticoagulation groups showed no difference in the rate of recurrent VTE (OR 1.09; 95% CI 0.80 to 1.49), recurrent DVT (OR 1.08; 95% CI 0.74 to 1.58), fatal PE (OR 1.00; 95% CI 0.27 to 3.70), non-fatal PE (OR 1.12; 95% CI 0.66 to 1.90) or all-cause mortality (OR 0.82; 95% CI 0.60 to 1.13). However, oral DTIs were associated with reduced bleeding (OR 0.68; 95% CI 0.47 to 0.98). Meta-analysis of eight studies (16,356 participants) comparing oral factor Xa inhibitors with standard anticoagulation demonstrated a similar rate of recurrent VTE between the two treatments (OR 0.89; 95% CI 0.73 to 1.07). Oral factor Xa inhibitors were associated with a lower rate of recurrent DVT (OR 0.75; 95% CI 0.57 to 0.98). However, this was a weak association, heavily dependent on one study. The rate of fatal (OR 1.20; 95% CI 0.71 to 2.03), non-fatal PE (OR 0.94; 95% CI 0.68 to 1.28) and all-cause mortality (OR 0.90; 95% CI 0.65 to 1.23) was similar between the two treatment groups. Oral factor Xa inhibitors were also associated with reduced bleeding (OR 0.57; 95% CI 0.43 to 0.76). None of the included studies measured post-thrombotic syndrome or health-related quality of life. NOACs such as DTIs and factor Xa inhibitors may be an effective and safe alternative to conventional anticoagulation treatment for acute DVT.