A prospective,longitudinal study of central venous catheter‐related deep venous thrombosis in boys with hemophilia

Summary. Background: Central venous catheters (CVCs) are often inserted into boys with hemophilia to secure venous access for factor prophylaxis and immune tolerance induction therapy. Complications associated with CVCs include catheter‐related infections, local hemorrhage, and mechanical failure. Less frequently reported is CVC‐related deep venous thrombosis (DVT). We conducted a prospective study to determine the frequency and outcome of this complication. Methods: All boys (n = 16) with congenital hemophilia A or B with a CVC in place who were registered in the pediatric comprehensive care program at the Hospital for Sick Children, Toronto, were included in the study. They were prospectively assessed by imaging studies and clinical examinations for CVC‐related DVT at two time‐points, 2 years apart. Each boy was evaluated for inherited hypercoagulability. Results: Eleven (69%) of the 16 boys had radiological evidence of DVT at the first evaluation and 13/16 (81%) at the second evaluation. In two boys there was improvement in the venogram findings at the second evaluation. None of the CVC‐related DVTs completely resolved. Median age at the time of initial insertion of a CVC was 1.0 years (range 0.02–6.7 years). Median duration of CVC placement was 6.4 years (range 3.3–15.5 years). Only 4/13 boys with DVTs had clinical evidence of upper venous system obstruction. Only one boy, who did not develop a DVT, had a low protein C level. Conclusions: CVC‐related DVTs occur in the majority of boys with hemophilia who have CVCs inserted for a prolonged period of time. Annual screening with imaging is recommended for boys with CVCs in place for ≥ 3 years. Consideration should be given to removing CVCs as soon as peripheral venous access is feasible.     

肺癌合并静脉血栓栓塞症患者的危险因素及预后分析

目的探讨肺癌合并静脉血栓栓塞症(venous thromboembolism,VTE)发生的相关危险因素及VTE对预后生存的影响。方法回顾性收集2011年6月至2017年6月在中国医学科学院北京协和医学院肿瘤医院经细胞学或病理确诊为肺癌,接受系统性治疗的507例患者临床资料,分为VTE组(71例),非VTE组(436例)。单因素分析比较两组患者的临床特征、实验室检查结果,多因素logistic回归分析影响肺癌患者VTE发生的危险因素,Kaplan-Meier生存分析法绘制生存曲线。结果507例患者VTE发生率14.0%(71/507)。单因素分析示肺癌VTE组患者的Ⅲ~Ⅳ期、合并高血压病、心力衰竭、D-二聚体≥1.05mg/L、中心静脉置管(central venous catheter CVC)的比例显著高于非VTE组(P<0.05)。两组患者年龄、性别、卡氏体力状态评分(Karnofsky score,KPS)、体重指数(body mass index,BMI)、表皮生长因子(epidermal growth factor receptor,EGFR)基因突变、合并冠心病、糖尿病、心房颤动、化疗、放疗、白细胞计数、血小板计数、血红蛋白、甘油三酯、总胆固醇水平等变量比较,差异无显著性(P>0.05);多因素logistic回归分析显示:Ⅲ~Ⅳ期、合并高血压病、D-二聚体≥1.05mg/L、CVC是影响肺癌患者VTE发生的独立危险因素(P<0.05)。Kaplan-Meier生存分析法绘制生存曲线,VTE组患者中位生存时间42.0个月(95%CI:32.278~51.722),非VTE组为49.0个月(95%CI:44.234~53.766),差异有显著性(P=0.041)。结论临床分期Ⅲ~Ⅳ期、合并高血压病、D-二聚体≥1.05mg/L、CVC是肺癌患者VTE发生的独立危险因素,肺癌合并VTE的患者预后差,积极防治肺癌患者VTE相关危险因素,有助于降低VTE发生风险,改善患者预后。     

Predicting risk factors for thromboembolic complications in patients with sickle cell anaemia – lessons learned for prophylaxis

ObjectiveTo assess the clinical and laboratory predictors of venous thromboembolism (VTE) in patients with sickle cell anaemia (SCA) and its relationship to morbidity and mortality.MethodsThis retrospective case–control study analysed data from patients with SCA that experienced VTE compared with matched control patients with SCA but no VTE (2:1 ratio).ResultsA total of 102 patients with SCA were enrolled (68 cases with VTE and 34 controls). Amongst the 68 cases (median age, 29.5 years), 26 (38.2%) presented with isolated pulmonary embolism (PE). A higher prevalence of splenectomy (73.5% versus 35.3%) was observed in the cases compared with the controls. A significantly higher prevalence of central venous catheter (CVC) insertion (42.6% versus 8.8%) was observed in the cases compared with the controls. High white blood cell counts, serum lactic dehydrogenase (LDH), bilirubin and C-reactive protein (CRP) and low haemoglobin (Hb) and HbF were significant risk factors for VTE. Forty-two cases (61.8%) developed acute chest syndrome, 10 (14.7%) had a stroke and seven (10.3%) died.ConclusionsVTE in patients with SCA has a high impact on morbidity and mortality. PE was the leading presentation of VTE, with CVC insertion, high LDH, bilirubin, CRP and white blood cell counts along with low Hb and HbF constituting other significant risk factors.     

乳腺癌患者发生静脉血栓栓塞症危险因素分析

目的 探讨乳腺癌患者发生静脉血栓栓塞症的危险因素.方法 回顾性分析自2014年7月至2020年3月新汶矿业集团莱芜中心医院收治的90例女性乳腺癌患者临床资料,根据静脉血栓栓塞症发生情况分为未发生静脉血栓栓塞症的A组(n=60)与发生静脉血栓栓塞症的B组(n=30).记录两组患者的年龄、体质量指数、糖尿病病史、冠心病病史...     

The risk of venous thromboembolism associated with peripherally inserted central catheters in ambulant cancer patients

Background

Deep vein thrombosis (DVT) is a common complication of peripherally inserted central catheters (PICCs). PICCs are increasingly utilised in the management of cancer patients, a group which carries both additional risks for vascular thromboembolism as well as for complex morbidity. We analysed a cohort of cancer patients subjected to PICC insertion in a single cancer centre for the incidence of all-type vascular thromboembolism (VTE) and investigated relative risk factors.

Methods

In this clinical audit, the records of patients referred for PICC insertion in our centre in the period between 1/1/2011 and 1/4/2014 were retrospectively reviewed. The primary outcomes investigated were a) PICC-related deep vein thrombosis (PRDVT) and b) distant VTE (lower limb DVT and pulmonary embolism). 4Fr single lumen PICCs were placed in all patients. The Kaplan Meier method was used to study time from PICC insertion to PRDVT/VTE. Survival curves were compared using the log rank method. Logistic and Cox regression analyses were used to assess local, distant and combined endpoints.

Results

Four hundred ninety patients were included in the analysis of which 27 (5.5%) developed a PRDVT. Statistically significant risk factors for developing PRDVT in multivariate analysis included more than one attempt for insertion (OR 2.61, 95%CI: 1.12–6.05) and the use of fluoropyrimidine containing chemotherapy (OR 4.27, 95%CI 1.3–14.07). Twenty-six patients developed a distant VTE. Male gender was the only significant risk factor for distant VTE. When all-type VTE were considered together fluoropyrimidine containing chemotherapy (OR 4.54, 95% CI 1.63–12.61), male gender (OR 2.03, 95% CI 1.04–3.93) and white cell count (OR 1.12, 95% CI 1.00–1.26) were statistically significant as risk factors in this analysis.

Conclusions

This is a large study of VTE following PICC insertion in cancer patients which also looks at the rate of distant VTE. The observed PRDVT incidence is comparable with available literature. Fluoropyrimidine containing chemotherapy and more than one attempt for PICC insertion were independent predictors of PICC-associated VTE whilst the former remained an independent predictor of all-type VTE. Anticoagulation did not prevent thrombotic events in this cohort.

     

The role of aspirin in the prevention of thrombotic complications of thalidomide and anthracycline-based chemotherapy for multiple myeloma

OBJECTIVE: To study the efficacy of daily low-dose aspirin (81 mg orally) in decreasing the incidence of venous thromboembolic events (VTEs) in patients with multiple myeloma receiving pegylated doxorubicin, vincristine, and decreased-frequency dexamethasone, plus thalidomide (DVd-T). PATIENTS AND METHODS: In this phase 2 clinical trial of DVd-T, conducted by the Cleveland Clinic Foundation from August 2001 to October 2003, 105 patients were enrolled. The first 35 patients experienced increased numbers of VTEs. von Willebrand levels and platelet aggregation to ristocetin before and after treatment with DVd-T increased significantly, suggesting a pathophysiology involving platelet-endothelial interaction. Aspirin was added to the regimen, thus generating 3 patient groups: group 1 received aspirin from the start of DVd-T treatment before the study began (58 patients), group 2 received aspirin after the start of DVd-T treatment and after the study began (26 patients), and group 3 did not receive daily low-dose aspirin during the study (19 patients). Two patients being treated with warfarin for other indications were excluded from the study. The primary end point for this study was the incidence of VTE in the form of either deep venous thrombosis or pulmonary embolism. Secondary end points were the time to the first VTE, time to the composite end point of death or first VTE, and incidence of bleeding complications. RESULTS: After a median follow-up of 24 months, on an intent-to-treat basis, 26 posttreatment VTEs occurred after a median of 90 days, with 19% occurring in group 1, 15% in group 2, and 58% in group 3. Following multivariate time-to-event analysis, aspirin use continued to be associated with lower relative risk of VTE (hazard ratio, 0.22; confidence interval, 0.10-0.47; P<.001) and of the composite end point (hazard ratio, 0.28; confidence interval, 0.15-0.51; P<.001). CONCLUSION: Daily low-dose aspirin (81 mg orally) given to patients with newly diagnosed and relapsed/refractory multiple myeloma who were receiving DVd-T reduced the incidence of VTEs without an increase in bleeding complications.     

Venous thromboembolic disease: an observational study in medical-surgical intensive care unit patients

Purpose: Acute and chronic illness, immobility, and procedural and pharmacologic interventions may predispose patients in the intensive care unit (ICU) to venous thromboembolic (VTE) disease. The purpose of this study was to observe potential risk factors and diagnostic tests for VTE, and prophylaxis against VTE in medical-surgical ICU patients. Materials and Methods: In a prospective observational study, 93 consecutive patients admitted to a mixed medical-surgical ICU were followed. We recorded demographics, admitting diagnoses, APACHE II score, VTE risk factors, antithrombotic, anticoagulant and thrombolytic agents, diagnostic tests for deep venous thrombosis (DVT) and pulmonary embolus (PE), and clinical outcomes. Results: Patients were 65.5 (15.5) years old with an APACHE II score of 21.1 (9.0); 44 (47.3%) were female. Admission diagnoses were medical (58, 67.4%) and surgical (35, 37.6%). The duration of ICU stay was 3 days (interquartile range: 1, 8.5 days) and the ICU mortality rate was 20.4% (19 of 93). We observed 8 VTE events among 5 of 93 patients (incidence 5.4% [0.8 to 10.0]); 2 patients had DVT and PE before admission, 1 had DVT as an admitting diagnosis, 1 had DVT on day 2 and PE on day 3, and 1 had PE on day 2. Over 804 ICU patient-days, 2 of 5 ultrasound examinations diagnosed DVT and 2 of 3 ventilation-perfusion lung scans diagnosed PE. Of 64 patients in whom heparin was not contraindicated and who were not anticoagulated, subcutaneous heparin prophylaxis was prescribed for 40 (62.5%) patients. ICU-acquired VTE risk factors were mechanical ventilation (odds ratio [OR] 1.56), immobility (OR 2.14), femoral venous catheter (OR 2.24), sedatives (OR 1.52), and paralytic drugs (OR 4.81), whereas VTE heparin prophylaxis (OR 0.08), aspirin (OR 0.42), and thromboembolic disease stockings (OR 0.63) were associated with a lower risk. Only warfarin (OR 0.07, P = .01) and intravenous heparin (OR 0.04, P < .01) were associated with a significantly decreased risk of VTE. Conclusions: Several ICU-acquired risk factors for VTE were documented in this medical-surgical ICU. VTE prophylaxis was underprescribed, and VTE diagnostic tests were infrequent. Further research is required to determine the incidence, predisposing factors, attributable morbidity, mortality, and costs of VTE in medical-surgical ICU patients, the optimal diagnostic test strategies, and the most cost-effective approaches of prophylaxis. Copyright © 2000 by W.B. Saunders Company     

The metabolic syndrome and the risk of venous thrombosis: a case–control study

OBJECTIVE: The results of recent studies have suggested that patients with idiopathic venous thromboembolism (VTE) might be at increased risk of asymptomatic atherosclerosis and cardiovascular events. The metabolic syndrome is a cluster of risk factors for atherosclerosis. Its impact on VTE is unknown. METHODS: In a case-control study, consecutive patients with objectively confirmed deep vein thrombosis (DVT) and control subjects with objectively excluded DVT underwent clinical assessment for the presence of the metabolic syndrome according to the National Cholesterol Education Program criteria. The presence of known risk factors for DVT was documented. Patients with DVT secondary to cancer were excluded. The prevalence of the metabolic syndrome was compared between patients with idiopathic DVT and controls. RESULTS: We enrolled 93 patients with a first episode of idiopathic DVT and 107 controls. The mean age was 65.1 and 63.7 years, respectively. The metabolic syndrome was diagnosed in 50.5% of patients with idiopathic DVT and in 34.6% of controls [odds ratio (OR) 1.93; 95% confidence interval (CI) 1.05, 3.56]. After adjustment for age, sex, body mass index, and smoke, the metabolic syndrome remained independently associated with idiopathic DVT (OR 1.94; 95% CI 1.04, 3.63). In patients with secondary DVT, the prevalence of the metabolic syndrome was 27%. CONCLUSIONS: The metabolic syndrome may play a role in the pathogenesis of idiopathic DVT and may act as link between venous thrombosis and atherosclerosis.     

Burden of illness in venous thromboembolism in critical care: a multicenter observational study

PURPOSE: The frequency of clinically diagnosed venous thromboembolism (VTE) including deep venous thrombosis (DVT) and pulmonary embolism (PE) in medical-surgical critically ill patients is unclear. The objectives of this study were to estimate the prevalence and incidence of radiologically confirmed DVT and PE in medical-surgical intensive care unit (ICU) patients and to determine the impact of prophylaxis on the frequency of these events. MATERIALS AND METHODS: In a retrospective observational cohort study in 12 adult ICUs, we identified prevalent cases (diagnosed in the 24 hours preceding ICU admission up to 48 hours post-ICU admission) and incident cases (diagnosed 48 hours or more after ICU admission and up to 8 weeks after ICU discharge) of upper or lower limb DVT or PE. Deep venous thrombosis was diagnosed by compression ultrasound or venogram. Each DVT was classified as clinically suspected or not clinically suspected in that the latter was diagnosed by scheduled screening ultrasonography. Pulmonary embolism was diagnosed by ventilation-perfusion lung scan, computed tomography pulmonary angiography, echocardiography, electrocardiography, or autopsy. RESULTS: Among 12,338 patients, 252 (2.0%) patients had radiologically confirmed DVT or PE and another 47 (0.4%) had possible DVT or PE. Prevalent DVTs were diagnosed in 0.4% (95% confidence interval [CI], 0.3%-0.5%) of patients and prevalent PEs were diagnosed in 0.4% (95% CI, 0.3%-0.6%). Incident DVTs were diagnosed in 1.0% (95% CI, 0.8%-1.2%) of patients, and incident PEs were diagnosed in 0.5% (95% CI, 0.4%-0.6%). Of patients with incident VTE, 65.8% of cases occurred despite receipt of thromboprophylaxis for at least 80% of their days in ICU. The median (interquartile range) ICU length of stay was similar for patients with DVT (7 [3-17]) and PE (5 [2-8]). For all patients with VTE, ICU mortality was 16.7% (95% CI, 12.0%-21.3%) and hospital mortality was 28.5% (95% CI, 22.8%-34.1%). CONCLUSIONS: Venous thromboembolism appears to be an apparently infrequent, but likely underdiagnosed problem, occurring among patients receiving prophylaxis. Findings suggest the need for increased suspicion among clinicians, renewed efforts at thromboprophylaxis, and evaluation of superior prevention strategies.     

Superficial vein thrombosis and recurrent venous thromboembolism: a pooled analysis of two observational studies

Summary. Background: The management strategies for symptomatic isolated superficial vein thrombosis (SVT) (without concomitant deep vein thrombosis [DVT] or pulmonary embolism [PE]) have yet to achieve widespread consensus. Concerns have been raised regarding the usefulness of prescribing anticoagulant treatments to all patients with isolated SVT. Determining the isolated SVT subgroups who have the highest risks of venous thromboembolism (VTE) recurrence (composite of DVT, PE, and new SVT) may facilitate the identification of patients who are likely to benefit from anticoagulant treatment. Design and methods: We performed a pooled analysis on individual data from two observational, multicenter, prospective studies, to determine predictors for VTE recurrence and their impact in an unselected population of symptomatic isolated SVT patients. Results: One thousand and seventy‐four cases of symptomatic isolated SVT were followed up at 3 months. VTE recurrence was observed in 3.9% of the patients; 16.2% of the patients did not receive anticoagulants, and 0.6% experienced a VTE recurrence. Cancer, personal history of VTE and saphenofemoral/popliteal involvement significantly increased the risk of subsequent VTE or DVT/PE in univariate analyses. Only male sex significantly increased the risk of VTE or DVT/PE recurrence in multivariate analyses. Twelve per cent of the patients had cancer or saphenofemoral junction involvement, and were at higher risk of DVT/PE recurrence than patients without those characteristics (4.7% vs. 1.9%, P = 0.06). Conclusions: In patients with symptomatic SVT, only male sex significantly and independently increased the risk of VTE recurrence. Cancer or saphenofemoral junction involvement defined a population at high risk for deep VTE recurrence. Some SVTs might be safely managed without anticoagulants.     

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

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.     

Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis

See also Watson HG. RVO – Real value obscure. This issue, pp 1116–8; Le Gal G, Carrier M, Kovacs MJ, Betancourt MT, Kahn SR, Wells PS, Anderson DA, Chagnon I, Solymoss S, Crowther M, Righini M, Delluc A, White RH, Vickars L, Rodger M. Residual vein obstruction as a predictor for recurrent thromboembolic events after a first unprovoked episode: data from the REVERSE cohort study. This issue, pp 1126–32. Summary. Background: Residual vein obstruction (RVO) detected on compression ultrasonography of the leg after a few months of anticoagulation therapy might be able to identify patients with deep vein thrombosis (DVT) at high risk of having a recurrent venous thromboembolism (VTE). Aim: To determine whether RVO is associated with an increased risk of recurrent events in patients with DVT. Patients and Methods: A systematic literature search strategy was conducted using MEDLINE, EMBASE, and the Cochrane Register of Controlled Trials. We selected 14 articles (nine prospective cohort studies and five randomized controlled trials) that included patients with DVT who had an assessment for RVO with the use of compression ultrasonography. Two reviewers independently extracted data onto standardized forms. Results: Overall, the presence of RVO was not associated with an increased risk of recurrent VTE (odds ratio [OR] 1.24, 95% confidence interval [CI] 0.9–1.7) in patients with unprovoked DVT who stopped oral anticoagulation therapy at the time of RVO assessment. However, RVO was significantly associated with recurrent VTE in patients with any (unprovoked or provoked) DVT (OR 1.5, 95% CI 1.1–2.0). Conclusions: RVO was associated with a modestly increased risk of recurrent VTE in patients with DVT (unprovoked and provoked). However, RVO did not seem to be a predictor of recurrent VTE in patients with unprovoked DVT following anticoagulation discontinuation. Further prospective studies are needed to assess the role of RVO in patients with unprovoked DVT.     

Comparison of the clinical history of symptomatic isolated distal deep‐vein thrombosis vs. proximal deep vein thrombosis in 11 086 patients

Background: The clinical significance of symptomatic isolated distal deep vein thrombosis (DVT) is uncertain. Consequently, this leads to important disparities in its management. Objective: To examine the clinical history of isolated distal DVT and to compare it with that of proximal DVT. Methods: Using data from the international, prospective, RIETE registry on patients with confirmed symptomatic venous thromboembolism (VTE), we compared the risk factors and 3‐month outcome in patients with isolated distal DVT vs. proximal DVT. Results: Eleven thousand and eighty‐six patients with symptomatic DVT, but without pulmonary embolism, were included between 2001 and 2008; 1921 (17.3%) exhibited isolated distal DVT. Anticoagulant treatment was received by 89.1% (1680/1885) of isolated distal DVT and 91.8% (7911/8613) of proximal DVT patients for the entire follow‐up period. Isolated distal DVTs were more associated with transient risk factors (i.e. recent travel, hospitalization, recent surgery), whereas proximal DVTs were more associated with chronic states (i.e. ≥75 years or with active cancer). At 3 months, major bleeding rate was lower in patients with isolated distal DVT (1.0% vs. 2.2%, P < 0.01), whereas VTE recurrence rate was equivalent (2.0% vs. 2.7%, P = 0.07). The mortality rate was lower in patients with isolated distal DVT (2.7% vs. 7.5%; P < 0.001); this was mainly due to a lower rate of non‐VTE‐related deaths (2.2% vs. 6.3%; P < 0.001). Active cancer was the main predictive factor of death in patients with isolated distal DVT. Conclusions: Proximal and isolated distal DVT patients differ in terms of risk factors and clinical outcomes, suggesting different populations. In the short term, the life expectancy of patients with isolated distal DVT depended chiefly on their cancer status.     

Incidence, risk profile and morphological pattern of venous thromboembolism after prostate cancer surgery

Summary.  Background : Venous thromboembolism (VTE) is the most common non-surgical complication after major pelvic surgery. Little is known about the risk factors or the time of development of postoperative venous thrombosis. Methods: A cohort of 523 consecutive patients undergoing radical prostatectomy with lymphadenectomy was prospectively assessed by complete compression ultrasound at days −1, +8 and +21. Results: Complete data were available in 415 patients, while four patients had VTE before surgery and were excluded from the analysis. In the remaining 411 patients, 71 VTE events were found in 69 patients (16.8%). Most were limited to calf muscle veins (56.5%), followed by deep calf vein thrombosis (23.2%), proximal deep vein thrombosis (DVT, 14.5%) and pulmonary embolism (PE, 5.8%). Of the 14 patients with proximal DVT/PE, 11 patients (78.6%) developed VTE between days 8 and 21. Risk factors for VTE were a personal history of VTE (OR 3.0), pelvic lymphoceles (LCs) impairing venous flow (OR 2.8) and necessity of more than two units of red blood cells (OR 2.6). Conclusion: Venous thromboembolism is common after radical prostatectomy. A significant proportion develops after day 8, suggesting that prolonged heparin prophylaxis should be considered. Since LCs with venous flow reduction result in higher rates of VTE, hemodynamically relevant lymphoceles should be surgically treated.     

Venous thromboembolic prophylaxis: the use of aspirin

Venous thromboembolism (VTE) is a term used collectively for deep vein thrombosis (DVT) and pulmonary embolism. Without prophylaxis, the incidence of documented DVT in the orthopaedic surgery patient is reported in the range of 50%-60%. A multimodal approach to DVT prophylaxis is the standard of care for all patients undergoing total hip arthroplasty and total knee arthroplasty. At our local hospital, low-risk patients are being sent home with aspirin as the medication for VTE prophylaxis. This article will provide an overview of the pathophysiology of VTE and the current prevention guidelines including the use of aspirin.     

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

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.     

A randomized study comparing the efficacy and safety of nadroparin 2850 IU (0.3 mL) vs. enoxaparin 4000 IU (40 mg) in the prevention of venous thromboembolism after colorectal surgery for cancer

BACKGROUND: The optimal thromboprophylactic dosage regimen of low-molecular-weight heparins in high-risk general surgery remains debatable. OBJECTIVES: We performed a randomized, double-blind study to compare the efficacy and safety of nadroparin 2850 IU (0.3 mL) and enoxaparin 4000 IU (40 mg) in the prevention of venous thromboembolism (VTE) after colorectal surgery for cancer. Patients and methods: Patients undergoing resection of colorectal adenocarcinoma were randomized to receive once daily either 2850 IU nadroparin or 4000 IU enoxaparin s.c. for 9 +/- 2 days. The primary efficacy outcome was the composite of deep vein thrombosis (DVT) detected by bilateral venography or documented symptomatic DVT or pulmonary embolism up to day 12. The main safety outcome was major bleeding. A blinded independent committee adjudicated all outcomes. RESULTS: Out of 1288 patients analyzed, efficacy was evaluable in 950 (73.8%) patients. The VTE rate was 15.9% (74/464) in nadroparin-treated patients and 12.6% (61/486) in enoxaparin-treated patients, a relative risk of 1.27 (95% confidence interval; CI: 0.93-1.74) that did not met the criterion for non-inferiority of nadroparin. The rate of proximal DVT was comparable in the two groups (3.2% vs. 2.9%, respectively), but that of symptomatic VTE was lower in nadroparin-treated patients (0.2% vs. 1.4%). There was significantly (P = 0.012) less major bleeding in nadroparin- than in enoxaparin-treated patients (7.3% vs. 11.5%, respectively). CONCLUSION: Compared with those receiving enoxaparin 4000 IU, patients treated with nadroparin 2850 IU showed a higher incidence of asymptomatic distal DVT, but a lower incidence of symptomatic VTE. Nadroparin treatment was safer in terms of bleeding risk.     

Combined computed tomography venography and pulmonary angiography for the diagnosis PE and DVT in the ED

The purpose of this study is to evaluate the usefulness of combined computed tomography venography and pulmonary angiography (CTVPA) in the diagnosis of venous thromboembolic (VTE) disease in the emergency department (ED). CTVPA images and clinical data of 73 nonselected patients with suspected pulmonary embolism (PE) and/or deep venous thrombosis (DVT) were retrospectively assessed. CTVPA correctly identified 33 of 34 patients with VTE disease, including 7 patients with PE alone, 11 patients with DVT alone, and 16 patients with both PE and DVT. Among the 27 patients with DVT, CTVPA disclosed thrombosis involving the abdominal and pelvic veins in 4 patients, and isolating to the inferior vena cava and iliac vein in one patient. CTVPA showed high accuracy in the diagnosis of both PE and DVT, in comparison with lower extremity venous sonography and ventilation-perfusion scintigraphy. In 26 (66%) of the 39 patients without of evidence VTE, CTVPA provided important ancillary information that suggests additional or alternative diagnoses. CTVPA is therefore an appropriate single diagnostic tool for evaluation VTE disease in the ED.     

The association of active cancer with venous thromboembolism location: a population-based study

OBJECTIVE: To test active cancer for an association with venous thromboembolism (VTE) location.PATIENTS AND METHODS: Using the resources of the Rochester Epidemiology Project, we identified all Olmsted County, MN, residents with incident VTE during the 35-year period 1966-2000 (N=3385). We restricted analyses to residents with objectively diagnosed VTE during the 17-year period from January 1, 1984, to December 31, 2000 (N=1599). For each patient, we reviewed the complete medical records in the community for patient age, gender, and most recent body mass index at VTE onset; VTE event type and location; and previously identified independent VTE risk factors (ie, surgery, hospitalization for acute medical illness, active cancer, leg paresis, superficial venous thrombosis, and varicose veins). Using logistic regression we tested active cancer for an association with each of 4 symptomatic VTE locations (arm or intra-abdominal deep venous thrombosis [DVT], intra-abdominal DVT, pulmonary embolism, and bilateral leg DVT), adjusted for age, gender, body mass index, and other VTE risk factors.RESULTS: In multivariate analyses, active cancer was independently associated with arm or intra-abdominal DVT (odds ratio [OR], 1.76; P=.01), intra-abdominal DVT (OR, 2.22; P=.004), and bilateral leg DVT (OR, 2.09; P=.02), but not pulmonary embolism (OR, 0.93).CONCLUSION: Active cancer is associated with VTE location. Location of VTE may be useful in decision making regarding cancer screening.BMI = body mass index; CI = confidence interval; CTEPH = chronic thromboembolic pulmonary hypertension; DVT = deep venous thrombosis; OR = odds ratio; PE = pulmonary embolism; VTE = venous thromboembolismThe association between cancer and venous thromboembolism (VTE) is well-established and strong.^1-4 Active cancer with and without chemotherapy increases VTE risk by 5- to 6-fold.⁵ Furthermore, active cancer accounts for about 20% of the entire VTE burden occurring in a community.⁶ Indeed, VTE is the second most common cause of death among patients with cancer.⁷ Cancer patients with VTE have a 2-fold or greater increase in mortality compared with cancer patients without VTE, even after adjusting for stage.^8,9 Nearly half of the patients with cancer-associated VTE have distant metastases at the time of VTE diagnosis.⁸ The incidence of cancer in patients with recurrent idiopathic VTE is higher than that in patients with secondary VTE.³Opinions differ regarding screening for an underlying occult cancer after an idiopathic VTE event.^10,11 Although a small randomized clinical trial found that more occult cancers were detected at an early stage with extensive screening, which theoretically could improve cancer treatment potential, no difference in survival was noted between this strategy and usual care.¹⁰ Because anticoagulant therapy improves the outcomes of patients with VTE and cancer, it is still important to recognize which patients with VTE have an underlying active cancer.¹² The diagnosis of VTE may help to uncover previously occult cancer by prompting a complete physical examination and testing consistent with standard health care maintenance. However, indiscriminate cancer screening is not cost-effective.^13,14 To provide a more organized and cost-effective approach to cancer detection among patients with VTE, the VTE characteristics associated with cancer must be recognized. Although evidence shows that idiopathic VTE and bilateral deep venous thrombosis (DVT) correlate with subsequent cancer diagnosis,^3,15 there is a paucity of data regarding the association between active cancer and VTE location. The current study aims to determine whether underlying cancer is associated with particular VTE locations.     

Residual vein obstruction as a predictor for recurrent thromboembolic events after a first unprovoked episode: data from the REVERSE cohort study

See also Watson HG. RVO – Real value obscure. This issue, pp 1116–8; Carrier M, Rodger MA, Wells PS, Righini M, Le Gal G. Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis. This issue, pp 1119–25. Summary. Objectives: There is growing interest in using residual vein obstruction (RVO) to guide the duration of oral anticoagulant therapy (OAT) for unprovoked deep vein thrombosis (DVT). We sought to determine if RVO as determined by compression ultrasonography (CUS) after completion of 5–7 months of anticoagulation for unprovoked DVT is associated with an increased risk of recurrent venous thromboembolism (VTE). Materials and Methods: This was a multicentre multinational prospective cohort study undertaken in tertiary care centers. Patients with a first ‘unprovoked’ major VTE were enrolled over a 4‐year period and completed a mean 18‐month follow‐up in September 2006. All 452 patients with DVT had baseline CUS at inclusion to assess any RVO before stopping OAT at 5–7 months. During follow‐up off OAT, all episodes of suspected recurrent VTE were independently adjudicated with reference to baseline imaging. Results: Forty‐five out of 231 patients with abnormal CUS (19.5%) had recurrent VTE during follow‐up, as compared with 32 out of 220 patients with normal CUS (14.6%), and one patient had inadequate CUS. There was no significant association between an abnormal CUS at inclusion and the risk of recurrent VTE: hazard ratio 1.4 (95% confidence interval, 0.9–2.1), P = 0.19. None of the different degrees of clot resolution on baseline CUS was statistically significantly associated with the risk of recurrent VTE. Conclusion: In our study, the presence of RVO at the time of OAT withdrawal was not associated with a statistically significant higher risk of recurrent VTE. RVO assessment may not be useful to guide duration of anticoagulation.