多排CT对肺动脉栓塞和下肢深静脉血栓检出的研究

目的:评价运用CT肺动脉造影和下肢CT静脉造影(CTVPA)两种方法对肺动脉栓塞(PE)和下肢深静脉血栓(DVT)检出的应用价值。方法:对38例临床怀疑PE的患者行CTVPA检查,分析其影像表现,并探讨其应用价值。结果:38例患者中PE24例,下肢DVT11例。PE主要表现为血管腔内充盈缺损和同侧肺野内病变。下肢DVT主要表现为下肢深静脉管腔内充盈缺损、静脉增粗和患肢软组织肿胀。对于栓子的显示,多层面容积重建(MPVR)优于最大密度投影(MIP)和容积再现(VR)。结论:多排CT(MSCT)联合运用CT肺动脉造影和CTVPA两种方法对PE和下肢DVT检出有很大的应用价值,可作为临床怀疑PE的患者首选检查方法。     

Preventing and Recognizing Venous Thromboembolism After Obstetric and Gynecologic Surgery

Venous thromboembolism (VTE) is a hypercoagulable disorder that is associated with two potential significant complications—deep venous thrombosis (DVT) and pulmonary embolus (PE). During pregnancy and the postpartum period, the risk for VTE is increased. Prevention is optimal, but early detection and treatment of VTE in women after obstetric and gynecologic surgery is imperative, as DVT is often asymptomatic and, in many patients, clinical presentation only occurs after a fatal PE occurs.     

Rivaroxaban for the Treatment of Pulmonary Embolism

With the advent of new oral anticoagulants (NOACs) for the treatment of deep-vein thrombosis (DVT) and/or pulmonary embolism (PE), a new era of oral anticoagulation for patients with venous thromboembolism (VTE) has begun. Rivaroxaban is the first NOAC to receive regulatory approval for the acute and continued treatment of DVT and PE, and for the secondary prevention of VTE. Here, the clinical trials of rivaroxaban in patients with VTE are reviewed, and the clinical use of rivaroxaban for patients with PE is discussed. Even though rivaroxaban will facilitate the therapeutic management of PE, its use in specific clinical situations needs further study.     

血栓弹力图在下肢深静脉血栓与肺栓塞的应用价值

[目的]探讨血栓弹力图对下肢深静脉血栓形成(DVT)患者与DVT合并肺栓塞(PE)患者的应用价值.[方法]选择2014年3~9月本院收治的新发DVT及DVT合并PE患者12例,其中新发DVT患者8例,DVT合并PE患者4例,选择同期无DVT或PE病史的12例健康体检者为对照组,均行下肢静脉彩超、肺动脉CT血管成像(CTA)、血栓弹力图等检查.比较DVT患者及DVT合并PE患者在血栓弹力图相关指标如凝血反应时间(R值)、凝固时间(K值)、最大血凝块强度(MA)、凝固角(Angel)、凝血综合指数(CL)的异同点.[结果]DVT组、DVT合并PE组与对照组在年龄、性别、R、MA、K、Angel、CL方面比较,组间比较差异无统计学意义(P>0.05).[结论]下肢深静脉血栓形成与下肢深静脉血栓形成合并肺栓塞在血栓弹力图指标上无明显差异,血栓弹力图在VTE中的应用价值尚需进一步研究.     

Venous thromboembolism in the ICU: main characteristics,diagnosis and thromboprophylaxis

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep venous thrombosis (DVT), is a common and severe complication of critical illness. Although well documented in the general population, the prevalence of PE is less known in the ICU, where it is more difficult to diagnose and to treat. Critically ill patients are at high risk of VTE because they combine both general risk factors together with specific ICU risk factors of VTE, like sedation, immobilization, vasopressors or central venous catheter. Compression ultrasonography and computed tomography (CT) scan are the primary tools to diagnose DVT and PE, respectively, in the ICU. CT scan, as well as transesophageal echography, are good for evaluating the severity of PE. Thromboprophylaxis is needed in all ICU patients, mainly with low molecular weight heparin, such as fragmine, which can be used even in cases of non-severe renal failure. Mechanical thromboprophylaxis has to be used if anticoagulation is not possible. Nevertheless, VTE can occur despite well-conducted thromboprophylaxis.     

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

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.     

Tandem measurement of D-dimer and myeloperoxidase or C-reactive protein to effectively screen for pulmonary embolism in the emergency department

OBJECTIVES: The hypothesis was that the tandem measurement of D-dimer and myeloperoxidase (MPO) or C-reactive protein (CRP) could significantly decrease unnecessary pulmonary vascular imaging in emergency department (ED) patients evaluated for pulmonary embolism (PE) compared to D-dimer alone. METHODS: The authors measured the sequential combinations of D-dimer and MPO and D-dimer and CRP in a prospective sample of ED patients evaluated for PE at two centers. Patients were followed for 90 days for venous thromboembolism (VTE, either PE or deep venous thrombosis [DVT]), which required the consensus of two of three blinded physician reviewers. RESULTS: The authors enrolled 304 patients, 22 with VTE (7%; 95% confidence interval [CI] = 5% to 10%). The sensitivity and specificity of a D-dimer alone (cutoff > or = 500 ng/mL) were 100% (95% CI = 85% to 100%) and 59% (95% CI = 53% to 65%), respectively, and was followed by pulmonary vascular imaging negative for PE in 38% (115/304; 95% CI = 32% to 44%). The combination of either a negative D-dimer, or MPO < 22 mg/dL, had a sensitivity of 100% and specificity of 73% (95% CI = 67% to 78%). Thus, tandem measurement of D-dimer and MPO would have decreased the frequency of subsequent negative pulmonary vascular imaging from 38% to 25% (95% CI of the difference of -13% = -5% to -20%). The combination of CRP and D-dimer would not have significantly improved the rate of negative imaging. CONCLUSIONS: The tandem measurement of D-dimer and MPO would have significantly decreased negative pulmonary vascular imaging compared with D-dimer alone and should be validated prospectively.     

D-dimer levels in VTE patients with distal and proximal clots

Objectives

There is growing evidence that venous thromboembolism (VTE) patients with distal clots (distal calf deep vein thrombosis [DVT] and sub-segmental pulmonary embolism [PE]) may not routinely benefit from anticoagulation. We compared the D-dimer levels in VTE patients with distal and proximal clots.

Contribution of indirect computed tomography venography to computed tomography angiography of the chest for the diagnosis of thromboembolic disease in two United States emergency departments

Summary.  Recent reports suggest that physicians in non-ambulatory settings can use indirect CT venography (CTV) of the lower extremities immediately following spiral CT angiography (CTA) of the chest to identify patients with a negative CTA who have thromboembolic disease identified on CTV. We sought to determine the frequency of isolated deep venous thrombosis (DVT) discovered on CTV in emergency department (ED) patients with complaints suggestive of pulmonary embolism (PE) yet having a negative CTA. This study was conducted in a suburban and urban ED where patients with symptoms suspicious for PE were primarily evaluated with CTA and CTV. A total of 800 patients were studied, including 360 from the suburban ED and 440 from the urban ED. 88 (11%) patients were diagnosed with thromboembolic disease by CTA, or CTV, or both. Seventy-three patients had a CTA of the chest that was positive for PE, 42 (5.2%) of whom had evidence of both PE on CTA and DVT on CTV. Fifteen patients (2%, 95% CI = 1–3%) had a negative CTA and were subsequently found to have isolated DVT on CTV, all of whom received anticoagulation therapy. These data suggest that indirect CT venography of immediately following CT angiography of the chest significantly increased the frequency of diagnosed thromboembolic disease requiring anticoagulation in ED patients with suspected PE.     

Guidelines and the use of inferior vena cava filters: a review of an institutional experience

Summary.  Background and objectives:  Based on the American College of Chest Physicians 2004 antithrombotic therapy for venous thromboembolism (VTE) and the Eastern Association for the Surgery of Trauma 2002 guidelines, placement of an inferior vena cava (IVC) filter is indicated in patients who either have, or are at high risk for, VTE, but have a contraindication or failure of anticoagulation. Our aim is to compare clinical characteristics and outcomes of patients receiving IVC filters within-guidelines (WG) and outside-of-guidelines (OOG). Methods:  The 558 patients who received an IVC filter were divided into two groups called WG or OOG. The WG group met the criteria described above and the OOG group did not have a contraindication to or a failure of anticoagulation. Results:  The WG group had 362 patients and the OOG group had 196 patients. The OOG group had one (0.5%) patient with post-filter pulmonary embolism (PE), two (1%) with IVC thrombosis, and seven (3.6%) with deep vein thrombosis (DVT). The WG group had five (1.4%) patients with post-filter PE, 13 (3.6%) with IVC thrombosis, and 34 (9.4%) with DVT. All patients who developed post-filter PE had a DVT before filter placement, and patients who did not have a prior VTE event were at a significantly lower risk of developing post-filter IVC thrombosis and PE. Conclusion:  Our data do not support the use of an IVC filter outside of guidelines in patients without prior VTE who can tolerate anticoagulation because of the low risk of developing PE.     

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.     

Prevention and diagnosis of venous thromboembolism in critically ill patients: a Canadian survey

Background  

Venous thromboembolism (VTE) confers considerable morbidity and mortality in hospitalized patients, although few studies have focused on the critically ill population. The objective of this study was to understand current approaches to the prevention and diagnosis of deep venous thrombosis (DVT) and pulmonary embolism (PE) among patients in the intensive care unit (ICU).     

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 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     

脊柱外科手术后静脉血栓栓塞症自然发生率的临床研究

目的 分析脊柱手术后静脉血栓栓塞症（VTE）的自然发生率,探讨采取干预措施抗凝以预防VTE的必要性;结合文献,分析VTE的发生与手术方式、体位、时间等关系,指导临床改进相关环节.方法 2011年1月至2012年1月收治的接受脊柱手术患者168例,术前进行血常规、凝血指标及双下肢静脉彩超检查.术后复查双下肢静脉彩超.随访时间3个月.如果彩超怀疑深静脉血栓（DVT）,行下肢静脉造影确诊;如果高度怀疑肺栓塞（PE）形成,行肺血管造影确诊.统计患者资料及VTE例数.通过SPSS 11.0软件,利用x2检验、Mann-Whitney检验分析.结果 168例患者中确诊VTE1例,无PE病例.脊柱手术后VTE自然发生率为0.60％.尝试分析VTE阳性组与阴性组在性别、年龄、体重、手术时间、部位、入路、失血量、卧床时间等方面是否存在统计学差异.但由于VTE阳性例数少,随机性大,未能进行分析.结论 本次研究结果与文献报道类似,显示脊柱手术围手术期不采用抗凝措施下,VTE自然发生率较低;脊柱手术后对于无VTE症状以及不存在VTE危险因素的患者不需要行双下肢静脉彩超检查、血管造影检查以及常规抗凝处理.     

Statin use and the prevention of venous thromboembolism: a meta‐analysis

Aims: Statins are thought to have antithrombotic properties and may attenuate patients’ odds of developing venous thromboembolism (VTE), but clinical studies have yielded variable estimates of this effect. The aim was to conduct a meta‐analysis to evaluate the effect of statin use on development of VTE. Methods: Randomised controlled trials (RCTs) and observational studies evaluating the effects of statins on the incidence of VTE were selected from MEDLINE (1996 to August 2009), Cochrane CENTRAL (second quarter, 2009), Cochrane Database of Systematic Reviews (second quarter, 2009) and a manual review of references. While no further restrictions were placed on RCTs, observational studies were only included if they reported adjusted effect sizes using appropriate methods. Development of deep vein thrombosis (DVT), pulmonary embolism (PE) and any VTE from RCTs and observational studies were pooled using traditional meta analytic techniques with a random‐effects model. Results: Ten studies were identified and eligible for meta‐analysis. Upon meta‐analysis, statin use was associated with a statistically significant reduction in the odds of developing VTE (AOR 0.68, 95% CI 0.54–0.86), DVT (AOR 0.59, 95% CI 0.43–0.82) and PE (AOR 0.70, 95% CI 0.53–0.94). Discussion: Statin use is associated with significantly reduced odds of developing VTE, DVT or PE by 32%, 41% and 30% respectively. Our meta‐analysis included one RCT, JUPITER, which alone provided statistically significant reduction in the odds of developing VTE and DVT (43% and 55% respectively), and a nonsignificant reduction on PE. Conclusion: Currently available evidence suggests that statins can reduce patients’ odds of developing VTE.     

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.     

Does the clinical presentation and extent of venous thrombosis predict likelihood and type of recurrence? A patient‐level meta‐analysis

Summary. Aim: To determine if the mode of presentation of venous thromboembolism (VTE), as deep vein thrombosis (DVT) or pulmonary embolism (PE), predicts the likelihood and type of recurrence. Methods: We carried out a patient‐level meta‐analysis of seven prospective studies in patients with a first VTE who were followed after anticoagulation was stopped. We used Kaplan‐Meier analysis to determine the cumulative incidence of recurrent VTE according to mode of presentation, and multivariable Cox regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for mode of and extent of DVT as potential risk factors for recurrence. Results: The 5‐year cumulative rate of recurrent VTE in 2554 patients was 22.6%. In 869 (36.1%) patients with PE, the 5‐year rate of any recurrence (DVT or PE) was 22.0%, and recurrence as PE was 10.6%. In 1365 patients with proximal DVT, the 5‐year recurrence rate was 26.4%, and recurrence with PE was 3.6%. The risk of recurrence as PE was 3.1‐fold greater in patients presenting with symptomatic PE than in patients with proximal DVT (HR, 3.1; 95% CI, 1.9–5.1). Patients with proximal DVT had a 4.8‐fold higher cumulative recurrence rate than those with distal DVT (HR, 4.8; 95% CI, 2.1–11.0). Conclusion: Whilst DVT and PE are manifestations of the same disease, the phenotypic expression is predetermined. Patients presenting with PE are three times more likely to suffer recurrence as PE than patients presenting with DVT. Patients presenting with calf DVT are at low risk of recurrence and at low risk of recurrence as PE.     

CT venography in suspected pulmonary thromboembolism.

Pulmonary embolism (PE) and deep venous thrombosis (DVT) are a continuum and are difficult to diagnose clinically. Combined CT venography and pulmonary angiography (CTVPA) is a single examination that combines multidetector CT pulmonary angiography (CTPA) and CT venography (CTV) of the abdomen, pelvis, and lower extremities, providing "one-stop shopping" for venous thromboembolism without additional venipuncture or i.v. contrast, and it adds only a few additional minutes to scanning time. CTVPA rapidly and accurately examines the deep veins, reveals the presence, absence, and extent of deep venous thrombosis, serves as a baseline, and helps guide patient management. Multiple investigators have reported a high degree of accuracy when CTV is compared with venous ultrasound. There are some pitfalls in image interpretation, especially with regard to mixing artifacts, and there are continuing controversies as to exactly which parts of the abdomen, pelvis, and legs should be scanned routinely, the ideal timing of CTV acquisition relative to contrast injection, and the slice thickness and gap, if any, that should be used.     

D-Dimer for venous thromboembolism diagnosis: 20 years later

Summary.  Twenty years after its first use in the diagnostic workup of suspected venous thromboembolism (VTE), fibrin D-dimer (DD) testing has gained wide acceptance for ruling out this disease. The test is particularly useful in the outpatient population referred to the emergency department because of suspected deep vein thrombosis (DVT) or pulmonary embolism (PE), in which the ruling out capacity concerns every third patient clinically suspected of having the disease. This usefulness is based on the high sensitivity of the test to the presence of VTE, at least for some assays. Due to its poor specificity precluding its use for ruling in VTE, DD testing must be integrated in comprehensive, sequential diagnostic strategies that include clinical probability assessment and imaging techniques such as lower limb venous compression ultrasonography for suspected DVT or multi-slice helical computed tomography for suspected PE. The present narrative review updates the data available on the use of the various commercially available DD assays in the diagnostic approach of clinically suspected VTE in distinct patient populations or situations, including outpatients and inpatients, patients with cancer, older age, pregnancy, a suspected recurrent event, limited thrombus burden, and patients already on anticoagulant treatment.