神经外科术后静脉栓塞症发病率及早期诊断

目的对神经外科术后患者静脉栓塞症（深静脉血栓和肺栓塞）发病率及早期诊断进行前瞻性研究。方法37例神经外科术后患者均按照静脉血栓预防指南进行了弹力袜和（或）四肢间隙气动压迫的预防性治疗。在术后平均12d进行血管彩色超声检查,并通过增强CT扫描明确诊断。结果本组研究中下肢深静脉血栓发生率为13．5％,在发生深静脉血栓患者中肺栓塞发生率为60％,所有静脉血栓患者在临床上均没有症状。结论在神经外科术后患者中静脉血栓症的发病率很高,在采用了预防措施后部分患者依然不能避免,早期预防和早期发现对于减少神经外科术后静脉栓塞症非常重要。     

Impact of thromboprophylaxis guidelines on clinical outcomes following total hip and total knee replacement

Background

The American College of Chest Physicians (ACCP) guidelines recommends thromboprophylaxis for total hip replacement (THR) and total knee replacement (TKR) patients. We examined alignment with ACCP thromboprophylaxis guidelines among THR/TKR patients, and compared symptomatic venous thromboembolism (VTE), bleeding event rates and risk factors for VTE between patients receiving ACCP-recommended thromboprophylaxis (‘ACCP’) and those who did not (‘non-ACCP’).

Methods

This retrospective observational study used a large US health plan claims database that was linked to an inpatient database containing detailed inpatient medication use and a database containing date-of-death information. Patients who had THR/TKR surgery between April 01, 2004 and December 31, 2006 were included. Comparisons of VTE and bleeding events between ACCP and non-ACCP patients were analyzed using chi-squared tests and multivariate logistic regression.

Results

Of 3,497 linked patients, 1,395 (40%) received ACCP recommended thromboprophylaxis. Of the patients who received non-ACCP recommended prophylaxis the majority (81%) received shorter than the recommended minimum 10 day prophylaxis and 118 (5.6%) of patients received no prophylaxis. Overall, non-ACCP patients were almost twice as likely to experience an incident DVT (3.76% versus 2.01%, p = 0.003) and more than eight times as likely to experience an incident PE (1.19% versus 0.14%, p = 0.001) relative to ACCP patients; there were no statistically significant difference in bleeding rates. Multivariate logistic regression indicated that the odds of a VTE event were significantly lower for ACCP patients (DVT: OR = 0.54; p = 0.006; PE: OR = 0.12; p = 0.004).

Conclusions

This study offers a unique perspective on ‘real-world’ thromboprophylaxis patterns and associated outcomes in THR and TKR patients in the US. It suggests that only 40% of THR/TKR patients receive ACCP-recommended thromboprophylaxis and that not receiving ACCP thromboprophylaxis is an independent risk factor for both DVT and PE.     

The treatment of venous thromboembolism with low-molecular-weight heparins. A meta-analysis

The currently recommended method of venous thromboembolism (VTE) treatment is the application of vitamin K antagonists (VKA) in most patients, and low-molecular-weight heparins (LMWH) in selected groups. The VKA dose adjustment is difficult which might well render the treatment ineffective. The study aimed to compare LMWH with VKA in treating VTE in terms of efficacy and safety. A systematic review of literature and the meta-analysis of the treatment results were performed. The main differences between LMWH and VKA in terms of their respective effectiveness in treating VTE consist in appreciably more advantageous effects of LMWH in preventing deep venous thrombosis (DVT). The key difference in terms of respective safety is the greater effectiveness of LMWH inpreventing minor bleedings. The advantage of LMWH in cancer patients consists predominantly in a significantly better protection against DVT episodes, whereas the advantage of LMWH in non-cancer patients is mainly owed to better protection against minor bleedings. In none of the analysed outcomes of VTE treatment, the application of VKA proved to hold any advantage over LMWH. Although, arguably, there might well be sufficient medical grounds to propose more widespread use of LMWH, it still remains a debatable issue whether the currently used therapeutic standard should also be modified accordingly. Apart from the actual findings of the present meta-analysis, pertinent economic considerations must also be addressed.     

Venous thromboembolism after Diaphragm Pacing in amyotrophic lateral sclerosis

Introduction: Patients with amyotrophic lateral sclerosis (ALS) are prone to venous thromboembolism (VTE) and secondary complications. Because there is an increased incidence of VTE after surgical procedures, placement of a Diaphragm Pacing System (DPS) in ALS patients as treatment for respiratory muscle weakness could potentially increase the incidence of VTE, especially in patients with limited mobility. Methods: We implanted a DPS in 10 ALS patients who met the criteria for this procedure. They underwent a preoperative evaluation as recommended by the guidelines. Results: We report 2 patients with no symptoms of deep vein thrombosis (DVT) before the surgical procedure who then developed perioperative VTE. Conclusions: These patients highlight the need to consider preoperative screening for DVT and postoperative thromboprophylaxis in high‐risk ALS patients who undergo DPS placement. Muscle Nerve 50 : 863–865, 2014     

Thromboprophylaxis in non-surgical cancer patients

Acutely ill medical patients with cancer and cancer patients requiring non-surgical therapy are considered as non-surgical cancer patients and are at moderate to high risk of venous thromboembolism (VTE): approximately 10-30% of these patients may develop asymptomatic or symptomatic deep-vein thrombosis (DVT) or pulmonary embolism (PE), and the latter is a leading contributor to deaths in hospital. Other medical conditions associated with a high risk of VTE include cardiac disease, respiratory disease, inflammatory bowel disease, rheumatological and infectious diseases. Pre-disposing risk factors in non-surgical cancer patients include a history of VTE, immobilisation, history of metastatic malignancy, complicating infections, increasing age, obesity hormonal or antiangiogenic therapies, thalidomide and lenalidomide therapy. Heparins, both unfractionated (UFH) and low molecular weight heparin (LMWH) and fondaparinux have been shown to be effective agents in prevention of VTE in the medical setting with patients having a history of cancer. UFH and LMWH along with semuloparin also have a role in outpatients with cancer receiving chemotherapy. However, it has not yet been possible to demonstrate a significant effect on mortality rates in this population. UFH has a higher rate of bleeding complications than LMWH. Thromboprophylaxis has been shown to be effective in medical patients with cancer and may have an effect on cancer outcomes. Thromboprophylaxis in patients receiving chemotherapy remains controversial and requires further investigation. There is no evidence for the use of aspirin, warfarin or mechanical methods. We recommend either LMWH, or fondaparinux for the prevention of VTE in cancer patients with acute medical illnesses and UFH for those with significant severe renal impairment. For ambulatory cancer patients undergoing chemotherapy we recommend LMWH or semuloparin. These are safe and effective agents in the thromboprophylaxis of non-surgical cancer patients.     

Venous thromboembolism in patients with active cancer

Patients with cancer have an increased risk of venous thromboembolism (VTE). To further define the demographics, comorbidities, and risk factors of VTE in these patients, we analyzed a prospective registry of 5,451 patients with ultrasound confirmed deep vein thrombosis (DVT) from 183 hospitals in the United States. Cancer was reported in 1,768 (39%), of whom 1,096 (62.0%) had active cancer. Of these, 599 (54.7%) were receiving chemotherapy, and 226 (20.6%) had metastases. Lung (18.5%), colorectal (11.8%), and breast cancer (9.0%) were among the most common cancer types. Cancer patients were younger (median age 66 years vs. 70 years; p < 0.0001), were more likely to be male (50.4% vs. 44.5%; p = 0.0005), and had a lower average body mass index (26.6 kg/m(2) vs. 28.9 kg/m(2); p < 0.0001). Cancer patients less often received VTE prophylaxis prior to development of DVT compared to those with no cancer (308 of 1,096, 28.2% vs. 1,196 of 3,444, 34.6%; p < 0.0001). For DVT therapy, low-molecular-weight heparin (LMWH) as monotherapy without warfarin (142 of 1,086, 13.1% vs. 300 of 3,429, 8.7%; p < 0.0001) and inferior vena caval filters (234 of 1,086, 21.5% vs. 473 of 3,429, 13.8%; p < 0.0001) were utilized more often in cancer patients than in DVT patients without cancer. Cancer patients with DVT and neurological disease were twice as likely to receive inferior vena caval filters than those with no cancer (odds ratio 2.17, p = 0.005). In conclusion, cancer patients who develop DVT receive prophylaxis less often and more often receive filters than patients with no cancer who develop DVT. Future studies should focus on ways to improve implementation of prophylaxis in cancer patients and to further define the indications, efficacy, and safety of inferior vena caval filters in this population.     

Long-term clinical follow-up in 265 patients with deep venous thrombosis initially treated with either unfractionated heparin or dalteparin: a retrospective analysis.

The primary objective of this retrospective study was to describe the frequency of a post-thrombotic syndrome in 265 patients previously treated for deep venous thrombosis (DVT). The secondary objectives were to document the frequency of recurrent venous thromboembolism (VTE) and mortality, especially from malignant disease. The patients were evaluated 5-14 years after inclusion in three randomized trials comparing continuous intravenous (i.v.) infusion of unfractionated heparin (UFH) (n = 85) with a low molecular weight heparin (LMWH), dalteparin (n = 180). The median post-thrombotic score at follow-up was 2 (range 0-8). In a multiple step-wise regression analysis the postthrombotic score was significantly higher among patients with initial proximal DVT (p = 0.0001) as compared with those who had distal DVT. A recurrent venous thromboembolic event was diagnosed in 29.4% of the patients treated with dalteparin and in 23.5% of the patients treated with UFH (ns). A secondary risk factor for venous thromboembolism and a longer duration of treatment with oral anticoagulants (OAC) were significantly associated with a lower risk for recurrent VTE, whereas malignant disease diagnosed during follow-up was associated with a higher risk. During follow-up a total of 40.7% of patients had died. No difference in total mortality or mortality from malignant disease was demonstrated between the two drugs. In conclusion, a severe post-thrombotic syndrome occured relatively infrequent. considering the long observation period. Proximal DVT was significantly associated with a more severe post-thrombotic syndrome. After 14 years follow-up, no significant differences were observed in overall mortality, mortality from malignant disease or recurrent VTE between UFH- and dalteparin-treated patients. Malignant disease was a risk factor for recurrent VTE, the presence of a secondary risk factor and a longer duration of treatment with OAC decreased the risk for recurrent VTE.     

Deep vein thrombosis after elective cesarean section

INTRODUCTION: Pregnancy is associated with an overall 5-10 fold increased risk of venous thromboembolism (VTE). The absolute risk is highest during and shortly after delivery. Although operative delivery further increases the risk of VTE, there is no consensus on thromboprophylaxis after an elective cesarean. The aim of the present study was to investigate the frequency of symptomatic and asymptomatic deep venous thrombosis (DVT) in a low risk cesarean section population. MATERIALS AND METHODS: Fifty-nine women undergoing elective cesarean section were screened for DVT using triplex Doppler sonography 3-5 days after delivery. Markers of activated coagulation were also followed and all women were screened for thrombophilia. Postoperative thromboprophylaxis was not given. During the same period all cases of symptomatic VTE were also recorded. RESULTS: No DVT was detected by ultrasonography and no women developed symptomatic VTE during the six weeks follow-up period after delivery. Six women had thrombophilia. During the study period, a cesarean section was performed in 1067/5364 (20%) deliveries. Five of these women (0.47%) developed symptomatic pulmonary embolism, and all of these women had additional risk factors for VTE. CONCLUSION: The risk of DVT among healthy pregnant women undergoing elective cesarean section is low, and general medical thromboprophylaxis is probably not justified.     

Managing venous thromboembolism in Asia: Winds of change in the era of new oral anticoagulants

Despite advances in the management of venous thromboembolism (VTE), treatment of many patients worldwide, especially in Asia, remains inadequate and/or discordant with prevailing guidelines. Although epidemiological studies consistently report lower incidences of VTE in Asians than Caucasians, VTE rates in Asia have probably been gravely underestimated, partly due to comparatively lesser ascertainment. It is becoming evident that Asians are at much higher risk of VTE than was hitherto supposed. Nevertheless, VTE risk-assessment is not routine in Asia and thromboprophylaxis rates are much lower than in Western nations.It is important to base decisions about anticoagulation on individual circumstances and weigh the potential benefits and risks. The conventional VTE management paradigm is not ideal. New oral anticoagulants offer advantages over current modalities that may help to streamline patient care and reduce healthcare costs. Initially, they will be mainly used in uncomplicated cases and, in the absence of clear differences in efficacy or safety, convenience, tolerability/adherence and cost will determine treatment choice.There is clear scope to improve VTE prevention and treatment in Asia. Key priorities are raising awareness of best practice and properly implementing guidelines. Uncertainty about the burden of VTE and concern about bleeding are barriers. High-quality Asian epidemiological data are needed to guide healthcare policy and evidence-based practice. More data on the occurrence and management of bleeding complications in Asian patients are also required. Meanwhile, physicians should remain vigilant and strive to act early, decisively and appropriately to diagnose and treat VTE, particularly in patients at high risk.     

Apixaban decreases coagulation activity in patients with acute deep-vein thrombosis

In patients with acute deep-vein thrombosis (DVT), apixaban, a direct oral factor Xa inhibitor, showed efficacy and safety similar to low-molecular-weight heparin followed by vitamin K antagonist (LMWH/VKA). We evaluated biomarkers of coagulation activity in relation to treatment dose, duration and clinical outcome. Patients (N = 520) with symptomatic DVT were randomised to receive apixaban (5 mg bid, 10 mg bid or 20 mg qd) or LMWH/VKA for 12 weeks. Plasma D-dimer, prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complex (TAT) levels were measured at baseline, and weeks 3 and 12 after treatment. Median plasma levels of D-dimer, F1+2 and TAT were elevated at baseline. At weeks 3 and 12, biomarker levels were normalised in most patients in all treatment groups, consistent with the low rate of venous thromboembolism (VTE) observed. Median reduction in D-dimer was similar in all treatment groups; percentage of patients with D-dimer above upper limit of normal decreased from 95% to 24-40% at week 12. F1+2 decline was greater with LMWH/VKA than apixaban. F1+2 in the apixaban groups changed to a similar extent (>84% of patients had F1+2 within reference range at week 12). Magnitude of TAT reduction was not quantifiable. In conclusion, levels of coagulation biomarkers decreased over 12 weeks of treatment with apixaban or LMWH/VKA in most patients with acute VTE. Baseline D-dimer and F1+2 were higher in patients with recurrent symptomatic VTE than in those without. Plasma levels of coagulation biomarkers did not appear to correlate with total bleeding events.     

Prospective evaluation of coagulation activation in pregnant women receiving low-molecular weight heparin

Pregnancy is a major risk factor for venous thromboembolism (VTE), and low-molecular weight heparin (LMWH) seems to be safe and effective in pregnant women. Normal pregnancy is accompanied by a state of hypercoagulability, indicated by an increase in markers of coagulation activation. In a prospective cohort study, we followed 61 women who received LMWH thromboprophylaxis throughout pregnancy because of a history of VTE, hereditary thrombophilia and/or previous pregnancy-related complications. The control group consisted of 113 healthy pregnant women without antithrombotics. D-Dimer, prothrombin fragment F1+2 (F1+2) and the resistance to activated protein C (APC-ratio) were measured in all women during the first, second and third trimester. Patients and controls did not significantly differ with regard to baseline characteristics and pregnancy outcome. A (recurrent) VTE was seen in one patient despite LMWH. D-Dimer levels significantly increased among patients and controls during pregnancy (p < 0.0001), and were significantly higher among patients compared with the controls (p <0.0001) [395 ng/ml (95% CI 340-458) and 249 ng/ml (95%CI 234-266); 710 ng/ml (95% CI 602-838) and 475 ng/ml (95% CI 431-523); 1089 ng/ml (95% CI 931-1273) and 822 ng/ml (95% CI 741-911); respectively]. Levels of F1+2 significantly increased while the APC-ratio significantly decreased during pregnancy among patients and controls. Despite LMWH, pregnancy is accompanied by a substantial activation of the coagulation system.     

Long-term therapy with low-molecular-weight heparin in cancer patients with venous thromboembolism

Long-term therapy with low-molecular-weight heparin (LMWH) is the treatment of choice for cancer patients with venous thromboembolism (VTE). However, the ideal doses of LMWH have not been thoroughly studied. We used the RIETE Registry data to assess the influence of the daily LMWH dosage on outcome during the first three months after VTE. We used propensity score-matching to compare patients who received <150 vs. those receiving ≥150 UI/kg/day LMWH. Up to July 2010, 3,222 cancer patients with VTE received long-term therapy with fixed doses of LMWH. Of these, 1,472 (46%) received <150 IU/kg/day (mean, 112 ± 28), and 1,750 received ≥150 IU/kg/day (mean, 184 ± 32). Results of the propensity score matching involved 1269 matched pairs. During follow-up, the incidence of pulmonary embolism (PE) recurrences was similar (1.2% vs. 1.9%), but patients receiving <150 IU/kg/day LMWH had a lower incidence of fatal PE than those treated with ≥150 IU/kg/day (0.2% vs. 1.0%; p=0.004). Multivariate analysis confirmed that patients receiving <150 IU/kg/day LMWH had a lower risk for fatal PE (odds ratio [OR]: 0.2; 95% confidence interval [CI]: 0.06-0.8) and for major bleeding (OR: 0.6; 95% CI: 0.3-1.0) than those treated with ≥150 IU/kg/day. In real life, one in every two cancer patients with VTE received lower doses of LMWH than those used in randomised trials, with large variations from patient to patient. Unexpectedly, patients treated with <150 IU/kg/day LMWH had fewer fatal PE cases and fewer major bleeding events than those receiving ≥150 IU/kg/day LMWH. This finding, however, should be validated in prospective clinical trials.     

Thromboprophylaxis in medical patients: the role of low-molecular-weight heparin

Many hospitalised medical patients are at increased risk of venous thromboembolism (VTE). Consensus statements recommend that such patients be assessed for risk of VTE on admission to hospital and receive thromboprophylaxis where appropriate. However, VTE prophylaxis is not widely used in medical patients. One explanation is that assessing medical patients' risk of VTE is complicated. The risk depends not only on the current illness but also on multiple intrinsic factors, and a variety of strategies for identifying patients who should receive thromboprophylaxis have been suggested. Thromboprophylaxis with unfractionated heparin (UFH) has proved to be effective in reducing the incidence of deep-vein thrombosis and overall mortality in medical patients. Clinical trial evidence, including a meta-analysis, suggests that thromboprophylaxis with low-molecular-weight heparin (LMWH) is at least as effective as with UFH, and also has the advantage of fewer bleeding complications. In particular, two large, randomised clinical trials--Prophylaxis in Medical Patients with Enoxaparin (MEDENOX) and Prospective Evaluation of Dalteparin Efficacy for Prevention of VTE in Immobilized Patients Trial (PREVENT)--showed that thromboprophylaxis with the LMWHs enoxaparin (40 mg s.c. once daily) or dalteparin (5,000 IU once daily) is more effective than placebo and well tolerated in medical patients. In addition, the Thromboembolism-Prevention in Cardiopulmonary Diseases with Enoxaparin (THE-PRINCE) trial showed that enoxaparin treatment was as effective as UFH. These studies provide solid evidence for the widespread use of thromboprophylaxis in medical patients.     

Asia-Pacific Thrombosis Advisory Board consensus paper on prevention of venous thromboembolism after major orthopaedic surgery

The incidence of postoperative venous thromboembolism (VTE) in Asian populations is generally thought to be lower than in Western populations, and the use of thromboprophylaxis after surgery is not routine. This paper is authored by the Asia-Pacific Thrombosis Advisory Board. To provide guidance on the most effective postoperative thromboprophylaxis management, this paper reviews the available data on the incidence of VTE in Asian populations, considers current clinical guidelines for the prevention of VTE to determine whether these guidelines are applicable to Asian populations, and evaluates the potential of new thromboprophylactic agents. Based on the available evidence, it was agreed that VTE represents a genuine problem in Asian patients, although the exact incidence in local populations requires confirmation in large, well-designed clinical trials. Furthermore, there was consensus that current guideline recommendations for the routine use of postoperative thromboprophylaxis should be implemented in Asia, and that new oral agents now available represent an effective and potentially more convenient therapeutic option. In conclusion, we call for recognition that VTE is an issue in Asian patients, and that effective thromboprophylaxis is the most important strategy.     

Role of new anticoagulants for the prevention of venous thromboembolism after major orthopaedic surgery and in hospitalised acutely ill medical patients

Anticoagulation therapy for the prevention of venous thromboembolic events is indicated in patients after major orthopaedic surgery and in hospitalised acutely ill medical patients, who have a high or moderate risk of venous thromboembolism (VTE), respectively. Clinical trials have clearly demonstrated that short-term anticoagulation reduces the risk of VTE in these patient groups and that longer-term anticoagulation is beneficial for some indications. Evidence-based guidelines for thromboprophylaxis have been developed based on these studies. However, despite these guidelines, thromboprophylaxis is still underused, or used suboptimally, in many patients. This is, in part, because of the limitations of traditional anticoagulants such as unfractionated heparin, low- molecular-weight heparin, synthetic pentasaccharides, and vitamin K antagonists. Newer oral anticoagulants, such as rivaroxaban, apixaban, and dabigatran etexilate, have certain advantages over traditional agents. They can be administered orally at a fixed dose without routine coagulation monitoring and have minimal food and drug interactions. These characteristics may result in better adherence to guidelines and improved patient outcomes. This review provides an overview of phase III clinical trial data for these newer anticoagulants in major orthopaedic surgery and in hospitalised acutely ill medical patients, and discusses their potential for extended use in the post-hospital discharge setting. All three newer oral anticoagulants are approved in many countries for the prevention of VTE after hip replacement or knee replacement surgery in adult patients, and it is likely that these drugs will contribute considerably towards reducing the substantial healthcare burden associated with VTE.     

Sticker reminders improve thromboprophylaxis appropriateness in hospitalized patients

Background

Venous thromboembolism (VTE) is a major health problem. Even though effective thromboprophylaxis measures exist to prevent VTE, close adherence to guidelines is missing. We assessed the effects of pasting VTE prophylaxis sticker reminders, on the appropriateness of thromboprophylaxis and prophylaxis underutilization.

Methods

Thromboprophylaxis reception was sought prospectively in two time points before and two time points after pasting sticker reminders in hospitalized patients of Masih Daneshvari Medical Center, Tehran, Iran. Thromboprophylaxis reception appropriateness was evaluated by the eighth American College of Chest Physicians (ACCP) guidelines on antithrombotic and thrombolytic therapy. Co-morbidities and conditions considered to affect the risk of venous thromboembolism were also recorded.

Results

Prophylaxis reception and appropriateness were studied in 298 patients before and 306 patients after the intervention. Based on the ACCP guidelines, overall thromboprophylaxis appropriateness was improved after the intervention (70.4% before, and 78.1% after the intervention, P = 0.03). Prophylaxis underutilization, and prophylaxis initiation delay in those who needed thromboprophylaxis, were also reduced (P = 0.03, and P = 0.011 respectively). The intervention did not result in an increased rate of overprophylaxis (P = 0.45).

Conclusion

Sticker reminders could be safely and effectively incorporated into strategies to improve VTE prophylaxis and prophylaxis appropriateness, particularly in healthcare settings where electronic alert systems are not available.     

Hematologic malignancies and thrombosis

Patients with hematologic malignancies have an increased risk of venous thromboembolism (VTE), particularly at diagnosis and during the treatment with chemotherapy, asparaginase or immunomodulatory drugs (IMiDs). A disease-dependent hypercoagulable condition associated with other risk factors like drugs, central venous catheter (CVC), immobility and infections are responsible for this high VTE rate. Thrombotic complications have a significant impact on morbidity and in some cases also on mortality of patients with onco-hematologic diseases, therefore thromboprophylaxis to prevent VTE in this setting is needed. However, thrombocytopenia and hemorrhagic complications pone many difficulties in the management of an anticoagulant or antiaggregant treatment in these patients. Recommendations from current guidelines are limited to multiple myeloma patients treated with thalidomide or lenalidomide associated with dexamethasone or chemotherapy, but hematological clinical departments should implement a policy for prevention and treatment of thromboembolic complications in hematologic malignancies.     

Efficacy and Safety of Anticoagulant Therapy for the Treatment of Acute Cancer-Associated Thrombosis: A Systematic Review and Meta-Analysis

Background

Current clinical practice guidelines all recommend the use of therapeutic doses of low molecular weight heparins (LMWH) for the initial and long-term treatment of cancer-related thrombosis. The use of vitamin-K antagonists (VKA) is acceptable if LMWH is not available. Direct oral anticoagulants (DOACs) have been shown to be comparable to conventional therapy for the acute treatment of VTE but their efficacy and safety in cancer patients remains uncertain.

Methods

A systematic literature search strategy was conducted using MEDLINE, EMBASE, and the EBM reviews. Randomized controlled trials (RCTs) reporting rates of recurrent VTE and major bleeding in cancer patients were included. Relative risks (RR) (95% confidence intervals (CI)) for these outcomes were generated.

Results

A total of 9 RCTs (2310 patients) were included in our analysis. In comparison to VKA, LMWH showed a significant reduction in recurrent VTE events (RR: 0.52; 95% CI: 0.36 to 0.74) whereas DOACs did not (RR: 0.66; 95% CI: 0.39 to 1.11). LMWH was associated with a non significant increase in the risk of major bleeding (RR: 1.06; 95% CI: 0.5 to 2.23) whereas DOACs showed a non significant reduction (RR: 0.78; 95% CI: 0.42 to 1.44). Annualized risks of recurrent VTE and major bleeding among patients randomized to VKA were higher in the LMWH studies as compared to the studies assessing DOACs suggesting that a higher risk cancer population were enrolled in the LMWH studies.

Conclusions

LMWH should be used for the treatment of acute cancer-associated thrombosis. The use DOACs cannot be supported until trials comparing them to LMWH are conducted.     

Incidental venous thromboembolism in cancer patients: prevalence and consequence

Introduction

Careful re-evaluation of CT-scans for cancer staging frequently reveals unsuspected venous thromboembolism (VTE) on CT-scans. However, it is unknown how often these findings lead to anticoagulant treatment in daily clinical practice.

Methods

Reports from thoracic and/or abdominal CT-scans performed in a consecutive series of patients to stage cancer were retrospectively evaluated to determine the prevalence of incidental venous thromboembolism (iVTE). Presence of pre-existing signs of VTE, anticoagulant treatment and 3-month follow-up were analysed in patients with iVTE.

Results

A total of 1466 staging scans (838 patients) from the year 2006 were included in the analysis. The prevalence of VTE in patients was 2.5% (21/838 patients, 95% confidence interval 1.6-3.8%); the prevalence of VTE on scans was 1.4% (21/1466 scans, 95% CI 0.9-2.2%). Incidental PE or deep vein thrombosis (DVT) was observed in 11 (1.3%, 0.7-2.3%) and abdominal vein thrombosis in 9 patients (1.1%, 0.6-2.0%; in the portal (5), mesenteric (3) and renal vein (1), respectively). Nine out of eleven patients with PE/DVT were treated with anticoagulants, while none of the patients with thrombosis in other locations received anticoagulants. One of these patients developed symptomatic PE one month later; otherwise, follow up was uneventful in the untreated patients.

Conclusion

The prevalence of iVTE in patients with cancer in clinical practice is relatively low and most patients with PE or DVT are treated with anticoagulants. For patients with thrombi in other locations, further research is necessary to understand the natural history of these thrombi in order to develop adequate guidelines.     

Prophylaxis of deep venous thrombosis and adherence to guideline recommendations among inpatients with acute stroke: results from a multicenter observational longitudinal study in China

INTRODUCTION: Deep venous thrombosis (DVT) is a common complication in acute stroke. Evidence-based guidelines recommend the use of prophylactic heparins in patients with risk of DVT. We aimed to evaluate the clinical practices for DVT prophylaxis in acute stroke inpatients enrolled in a multicenter observational longitudinal study on deep venous thrombosis (Incidence of Deep Venous Thrombosis after Acute Stroke in China, INVENT-China). MATERIALS AND METHODS: Patients' characteristics and DVT prophylaxis was extracted from the database of INVENT-China. Appropriate adherence to the guidelines was analysed. RESULTS: Six hundred and fifty-six patients with acute stroke were eligible for analysis in this study. Pharmacologic prophylaxis with low-molecular-weight heparins (LMWH) was applied to 18 patients with ischemic stroke (3.4%) and one patient with cerebral hemorrhage. Independent factors associated with use of prophylactic anticoagulant treatment were stroke subtype (OR=0.07, 95% CI=0.01-0.78, p=0.03), baseline NIHSS score (OR=0.25, 95% CI=0.07-0.95, p=0.04), baseline motor leg function (NIHSS score) (score=1, OR=0.16, 95% CI=0.03-0.79, p=0.025; score=2, OR=0.20, 95% CI=0.05-0.84, p=0.028; score=3, OR=0.23, 95% CI=0.06-0.91, p=0.037; score=4, reference), diabetes mellitus (OR=3.86, 95% CI=1.39-10.72, p=0.009), malignancy (OR=9.55, 95% CI=1.98-46.2, p=0.005), varicose veins (OR=12.48, 95% CI=1.64-94.9, p=0.015) and central venous catheterization (OR=6.96, 95% CI=1.36-35.79, p=0.02). CONCLUSION: Thromboprophylaxis is inadequate in acute stroke inpatients in China. Guidelines for prevention DVT in acute stroke should be established and efforts should be made to improve venous thromboembolism prophylaxis practice.