Racial and gender differences in the incidence of recurrent venous thromboembolism

Men have been reported to have a higher incidence of recurrent venous thromboembolism than women. However, it is not known if this gender effect holds among different racial/ethnic groups and for both venous thrombosis and pulmonary embolism. We conducted a retrospective analysis of 18- to 65-year-old Caucasian, African-American and Hispanic cases hospitalized in California with unprovoked venous thromboembolism. The principal outcome was recurrent venous thromboembolism 7-60 months after the index event. Among 11,514 cases that were followed for a mean of 3.0 years, men had a significantly higher rate (events/100 patient-years) of recurrent venous thromboembolism than women for both venous thrombosis [rate ratio (RR) = 1.5, 95% confidence interval (CI):1.3-1.8] and pulmonary embolism [RR = 1.3, 95%CI:1.0-1.6]. Among men the recurrence rate did not vary significantly between the racial/ethnic groups (p > 0.05). However, the recurrence rate among Hispanic women with venous thrombosis was significantly higher than in Caucasian women (p < 0.001) and was comparable to the rate in men. Both Hispanic and African-American women with pulmonary embolism had a higher recurrence rate compared with Caucasian women (p < 0.02) that was comparable to the rate in men. We conclude that women in California had a 40% lower risk of recurrent venous thromboembolism compared to men. Rates were comparable among men of different races, but there were significant inter-racial differences among women, which also varied with the type of initial event. The effect of gender on the risk of recurrent venous thromboembolism can not be generalized because it varies between racial/ethnic groups and with the type of index event.     

Low-molecular-weight heparin: the optimal duration of prophylaxis against postoperative venous thromboembolism after total hip or knee replacement

Venous thromboembolism is a major health problem. In about 20% of cases, the initial clinical manifestation of venous thromboembolism is sudden death due to pulmonary embolism. Consequently, appropriate prophylaxis is critical in order to improve survival. Because patients with recent surgery have a 22-fold increased risk of postoperative venous thromboembolism, a large research effort has been directed toward identifying the safest and most effective prophylaxis after surgery, especially after total hip or knee replacement. While low-molecular-weight heparin is the most effective prophylaxis currently available, from 15% to 30% of hip or knee replacement patients still develop deep vein thrombosis by the time of hospital discharge, and another 25% develop new deep vein thrombosis by 3 weeks after discharge. Extended out-of-hospital low-molecular-weight heparin prophylaxis can safely reduce the prevalence of deep vein thrombosis by about 50%. However, essentially all of these thrombi are small, asymptomatic, and resolve without serious clinical sequelae. Based on one clinical trial, out-of-hospital low-molecular-weight heparin prophylaxis could reduce the incidence of symptomatic venous thromboembolism or all-cause death after discharge by a maximum of 2.2%. At current drug costs, universal out-of-hospital low-molecular-weight heparin prophylaxis is unlikely to be cost-effective. For most patients, 7 to 10 days of low-molecular-weight heparin prophylaxis is adequate. Future research should be directed at identifying patients at risk for out-of-hospital venous thromboembolism, and targeting extended prophylaxis to those at highest risk.     

Outpatient treatment of pulmonary embolism with dalteparin

BACKGROUND: Pulmonary embolism is a common complication of deep vein thrombosis. It has been established that low molecular weight heparin may be used to treat deep vein thrombosis or pulmonary embolism and randomized studies have established that outpatient management of deep vein thrombosis with low molecular weight heparin is at least as effective as in-hospital management with unfractionated heparin. METHODS: This was a prospective cohort study of eligible patients with pulmonary embolism managed as outpatients using dalteparin (200 U/kg s/c daily) for a minimum of five days and warfarin for 3 months. Outpatients included those managed exclusively out of hospital and those managed initially for 1-3 days as inpatients who then completed therapy out of hospital. Reasons for admission included hemodynamic instability; hypoxia requiring oxygen therapy; admission for another medical reason; severe pain requiring parenteral analgesia or high risk of major bleeding. Patients were followed for three months for clinically apparent recurrent venous thromboembolism and bleeding. RESULTS: Between three teaching hospitals, a total of 158 patients with pulmonary embolism were identified. Fifty patients were managed as inpatients and 108 as outpatients. Of the outpatients, 27 were managed for an average of 2.5 days as inpatients and then completed dalteparin therapy as outpatients. The remaining 81 patients were managed exclusively as outpatients with dalteparin. For all outpatients the overall symptomatic recurrence rate of venous thromboembolism was 5.6% (6/108) with only 1.9% (2/108) major bleeds. There were a total of four deaths with none due to pulmonary embolism or major bleed. CONCLUSIONS: This prospective study suggests that outpatient management of pulmonary embolism is feasible and safe for the majority of patients.     

Thrombophilic abnormalities and recurrence of venous thromboembolism in patients treated with standardized anticoagulant treatment

INTRODUCTION: Whether patients with hereditary or acquired thrombophilia have an increased risk for recurrence of venous thromboembolism (deep vein thrombosis and/or pulmonary embolism) is still controversial. The aim of this study was to evaluate the incidence of recurrence of venous thromboembolism in patients with and without thrombophilic abnormalities treated with standardized anticoagulant treatment. MATERIAL AND METHODS: Database was from a prospective multicenter randomized study aimed at evaluating the long-term clinical benefit of extending to 1 year the 3-month oral anticoagulant treatment after a first episode of idiopathic proximal deep vein thrombosis. The screening for thrombophilia included antithrombin, protein C, protein S deficiencies, resistance to activated protein C and/or factor V R506Q mutation, the mutation 20210GA of the prothrombin gene, hyperhomocysteinemia and antiphospholipid antibodies. The diagnosis of venous thromboembolism recurrence was done by objective tests and adjudicated by a panel unaware of the results of the thrombophilia screening. RESULTS: A screening for thrombophilic abnormalities was performed in 195 patients. Twenty of 57 (35.1%) thrombophilic patients experienced a recurrence of venous thromboembolism as compared with 29 of 138 (21.0%) patients without thrombophilia (HR=1.78, 95% CI 1.002-3.140, p=0.046). The difference in VTE recurrence between patients with and without thrombophilia was accounted for by those who received 3 months of oral anticoagulation (HR=3.21, 95% CI 1.349-7.616, p=0.008). No difference between thrombophilic and non-thrombophilic patients was observed in the time interval from the index episode to recurrent venous thromboembolism (29.1+/-23.9 and 30.6+/-19.8 months, respectively). CONCLUSIONS: Thrombophilic abnormalities are associated with an increased risk of venous thromboembolism recurrence. The role of thrombophilia in the long-term management of venous thromboembolism should be addressed in prospective management studies.     

Diagnostic issues of VTE in pregnancy

Venous thromboembolism is a major cause of maternal morbidity and mortality, and accurate diagnostic workup upon suspicion of deep vein thrombosis or pulmonary embolism in a pregnant woman is of utmost importance. The diagnostic repertoire for venous thromboembolism is, however, less well studied in pregnant women. The clinical assessment is influenced by common symptoms of pregnancy such as leg swelling or shortness of breath. The role of D-Dimer is limited, since — even during uncomplicated pregnancy — D-Dimer levels increase with gestational age. Preliminary data indicate that a normal D-Dimer in a healthy pregnant woman with a low clinical probability may exclude deep vein thrombosis. Compression ultrasonography and ventilation perfusion scanning or helical computed tomography are the imaging techniques of choice in a pregnant woman with suspected deep vein thrombosis or pulmonary embolism, respectively. The role of magnetic resonance imaging for the diagnosis of venous thromboembolism during pregnancy is uncertain and contraindications particularly to contrast media have to be considered.     

Paradoxical Cerebral Embolism as Initial Manifestation of Chronic Thromboembolic Pulmonary Hypertension: A Case Report

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by chronic thrombi in the pulmonary arteries, causing pulmonary hypertension and right heart failure. Early and accurate diagnosis are essential for successful treatment but are often difficult because clinical signs and symptoms can be nonspecific and risk factors, such as history of venous thromboembolism, may not always be present. Here, we report a case involving a 76-year-old woman who demonstrated paradoxical cerebral embolism as the initial manifestation of CTEPH. She developed right hemiplegia without dyspnea or edema. Brain magnetic resonance imaging revealed multiple fresh infarctions, while transesophageal echocardiography revealed a patent foramen ovale. Based on these findings, she was diagnosed as having paradoxical cerebral embolism. During the search for the embolic source, right heart catheterization showed significant pulmonary hypertension and pulmonary angiography revealed chronic thrombi in the peripheral pulmonary arteries, consistent with a diagnosis of CTEPH. To our knowledge, this is the first case of CTEPH to be diagnosed with the onset of paradoxical cerebral embolism. Because CTEPH is the only potentially curable form of pulmonary hypertension, clinicians should consider paradoxical cerebral embolism as a possible initial manifestation of CTEPH.     

Is the prevalence of the factor V Leiden mutation in patients with pulmonary embolism and deep vein thrombosis really different?

INTRODUCTION: Previous investigations have suggested a lower prevalence of the factor V Leiden mutation in patients with pulmonary embolism, as compared to patients with deep leg vein thrombosis. METHODS: We studied unselected patients with pulmonary embolism, in whom we also assessed the presence of deep vein thrombosis by ultrasonography. We assessed the prevalence of heterozygosity for the factor V Leiden mutation and compared the outcome of patients with a normal ultrasound (primary pulmonary embolism) to those with an abnormal ultrasound (combined form of venous thromboembolism). Furthermore, we performed a literature search to identify all articles regarding the prevalence of heterozygous factor V Leiden mutation in patients with primary deep vein thrombosis, primary pulmonary embolism and a combined form of venous thromboembolism. We calculated a (common) odds ratio for these 3 manifestations of venous thromboembolism, including the current findings. RESULTS: In 92 patients with proven pulmonary embolism, 25 (27%) had also an abnormal ultrasound. In these patients, the prevalence of the factor V Leiden mutation was 24% (95% CI 9%-45%), whereas the mutation was present in 5 of 67 patients with primary pulmonary embolism (7%; 95% CI 2%-16%). The literature analysis indicated the common odds ratio for the presence of heterozygous factor V Leiden mutation in patients with primary deep vein thrombosis, primary pulmonary embolism and the combined form of venous thromboembolism to be 7.9 (95% CI 5-12), 3.5 (95% CI 2-6) and 6.8 (95% CI 3-14), respectively. CONCLUSION: In patients with primary pulmonary embolism the prevalence of the factor V Leiden mutation appears to be half of that reported in patients with primary deep vein thrombosis. The mechanism remains unclear.     

The epidemiology of venous thromboembolism in the community

The incidence of venous thromboembolism exceeds 1 per 1000; over 200,000 new cases occur in the United States annually. Of these, 30% die within 30 days; one-fifth suffer sudden death due to pulmonary embolism. Despite improved prophylaxis, the incidence of venous thromboembolism has been constant since 1980. Independent risk factors for venous thromboembolism include increasing age, male gender, surgery, trauma, hospital or nursing home confinement, malignancy, neurologic disease with extremity paresis, central venous catheter/transvenous pacemaker, prior superficial vein thrombosis, and varicose veins; among women, risk factors include pregnancy, oral contraceptives, and hormone replacement therapy. About 30% of surviving cases develop recurrent venous thromboembolism within ten years. Independent predictors for recurrence include increasing age, obesity, malignant neoplasm, and extremity paresis. About 28% of cases develop venous stasis syndrome within 20 years. To reduce venous thromboembolism incidence, improve survival, and prevent recurrence and complications, patients with these characteristics should receive appropriate prophylaxis.     

Inherited thrombophilia and first venous thromboembolism during pregnancy and puerperium

Venous thromboembolism is a rare but threatening complication of pregnancy. Little conclusive information is available on the actual risk of venous thromboembolism during pregnancy or puerperium in women with inherited thrombophilia, particularly in carriers of factor V Leiden and of the G20210A prothrombin gene mutation. To determine the pregnancy-related and puerperium-related risk of venous thromboembolism in women with inherited thrombophilia, we performed a case-control study on 119 women who had a first episode of deep vein thrombosis and/or pulmonary embolism during pregnancy or puerperium and 232 healthy women who had at least one pregnancy without thrombosis. Inherited thrombophilia was diagnosed in 47 patients (39.5%) and 15 controls (6.5%). The relative risk of venous thromboembolism was 10.6 (95% CI, 5.6-20.4) for heterozygous carriers of factor V Leiden, 2.9 (95% CI, 1.0-8.6) for heterozygous carriers of the prothrombin mutation and 13.1 (95% CI, 5.0-34.2) for those with antithrombin, protein C or protein S deficiency taken together. Sixty-eight of the 119 women (57%) had thrombosis after delivery, confirming the puerperium as a particularly high-risk period. When women were divided into two groups of those with antenatal or postnatal thrombosis. the relative risks associated with each type of inherited thrombophilia were of similar magnitude. In conclusion, women with inherited thrombophilia have an increased risk of venous thromboembolism during pregnancy. Among thrombophilic abnormalities, the prothrombin mutation was the weakest risk factor. Thrombosis occurred more frequently in puerperium than in pregnancy, whether or not thrombophilia was diagnosed.     

Symptomatic venous thromboembolism in acute leukemia. Incidence, risk factors, and impact on prognosis

The association between malignant disorders and occurrence of venous thromboembolism is well established. Patients with cancer and venous thromboembolism have adverse prognosis. No systematic study on the incidence and prognostic impact of venous thromboembolism in acute leukemia has been performed as yet. We retrospectively evaluated the incidence of symptomatic venous thromboembolism before chemotherapy in 719 patients (371 males and 348 females, median age of 57.4 years), diagnosed with acute leukemia [534 with acute myelogenous leukemia, 185 with acute lymphoblastic leukemia]. Furthermore, the relationship of venous thromboembolism to clinical and laboratory parameters and its impact on prognosis was assessed. Fifteen patients (2.09%) had venous thromboembolism (objectively confirmed in 13 patients) in close temporal relationship to the onset of acute leukemia. The incidence of venous thromboembolism was the same in acute myelogenous and lymphoblastic leukemia. In five patients, pulmonary embolism was documented. Venous thromboembolism occurred in all subtypes of acute leukemia, but was most common in promyelocytic leukemia. All but one patient were treated with anticoagulants. No patient died from treatment-related bleedings or venous thromboembolism. Overall, survival, disease-free survival, and remission duration did not differ between the patient groups with and without venous thromboembolism. In contrast to solid tumors, venous thromboembolism before or at diagnosis of acute leukemia is not associated with poor prognosis.     

Incidence of venous thromboembolism: a community-based study in Western France. EPI-GETBP Study Group. Groupe d'Etude de la Thrombose de Bretagne Occidentale

The incidence of venous thromboembolism has been studied during one year in a defined population of 342,000 inhabitants. The overall incidence (95% confidence interval) of venous thromboembolism was found to be 1.83 per thousand per year (1.69 to 1.98). The incidences of deep venous thrombosis and pulmonary embolism were 1.24 per thousand per year (1.12 to 1.36) and 0.60 per thousand per year (0.52 to 0.69), respectively. The incidence of venous thromboembolism rose markedly with increasing age for both sexes; over the age of 75, the annual incidence reached 1 per 100. Sixty three percent of the patients were at home when venous thromboembolism occurred. Of these, sixteen percent had been previously hospitalised within three months. These results raise concerns on identification of medical patients at high risk and effective prophylaxis.     

Thromboembolic complications in membranous nephropathy patients with nephrotic syndrome-a prospective study

Background

Venous thromboembolism (VTE) is one of the most serious complications in membranous nephropathy (MN). We investigate the incidence of VTE in MN patients with nephrotic syndrome (NS).

Methods

A total of 100 MN patients with NS were enrolled into this prospective study. The diagnosis of VTE was based on contrast-enhanced dual source computed tomography angiography.

Results

Venous thromboembolism was demonstrated in 36 patients (36%). 33 patients (33%) had renal vein thrombosis (RVT), 17 patients (17%) had pulmonary embolism (PE).　Flank pain was noted in 5 patients and gross hematuria in 2 patients with RVT. Dyspnea and chest pain were present in 9 patients with PE. The positive predictive value for D-dimer level was 69.4%, negative predictive value for D-dimer level was 96.1% in patients with MN. Of all the risk factors presented, D-dimer level, proteinuria, the ratio of proteinuria to serum albumin were independent risk factors for the development of VTE (P < 0.05), but the plasma level of antithrombin Ш was not correlated with VTE in this study. In follow up, venous thrombosis disappeared after anticoagulant treatment with low-molecular-weight heparins in 28 patients.

Conclusion

Venous thromboembolism was confirmed in 36% of MN patients with NS. Renal vein thrombosis and pulmonary embolism are common and usually asymptomatic. Computed tomography angiography can be used effectively to examine suspected patients. Measurement of D-dimer is helpful in VTE diagnosis. It is important that clinicians are aware that VTE should be considered as a common complication in MN patients with NS.     

Exclusion of venous thromboembolism: evaluation of D-Dimer PLUS for the quantitative determination of D-dimer

The objective of this study was to evaluate if D-Dimer PLUS (Dade Behring, USA), a rapid fully automated assay, could be used as an initial screening test in the diagnosis of venous thromboembolism (VTE). Samples from 274 consecutive symptomatic patients with suspected pulmonary embolism (n=229; 79% outpatients, 21% inpatients), deep venous thrombosis (n=37; 84% outpatients, 16% inpatients) or suspected for both complications (n=8) were tested with this D-dimer assay with a Sysmex CA-1500 Coagulation Analyzer. Clinical probability for pulmonary embolism (PE) or deep venous thrombosis (DVT) was staged according to a pretest risk score proposed by Wells. Final diagnosis of PE and/or DVT was established by spiral-computed tomography of the pulmonary arteries or compression ultrasonography, respectively. PE was diagnosed in 13.5% of the patients, whereas DVT was confirmed in 17.7% of the patients. The optimal cut-off value for exclusion of venous thromboembolism was 130 mug/l, and sensitivity, specificity and negative predictive value (NPV) were 95.0% (95% CI: 92.4-97.6), 30.4% (95% CI: 25.0-35.8) and 97.2% (95% CI: 95.2-99.2), respectively. In fact, two patient with PE were missed using D-Dimer PLUS; both cases were outpatients. In conclusion, this assay appears to be safe when implemented in an algorithm based on clinical assessment, D-dimer concentration, and radiological diagnostic techniques to stratify the risk for PE or DVT. However, higher sensitivities and negative predictive values were claimed in the scarce published reports for the D-Dimer PLUS assay than found in this study.     

Failure of computerized impedance plethysmography in the diagnostic management of patients with clinically suspected deep-vein thrombosis

Before a new diagnostic modality can be introduced in clinical medicine, the validity of both a normal and abnormal test result have to be assessed prospectively in an appropriate patient group. We have evaluated the clinical validity of a new computerized impedance plethysmography (CIP) in the diagnostic management of 381 consecutive patients with clinically suspected venous thrombosis. In patients with serially normal CIP results, the diagnosis of venous thrombosis was refuted and, consequently, they were not treated with anticoagulant therapy and all were followed up for a period of 6 months to estimate the occurrence of symptomatic venous thromboembolism. The study was prematurely terminated by the safety monitoring committee because of an unacceptably high incidence of confirmed venous thromboembolism (10 patients, 3.2%; 95% confidence interval: 1.6% to 6%), including 4 episodes of fatal pulmonary embolism. In a subsequent explanatory study using ultrasonography in 29 other symptomatic patients who had at least 2 repeated normal CIP test results, the failure of CIP to detect proximal vein thrombosis was confirmed in 4 patients (14%). The reasons for this failure are probably related to the use of a modified device to measure impedance in the CIP apparatus, resulting in a lower ability to separate patients without venous thrombosis from those with the disease. We concluded that CIP is insensitive for the detection of proximal vein thrombosis and, therefore, not clinically useful in the diagnostic management of patients with suspected venous thrombosis.     

Age- and sex-specific incidence, risk, and latency period of a perioperative acute thromboembolism syndrome (PATS)

We investigated age- and sex-specific incidence, risk factors, and latency period of a perioperative acute thromboembolism syndrome (PATS) in a large cohort study. We prospectively analyzed data on 21903 consecutive surgery patients to determine the incidence of myocardial infarction, pulmonary embolism, deep venous thrombosis, stroke, and cardiovascular death within 30 postoperative days. Among 255 (1.2 percent) patients with thromboembolism, 105 (0.48 percent) suffered myocardial infarction (mean latency: 5 days), 30 (0.14 percent) suffered pulmonary embolism (6 days), 23 (0.11 percent) suffered deep venous thrombosis (10 days), 97 (0.44 percent) suffered stroke (11 days), and 13 (0.06 percent) died (12 days).The critical period was postoperative week 1 for myocardial infarction and pulmonary embolism, and postoperative week 1 and 2 for deep venous thrombosis, stroke, and death. Risk of all events increased with age (P<0.0001), particularly for over 70 years (odds ratio: 12.5; 95 percent confidence interval, 7.8 to 19.9). Males had an increased risk (P<0.0001) of myocardial infarction (odds ratio; 1.5; 95 percent confidence interval, 1.0 to 2.3). Females had an increased risk (P<0.0001) of pulmonary embolism (odds ratio: 2.7; 95 percent confidence interval, 1.3 to 5.9) and deep venous thrombosis (odds ratio: 9.8; 95 percent confidence interval, 3.3 to 29.3). Risk of thromboembolic event was higher (P<0.0001) in patients with a history of arterial thrombotic events or cancer. Trend analysis indicates that thromboembolic events will increase 3-fold over the next decade. Our findings enable identification of higher risk patients for prophylactic anti-thromboembolic treatment and awareness of the critical postoperative period.     

Recurrent venous thromboembolism in a Spanish population: incidence, risk factors, and management in a hospital setting

The major concern in the management of venous thromboembolism is the propagation of thrombus and rethrombosis. The incidence of recurrences and the duration of oral anticoagulant therapy in these patients are still controversial. The aim of this study was to determine the incidence, timing, and outcome of further thrombotic events after an initial episode of venous thromboembolism in a hospital setting. In addition, we evaluated potential risk factors for all these outcomes. This was designed as a retrospective analysis of all patients admitted to our Center with an episode of deep vein thrombosis and/or pulmonary embolism between 1986 and 1996. The patients included in the study had to be treated with unfractionated heparin or low molecular weight heparin, followed by at least 3 months of oral anticoagulants. Natural and acquired hemostasis inhibitors were assayed in patients aged less than 50 years. A total of 290 patients with a first episode of venous thromboembolism were included in the study. A total of 33 patients (11.9%, 95% confidence interval. 7.4-14.6) had recurrent episodes. The cumulative incidence of recurrent venous thromboembolism after 2, 5, and 10 years was 7.68, 10, and 12.4%, respectively. The incidence of rethrombosis was significantly higher in patients with idiopathic venous thromboembolism than in patients with secondary thrombosis. Abnormalities of hemostasis were found in 54.5% (95% confidence interval, 37.6-71.4) of the patients with recurrences and under the age of 50 years. Three of seven patients who stopped anticoagulant therapy after the second episode presented a third thrombotic event. In our study population, those patients with idiopathic venous thromboembolism seem to have an increased risk of recurrence. The second thrombotic episode occurs more frequently during the following 2 years after cessation of anticoagulation therapy. Our findings strongly support the use of long-term anticoagulant therapy in patients with recurrent venous thromboembolism.     

Duration of oral anticoagulant treatment in patients with venous thromboembolism and a deficiency of antithrombin, protein C or protein S--a decision analysis

Patients with a first venous thromboembolic event and a deficiency of the coagulation inhibitors antithrombin, protein C or protein S have an increased risk of recurrent venous thromboembolism compared to patients without such a deficiency. A decision analysis was performed to assess the effect of continuing treatment with vitamin K antagonists on mortality by a reduction in fatal recurrent pulmonary embolism and an induction of fatal haemorrhages associated with their use. The treatment decision involves continuation or discontinuation of vitamin K antagonists in patients with a first spontaneous or secondary venous thromboembolism and an antithrombin, protein C or S deficiency. Although the efficiency of oral anticoagulation is high in all age groups early after the first thromboembolic event, it decreases over time. Our analysis indicates that the optimal treatment duration will vary, depending on the type of the initial event (spontaneous or secondary; deep venous thrombosis or pulmonary embolism), age, and time passed since the initial thromboembolic episode. Moreover, life-long duration of the prophylaxis seems not warranted in all patients.     

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。     

Venous thromboembolism in acute stroke. Prognostic importance of hypercoagulability.

To assess the incidence, risk factors, and clinical importance of deep vein thrombosis in acute stroke, we studied 70 consecutive patients who underwent hemostasis screening at the time of entry into the study and followed up these patients with serial venous Doppler examinations and the iodine 125-labeled fibrinogen uptake test. Mortality was significantly higher among the 20 patients who developed a deep vein thrombosis, and eight of them had necropsy evidence of pulmonary embolism. Severity of leg paresis and a shortened activated partial thromboplastin time were significantly associated with subsequent deep vein thrombosis with multivariate analysis. Significantly higher levels of fibrinopeptide A were found in patients with postmortem evidence of pulmonary embolism. Deep vein thrombosis is a frequent complication of acute stroke and may influence the prognosis by inducing pulmonary embolism. Our findings allow rapid identification of high-risk patients who may benefit maximally from prophylactic treatment of venous thromboembolism.     

Impaired fibrinolytic capacity predisposes for recurrence of venous thrombosis

The fibrinolytic capacity of 121 patients with a history of venous thrombosis and/or pulmonary embolism was studied by venous occlusion technique, at earliest 3 months after the last thromboembolic episode. After discontinuation of oral anticoagulation treatment the clinical course of the patients was followed and new thromboembolic episodes were noted. During the observation period of 56 +/- 18.8 months 45 of 121 patients experienced recurrence of thrombosis. The recurrence-rate was significantly lower in patients with a post-occlusion ELT shorter than 60 min (4.8%/year) than in patients with an ELT longer than 60 min (10.3%/year). It is concluded that the fibrinolytic capacity is a useful parameter for determining the risk of recurrence in patients with venous thrombosis.