Venous thromboembolism in patients hospitalized with nephrotic syndrome

Purpose

Whether pulmonary embolism in patients with the nephrotic syndrome is caused by deep venous thrombosis or renal vein thrombosis is controversial. To determine which is the likely cause of pulmonary embolism in patients with the nephrotic syndrome, we investigated data from the National Hospital Discharge Survey.

Methods

The number of patients discharged from nonfederal short-stay hospitals in the United States with a diagnostic code of nephrotic syndrome, deep venous thrombosis, renal vein thrombosis, and pulmonary embolism was obtained using ICD-9-M (International Classification of Diseases, Ninth Revision, Clinical Modification) codes.

Results

From 1979 to 2005, 925,000 patients were discharged from hospitals with the nephrotic syndrome and 898,253,000 patients did not have the nephrotic syndrome. With the nephrotic syndrome, 5000 (0.5%) had pulmonary embolism, 14,000 (1.5%) had deep venous thrombosis, and fewer than 5000 had renal vein thrombosis. The relative risk of pulmonary embolism comparing patients with the nephrotic syndrome to those who did not have it was 1.39, and the relative risk of deep venous thrombosis was 1.72. Among patients aged 18-39 years, the relative risk of deep venous thrombosis was 6.81. From 1991-2005, after venous ultrasound was generally available, the relative risk of deep venous thrombosis (all ages) was 1.77.

Conclusion

The nephrotic syndrome is a risk factor for venous thromboembolism. This is strikingly apparent in young adults. Renal vein thrombosis was uncommon. Therefore, pulmonary embolism, if it occurs, is likely to be due to deep venous thrombosis and not renal vein thrombosis.     

Prevention of central venous catheter-associated thrombosis: a meta-analysis

Purpose

Anticoagulant prophylaxis in patients with central venous catheters is controversial. We performed a meta-analysis of randomized controlled trials of anticoagulant prophylaxis in patients with central venous catheters.

Methods

MEDLINE and EMBASE were searched up to May 2006, supplemented by manual searches of conference proceedings and bibliographies.

Results

Fifteen trials were included. Unfractionated heparin infusion, oral fixed low-dose vitamin K antagonist, and subcutaneous low-molecular-weight heparin were evaluated. For all catheter-associated deep vein thrombosis (symptomatic and asymptomatic combined), the summary relative risks ranged from 0.31 to 0.73 (all achieved statistical significance). For symptomatic deep vein thrombosis, the summary relative risks ranged from 0.28 to 0.72, but did not achieve statistical significance for any individual regimen.

Conclusion

Anticoagulant prophylaxis is effective for preventing all catheter-associated deep vein thrombosis in patients with central venous catheters. The effectiveness for preventing symptomatic venous thromboembolism, including pulmonary embolism, remains uncertain.     

Incidence of venous thromboembolism in patients hospitalized with cancer

Background

There are sparse data on the frequency of venous thromboembolism in patients with various types of cancer. We sought to determine the incidence and relative risk of venous thromboembolism, pulmonary embolism, and deep venous thrombosis in patients with malignancies.

Subjects and methods

The number of patients discharged with a diagnostic code for 19 types of malignancies, pulmonary embolism or deep venous thrombosis from 1979 through 1999 was obtained from the National Hospital Discharge Survey. Patients studied were men and women of all ages and races.

Results

In patients with any of the 19 malignancies studied, 827 000 of 40 787 000 (2.0%) had venous thromboembolism, which was twice the incidence in patients without these malignancies, 6 854 000 of 662 309 000 (1.0 %). The highest incidence of venous thromboembolism was in patients with carcinoma of the pancreas, 51 000 of 1 176 000 (4.3%), and the lowest incidences were in patients with carcinoma of the bladder and carcinoma of the lip, oral cavity or pharynx. The overall incidences of pulmonary embolism and deep venous thrombosis were also twice the rates in noncancer patients. Incidences with cancer were not age dependent. The incidence of venous thromboembolism in patients with cancer began to increase in the late 1980s.

Conclusion

Patients with cancer had twice the incidence of venous thromboembolism, pulmonary embolism and deep venous thrombosis as patients without cancer. The incidence of venous thromboembolism, pulmonary embolism and deep venous thrombosis associated with cancer differed according to the type of cancer, was comparable in elderly and younger patients, and increased in the late 1980s and 1990s.     

Clinical characteristics of patients with acute pulmonary embolism: data from PIOPED II

Background

Selection of patients for diagnostic tests for acute pulmonary embolism requires recognition of the possibility of pulmonary embolism on the basis of the clinical characteristics. Patients in the Prospective Investigation of Pulmonary Embolism Diagnosis II had a broad spectrum of severity, which permits an evaluation of the subtle characteristics of mild pulmonary embolism and the characteristics of severe pulmonary embolism.

Methods

Data are from the national collaborative study, Prospective Investigation of Pulmonary Embolism Diagnosis II.

Results

There may be dyspnea only on exertion. The onset of dyspnea is usually, but not always, rapid. Orthopnea may occur. In patients with pulmonary embolism in the main or lobar pulmonary arteries, dyspnea or tachypnea occurred in 92%, but the largest pulmonary embolism was in the segmental pulmonary arteries in only 65%. In general, signs and symptoms were similar in elderly and younger patients, but dyspnea or tachypnea was less frequent in elderly patients with no previous cardiopulmonary disease. Dyspnea may be absent even in patients with circulatory collapse. Patients with a low-probability objective clinical assessment sometimes had pulmonary embolism, even in proximal vessels.

Conclusion

Symptoms may be mild, and generally recognized symptoms may be absent, particularly in patients with pulmonary embolism only in the segmental pulmonary branches, but they may be absent even with severe pulmonary embolism. A high or intermediate-probability objective clinical assessment suggests the need for diagnostic studies, but a low-probability objective clinical assessment does not exclude the diagnosis. Maintenance of a high level of suspicion is critical.     

Upper extremity deep vein thrombosis: a community-based perspective

Purpose

The purpose of this study was to examine the magnitude, risk factors, management strategies, and outcomes in a population-based investigation of patients with upper, as compared with lower, extremity deep vein thrombosis diagnosed in 1999.

Methods

The medical records of all residents from Worcester, Massachusetts (2000 census = 478,000) diagnosed with ICD-9 codes consistent with possible deep vein thrombosis at all Worcester hospitals during 1999 were reviewed and validated.

Results

The age-adjusted attack rate (per 100,000 population) of upper extremity deep vein thrombosis was 16 (95% confidence interval [CI], 13-20) compared with 91 (95% CI, 83-100) for lower extremity deep vein thrombosis. Patients with upper extremity deep vein thrombosis were significantly more likely to have undergone recent central line placement, a cardiac procedure, or an intensive care unit admission than patients with lower extremity deep vein thrombosis. Although short-term and 1-year recurrence rates of venous thromboembolism and all-cause mortality were not significantly different between patients with upper, versus lower, extremity deep vein thrombosis, patients with upper extremity deep vein thrombosis were less likely to have pulmonary embolism at presentation or in follow-up.

Conclusions

Patients with upper extremity deep vein thrombosis represent a clinically important patient population in the community setting. Risk factors, occurrence of pulmonary embolism, and timing and location of venous thromboembolism recurrence differ between patients with upper as compared with lower extremity deep vein thrombosis. These data suggest that strategies for prophylaxis and treatment of upper extremity deep vein thrombosis need further study and refinement.     

Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II investigators

Purpose

To formulate comprehensive recommendations for the diagnostic approach to patients with suspected pulmonary embolism, based on randomized trials.

Methods

Diagnostic management recommendations were formulated based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) and outcome studies.

Results

The PIOPED II investigators recommend stratification of all patients with suspected pulmonary embolism according to an objective clinical probability assessment. D-dimer should be measured by the quantitative rapid enzyme-linked immunosorbent assay (ELISA), and the combination of a negative D-dimer with a low or moderate clinical probability can safely exclude pulmonary embolism in many patients. If pulmonary embolism is not excluded, contrast-enhanced computed tomographic pulmonary angiography (CT angiography) in combination with venous phase imaging (CT venography), is recommended by most PIOPED II investigators, although CT angiography plus clinical assessment is an option. In pregnant women, ventilation/perfusion scans are recommended by many as the first imaging test following D-dimer and perhaps venous ultrasound. In patients with discordant findings of clinical assessment and CT angiograms or CT angiogram/CT venogram, further evaluation may be necessary.

Conclusion

The sequence for diagnostic test in patients with suspected pulmonary embolism depends on the clinical circumstances.     

Incidence and risk factors of venous thromboembolic events in lymphoma

Background

Cancer patients are at increased risk of venous thromboembolism; however, the incidence and risk factors for venous thromboembolism in lymphoma patients are not well defined.

Methods

Medical records of 422 newly referred lymphoma patients at our institution were reviewed over 2-year follow-up for all venous thromboembolism events and potential risk factors. Multivariate logistic regression model was used to identify risk factors predictive of venous thromboembolism.

Results

Among 422 patients, 72 (17.1 %) had 80 new episodes of venous thromboembolism: 59 had deep vein thrombosis, 17 had pulmonary embolism, and 4 had combined deep vein thrombosis and pulmonary embolism. Only 18 of 422 patients (4.3%) were on thromboprophylaxis at baseline. Interestingly, 64% (51/80) of the episodes occurred by the third cycle of chemotherapy. By multivariate logistic regression, female sex (odds ratio [OR] 3.51, P = .001), high hemoglobin (OR 1.26, P = .020), high serum creatinine (OR 3.23, P = .009), and doxorubicin- or methotrexate-based chemotherapy (OR 3.47, P = 0.003) were important risk factors for new venous thromboembolism.

Conclusions

Lymphoma patients are at high risk for venous thromboembolism in the initial cycles of chemotherapy; the risk was higher for women, patients with elevated hemoglobin or creatinine, or those receiving doxorubicin or methotrexate. Future studies might focus on validation of these risk factors to identify the high-risk cohort and the potential role of thromboprophylaxis, particularly during initial cycles of chemotherapy.     

Clinical usefulness and prognostic value of elevated cardiac troponin I levels in acute pulmonary embolism

Background

Right ventricular myocardial ischemia and injury contribute to right ventricular dysfunction and failure during acute pulmonary embolism. The objective of this study was to evaluate the clinical usefulness of cardiac troponin I (cTnI) in the assessment of right ventricular involvement and short-term prognosis in acute pulmonary embolism

Methods

Thirty-eight patients with acute pulmonary embolism were included in the study. Clinical characteristics, right ventricular involvement, and clinical outcome were compared in patients with elevated levels of serum cTnI versus patients with normal levels of serum cTnI.

Results

Among the study population (n = 38 patients), 18 patients (47%) had elevated cTnI levels (mean ± SD 1.6 ± 0.7 ng/mL, range 0.7-3.7 ng/mL, median, 1.4 ng/mL), and comprised the cTnI-positive group. In the other 20 patients, the serum cTnI levels were normal (≤0.4 ng/mL), and they comprised the cTnI-negative group. In the cTnI-positive group (n = 18 patients), 12 patients (67%) had right ventricular dilatation/hypokinesia, compared with 3 patients (15%) in the cTnI-negative group (n = 20 patients, P = .004). Right ventricular systolic pressure was significantly higher in the cTnI-positive group (51 ± 8 mm Hg vs 40 ± 9 mm Hg, P = .002). Cardiogenic shock developed in a significantly higher number of patients with elevated serum cTnI levels (33% vs 5%, P = .01). In patients with elevated cTnI levels, the odds ratio for development of cardiogenic shock was 8.8 (95% CI 2.5-21).

Conclusions

Patients with acute pulmonary embolism with elevated serum cTnI levels are at a higher risk for the development of right ventricular dysfunction and cardiogenic shock. Serum cTnI has a role in risk stratification and short-term prognostication in patients with acute pulmonary embolism.     

Deep venous thrombosis and pulmonary embolism in hospitalized patients with sickle cell disease

Background

As would be expected with a hypercoagulable state, pulmonary embolism (PE) occurs in sickle cell disease (SCD). Its frequency, however, is undetermined, largely because of difficulties in distinguishing it from thrombosis in situ. The prevalence of deep venous thrombosis (DVT) is also undetermined in patients with SCD. Knowing the prevalence of DVT would be an important step in the overall assessment of the risk of PE in these patients.

Methods

Data from the National Hospital Discharge Survey were assessed.

Results

In patients <age 40 years, 7000 of 1,581,000 (0.44%) with SCD had a discharge diagnosis of PE compared with 59,000 of 48,611,000 (0.12%) of African Americans without SCD. The prevalence of DVT was similar in patients < age 40 with SCD, 7000 of 1,581,000 (0.44%) and in African Americans who did not have SCD, 193,000 of 48,611,000 (0.40%).

Conclusion

The high prevalence of apparent PE in patients with SCD, compared with non-SCD African-American patients of the same age and the comparable prevalence of DVT in both groups are compatible with the concept that thrombosis in situ might be present in many. On the other hand, the data suggest that PE is not rare in patients with SCD. This suggests that PE might be an etiologic factor in patients with SCD who develop respiratory symptoms. In such patients, an imaging procedure might be appropriate.     

Outcomes for Inpatients with Normal Findings on Whole-leg Ultrasonography: A Prospective Study

Background

Ultrasonography is used routinely for ruling out suspected deep vein thrombosis in hospitalized patients, although most evidence supporting this strategy is derived from the outpatient setting. This study aimed to estimate the rate of venous thromboembolism when anticoagulant therapy was withheld from inpatients with normal findings on whole-leg ultrasonography.

Methods

As part of a prospective multicenter cohort study, 1926 medical and surgical inpatients with clinically suspected deep vein thrombosis during their stay were enrolled. Ultrasonography of all lower extremities was performed by board-certified vascular medicine physicians using a standardized examination protocol. Deep vein thrombosis was detected in 395 patients (20%). Anticoagulant therapy was withheld from patients with normal findings, and 523 of them were randomly selected for follow-up. The main outcome measure was 3-month incidence of symptomatic venous thromboembolism.

Results

A total of 513 patients with normal findings on ultrasonography successfully completed 3 months of follow-up, 9 patients were lost to follow-up, and 1 patient received anticoagulant therapy during follow-up. Three patients (0.6%) experienced nonfatal symptomatic venous thromboembolic events confirmed by objective testing. The cause of death was judged to be possibly related to pulmonary embolism for 7 other patients (1.3%). Overall, the 3-month rate of venous thromboembolism was 1.9% (10/513; 95% confidence interval, 0.9-3.5).

Conclusion

Although withholding anticoagulant therapy after a single negative whole-leg ultrasonography seems to be safe, up to 3.5% of inpatients may nevertheless develop venous thromboembolism in the next 3 months. Further study is warranted to determine whether this strategy is equivalent to serial compression ultrasonography limited to proximal veins.     

Venous Compression for Prevention of Postthrombotic Syndrome: A Meta-analysis

Purpose

To determine the effectiveness of venous compression stockings or compression bandages on the reduction of postthrombotic syndrome in patients with deep venous thrombosis.

Methods

We attempted to identify all published trials in all languages identified by PubMed through June 2009. Meta-analysis was performed.

Results

Based on 5 randomized trials of patients with deep venous thrombosis comparing treatment with venous compression to controls, mild-to-moderate postthrombotic syndrome occurred in 64 of 296 (22%) treated with venous compression, compared with 106 of 284 (37%) in controls (relative risk = 0.52). Severe postthrombotic syndrome occurred in 14 of 296 (5%) treated, compared with 33 of 284 (12%) controls (relative risk = 0.38). Any postthrombotic syndrome occurred in 89 of 338 (26%) treated, compared with 150 of 324 (46%) controls (relative risk = 0.54).

Conclusion

Venous compression reduced the incidence of postthrombotic syndrome, particularly severe postthrombotic syndrome. Venous compression in patients with deep venous thrombosis would seem to be indicated for this purpose. There was, however, wide variation in the type of stockings used, time interval from diagnosis to application of stockings, and duration of treatment. Further investigation, therefore, is needed.     

Risk of venous thromboembolism in first- and second-generation immigrants in Sweden

Background

There are ethnic differences in the incidence of venous thromboembolism. This is the first nationwide study to examine whether there is an association between country of birth in first-generation immigrants and first hospitalisation for venous thrombosis (VT) and pulmonary embolism (PE), and to study whether a similar association exists in second-generation immigrants.

Methods

The study is a nationwide follow-up study. The study subjects were first- and second-generation immigrants residing in Sweden between January 1, 1964 and December 31, 2007. The reference population comprised first- and second-generation Swedish-born individuals. Standardised incidence ratios (SIRs) for VT and PE, standardised with regard to age, geographic region of residence, time period, and socioeconomic status, were estimated by sex in first- and second-generation immigrants.

Results

First-generation male and/or female immigrants from Greece, Italy, Spain, Finland, Baltic countries, Central Europe, Eastern Europe, Russia, Latin America, Turkey, Iran, and Iraq had a lower risk of VT and/or PE than Swedish-born individuals. The lower risk of VT and/or PE in some first-generation immigrant groups was not replicated in the second generation. However, in certain second-generation immigrant groups, the risk of VT/PE was similar to that in the corresponding parental groups.

Conclusions

Country of birth affects the risk of VT and PE in several immigrant groups. Our study indicates that ethnicity-related inherited and acquired venous thromboembolism risk factors play a role in the aetiology of venous thromboembolism. Ethnic differences in thromboembolism risk even exist in Caucasian European populations, and may thus be important to consider in genetic studies.     

The prophylaxis of medical patients for thromboembolism pilot study

Purpose

We assessed the feasibility of a large randomized trial intended to determine whether low-dose heparin prophylaxis given throughout hospitalization reduces mortality and morbidity in general medical patients.

Subjects and methods

Hospitalized general medical patients aged more than 60 years at 5 Department of Veterans Affairs (VA) medical centers were randomized to receive enoxaparin 40 mg or identical placebo, given daily by subcutaneous injection until hospital discharge. Outcomes included total mortality at 90 days (the primary outcome) and 1 year, and occurrence in the VA hospital within 90 days of symptomatic deep venous thrombosis, pulmonary embolism, and major bleeding.

Results

Only 7.6% of hospitalized patients aged more than 60 years were eligible for the study, although a chart review had predicted 25%. The principal exclusions were prior indication for anticoagulation, anticipated need for anticoagulation, contraindication to heparin, expected hospitalization less than 3 days, and “supportive/palliative care only” status. We randomized 140 patients into each group, 28% of target recruitment. The groups were well matched by age and comorbidities. Death occurred in 13 patients receiving enoxaparin and 14 patients receiving placebo at 90 days (relative risk 0.93, 95% confidence interval 0.26-1.59), and in 36 and 32 patients, respectively, at 1 year (relative risk 1.13, 95% confidence interval 0.66-1.60). Clinical thromboembolic events occurred in 5 patients receiving enoxaparin and 8 patients receiving placebo, and major bleeding occurred in 2 and 5 patients, respectively.

Conclusions

The pilot study indicated that the full study was not feasible. The decision to use prophylaxis pertains to only a small proportion of general medical patients hospitalized at VA medical centers, and this proportion is overestimated by chart review. The effect of low-dose heparin prophylaxis on clinical outcomes in hospitalized general medical patients remains uncertain.     

In-Hospital Mortality with Deep Venous Thrombosis

Background

Little is known about the in-hospital mortality of deep venous thrombosis in recent years. This investigation was undertaken to determine trends in in-hospital mortality in patients with deep venous thrombosis and mortality according to age.

Removal of retrievable vena cava filters in routine practice: a multicenter study

Vena cava filters (VCFs) are used to prevent pulmonary embolism when anticoagulation is contraindicated or in the event of progression of thrombosis despite adequate anticoagulation. Retrievable VCFs provide a potential advantage over permanent VCFs, but the appropriateness of their use and the frequency with which they are removed is not well established.

Objectives

Document the indications for insertion of retrievable VCFs, filter removal in hospital practice.

Methods

Observational study conducted in three academic medical centers. Consecutive patients undergoing retrievable VCF insertion were identified. Clinical data was extracted from the patients' charts and follow up data were obtained from treating physicians after discharge.

Results

300 patients were studied. The indication for filter insertion was acute bleeding (46.1%) or surgery (24.2%) in patients with acute thrombosis, prevention of venous thromboembolism in trauma (13.3%), potential bleeding in patients with deep vein thrombosis (9.1%) thromboembolism while on adequate anticoagulation (5.7%) and other (1.3%).21 (7%) filters were removed. An unsuccessful attempt at retrieval was undertaken in a further 9 (3%) patients.

Conclusions

The use of retrievable VCFs was appropriate, with the possible exception of their prophylactic use in major trauma. The majority of VCFs were not removed, for reasons that are not apparent.     

Home Therapy of Venous Thrombosis with Long-term LMWH versus Usual Care: Patient Satisfaction and Post-thrombotic Syndrome

Purpose

Home-LITE compared long-term treatment at home with tinzaparin or usual care in terms of efficacy, safety, patients' treatment satisfaction, incidence of post-thrombotic syndrome, and associated venous leg ulcers.

Methods

This multicenter, randomized, controlled trial enrolled 480 patients with documented, acute, proximal deep vein thrombosis. Patients received tinzaparin 175 IU/kg subcutaneously once daily for 12 weeks, or tinzaparin for ≥5 days plus oral warfarin, commenced on day 1, international normalized ratio-adjusted, and continued for ≥12 weeks (“usual care”). Patients received 1 in-clinic injection, then home treatment.

Results

The rate of recurrent venous thromboembolism at 12 weeks was 3.3% in both groups (absolute difference 0%; 95% confidence interval −3.2-3.2), and at 1 year was 10.4%/8.3% in the tinzaparin/usual-care groups, respectively (difference 2.1%; 95% confidence interval −3.1-7.3). There were no between-group differences in deaths at 12 weeks or 1 year, or bleeding at 12 weeks. Patients in the tinzaparin group expressed significantly greater treatment satisfaction (P = .0024), particularly regarding freedom from the inconvenience of blood monitoring; were less likely to report signs/symptoms of post-thrombotic syndrome (individual odds ratios 0.66 to 0.91, overall odds ratio 0.77, P = .001); and reported fewer leg ulcers at 12 weeks: 1 (0.5%) versus 8 (4.1%) (P = .02) with usual care.

Conclusions

Long-term home treatment with tinzaparin or usual care resulted in similar rates of recurrent venous thromboembolism, death, and bleeding. The significantly lower incidence of post-thrombotic syndrome and leg ulcers observed in the tinzaparin group is a potentially important benefit and deserves further study.     

Incidence of and Mortality from Venous Thromboembolism in a Real-world Population: The Q-VTE Study Cohort

Background

The public health burden of venous thromboembolism, which includes deep vein thrombosis and pulmonary embolism, is not fully known, and contemporary incidence and mortality estimates are needed. We determined the incidence and case fatality of venous thromboembolism in a general population.

Methods

Using the administrative health care databases of the Canadian province of Québec, we identified all incident cases of deep vein thrombosis or pulmonary embolism between 2000 and 2009 and classified them as definite or probable venous thromboembolism. We formed 2 patient cohorts, one with definite cases and the other including cases with definite or probable venous thromboembolism that were followed until December 31, 2009.

Results

We identified 67,354 definite and 35,123 probable cases of venous thromboembolism. The age- and sex-adjusted incidence rates of definite or probable venous thromboembolism, deep vein thrombosis, and pulmonary embolism were 1.22 (95% confidence interval [CI], 1.22-1.23), 0.78 (95% CI, 0.77-0.79), and 0.45 (95% CI, 0.44-0.45) per 1000 person-years, respectively, while for definite venous thromboembolism it was 0.90 (95% CI, 0.89-0.90) per 1000 person-years. The 30-day and 1-year case-fatality rates after definite or probable venous thromboembolism were 10.6% (95% CI, 10.4-10.8) and 23.0% (95% CI, 22.8-23.3), respectively, and were slightly higher among definite cases. The 1-year survival rate was 0.47 (95% CI, 0.46-0.48) for cases with definite or probable venous thromboembolism and cancer, 0.93 (95% CI, 0.93-0.94) for cases with unprovoked venous thromboembolism, and 0.84 (95% CI, 0.83-0.84) for cases with venous thromboembolism secondary to a major risk factor. Similar survival rates were seen for cases with definite venous thromboembolism.

Conclusion

The risk of venous thromboembolism in the general population remains high, and mortality, especially in cancer patients with venous thromboembolism, is substantial.     

Increasing use of vena cava filters for prevention of pulmonary embolism

Purpose

To test whether the use of vena cava filters continues to increase in the era of retrievable filters, suggesting that indications for insertion are broadening.

Methods

Data from 1979 through 2006 are from the National Hospital Discharge Survey.

Results

From 1979 through 1984, 17,000 vena cava filters were inserted; 8000 in patients with pulmonary embolism, 4000 in patients with deep venous thrombosis only, and 5000 in patients at risk of pulmonary embolism who had neither. From 1985 through 2006, 803,000 vena cava filters were inserted: 285,000 in patients with pulmonary embolism, 360,000 in patients with deep venous thrombosis only, and 158,000 in patients who had neither. The largest proportional increases in the use of vena cava filters since the introduction of retrievable filters was in patients at risk of pulmonary embolism but who had neither pulmonary embolism nor deep venous thrombosis. The trend toward increased use in this group began before retrievable filters were introduced. There was a 3-fold increase from 2001-2006.

Conclusion

Extensive use of permanent and retrievable vena cava filters in the US indicates liberalization of indications. It would seem that a more discriminate use of vena cava filters would be appropriate at the present time, keeping an open mind for broadened indications as data accrue.     

Predictors and Outcomes of Recurrent Venous Thromboembolism in Elderly Patients

Background

Little is known about predictors and outcomes of recurrent venous thromboembolism in elderly patients.

Self-managed long-term low-molecular-weight heparin therapy: the balance of benefits and harms

Purpose

A substantial clinical need exists for an alternate to vitamin K antagonists for treating deep vein thrombosis in many patients. Long-term low-molecular-weight heparin (LMWH), body-weight adjusted, avoids anticoagulant monitoring and may be associated with less bleeding. We evaluated the effectiveness and safety of long-term LMWH compared with vitamin K antagonist therapy in a broad spectrum of patients with proximal vein thrombosis.

Methods

We performed a multicenter, randomized, open-label clinical trial using objective outcome measures comparing therapy for 3 months. Outcomes were assessed at 3 and 12 months.

Results

Of 737 patients, 18 of 369 receiving tinzaparin (4.9%) had recurrent venous thromboembolism at 3 months compared with 21 of 368 (5.7%) receiving usual care (absolute difference, −0.8%, 95% confidence interval −4.1-2.4). Hemorrhagic complications occurred less frequently in the LMWH group largely because of less minor bleeding: 48 of 369 patients (13.0%) versus 73 of 368 patients (19.8%) receiving usual-care anticoagulation (absolute difference −6.8%; P = .011; risk ratio = 0.66). New major bleeding events ceased early (by day 23, P = .034) for patients receiving LMWH but persisted throughout the study treatment interval for patients receiving vitamin K antagonist therapy. No mortality advantage was shown for LMWH.

Conclusion

Our study shows that LMWH is similar in effectiveness to the usual-care vitamin K antagonist treatment for preventing recurrent venous thromboembolism in a broad spectrum of patients. It causes less harm and enhances the clinicians’ therapeutic options for patients with proximal deep vein thrombosis. Our findings reported here suggest the possibility of a broader role for long-term LMWH in selected patients.