In this trial, administering aspirin before surgery and during the early postsurgical period did not affect the rate of death or nonfatal MI but increased the risk of major bleeding. This was true in ...patients who had not been taking aspirin and in those on a long-term aspirin regimen.
Myocardial infarction is the most common major vascular complication that occurs after noncardiac surgery.
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Noncardiac surgery is associated with platelet activation,
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and coronary-artery thrombus may be a mechanism of perioperative myocardial infarction.
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Aspirin inhibits platelet aggregation,
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and the perioperative administration of aspirin may prevent major vascular complications by inhibiting thrombus formation.
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In a meta-analysis of data from large, randomized trials involving more than 110,000 patients who were not undergoing surgery, the use of aspirin was shown to prevent myocardial infarction and major vascular events.
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High-dose aspirin has not been shown to be superior to low-dose aspirin in preventing . . .
Laboratory evidence of antiphospholipid antibodies (APLA) in patients with a first episode of venous thromboembolism (VTE) is often considered an indication for indefinite anticoagulant therapy, but ...it is uncertain if this practice is justified. We performed a systematic review to determine whether the presence of APLA in patients with a first VTE is associated with an increased risk of recurrence. We searched PubMed, CINAHL, Cochrane, EMBASE, and Web of Knowledge through February 2012 and included prospective studies that met prespecified design criteria. There were 109 recurrent VTE in 588 patients with APLA and 374 recurrent VTE in 1914 patients without APLA (relative risk 1.41; 95% confidence interval CI, 0.99 to 2.36). The unadjusted risk ratio for recurrent VTE after stopping anticoagulant therapy in patients with an anticardiolipin antibody was 1.53 (95% CI, 0.76-3.11), and with a lupus anticoagulant was 2.83 (95% CI, 0.83-9.64). All studies had important methodologic limitations and we judged the overall quality of the evidence as very low. Although a positive APLA test appears to predict an increased risk of recurrence in patients with a first VTE, the strength of this association is uncertain because the available evidence is of very low quality.
•The quality of evidence pertaining to the risk of recurrent thrombosis among patients with an antiphospholipid antibody is very low.•Additional studies are needed to define the impact of APLA testing on clinical decision-making.
Summary Background Post-thrombotic syndrome (PTS) is a common and burdensome complication of deep venous thrombosis (DVT). Previous trials suggesting benefit of elastic compression stockings (ECS) to ...prevent PTS were small, single-centre studies without placebo control. We aimed to assess the efficacy of ECS, compared with placebo stockings, for the prevention of PTS. Methods We did a multicentre randomised placebo-controlled trial of active versus placebo ECS used for 2 years to prevent PTS after a first proximal DVT in centres in Canada and the USA. Patients were randomly assigned to study groups with a web-based randomisation system. Patients presenting with a first symptomatic, proximal DVT were potentially eligible to participate. They were excluded if the use of compression stockings was contraindicated, they had an expected lifespan of less than 6 months, geographical inaccessibility precluded return for follow-up visits, they were unable to apply stockings, or they received thrombolytic therapy for the initial treatment of acute DVT. The primary outcome was PTS diagnosed at 6 months or later using Ginsberg's criteria (leg pain and swelling of ≥1 month duration). We used a modified intention to treat Cox regression analysis, supplemented by a prespecified per-protocol analysis of patients who reported frequent use of their allocated treatment. This study is registered with ClinicalTrials.gov , number NCT00143598 , and Current Controlled Trials, number ISRCTN71334751. Findings From 2004 to 2010, 410 patients were randomly assigned to receive active ECS and 396 placebo ECS. The cumulative incidence of PTS was 14·2% in active ECS versus 12·7% in placebo ECS (hazard ratio adjusted for centre 1·13, 95% CI 0·73–1·76; p=0·58). Results were similar in a prespecified per-protocol analysis of patients who reported frequent use of stockings. Interpretation ECS did not prevent PTS after a first proximal DVT, hence our findings do not support routine wearing of ECS after DVT. Funding Canadian Institutes of Health Research.
Background & Aims Guidelines for the management of venous thromboembolism (VTE) from the American College of Chest Physicians do not address patients with inflammatory bowel disease (IBD), a group ...with a high risk of both VTE and gastrointestinal bleeding. We present recommendations for the prevention and treatment of VTE in patients with IBD. Methods A systematic literature search was performed to identify studies on VTE in IBD. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Statements were developed through an iterative online platform, then finalized and voted on by a working group of adult and pediatric gastroenterologists and thrombosis specialists. Results IBD patients have an approximately 3-fold higher risk of VTE compared with individuals without IBD, and disease flares further increase this risk. Anticoagulant thromboprophylaxis is recommended for IBD patients who are hospitalized with IBD flares without active bleeding and is suggested when bleeding is nonsevere. Anticoagulant thromboprophylaxis is suggested during moderate−severe IBD flares in outpatients with a history of VTE provoked by an IBD flare or an unprovoked VTE, but not otherwise. The recommended duration of anticoagulation after a first VTE is based on the presence of provoking factors. Specific suggestions are made for the prevention and treatment of VTE in pediatric and pregnant IBD patients. Conclusions Using the American College of Chest Physicians’ guidelines as a foundation, we have integrated evidence from IBD studies to develop specific recommendations for the management of VTE in this high-risk population.
Venous thromboembolism (VTE) prophylaxis is indicated while in the hospital after major surgery. There is evidence that the prevalence of asymptomatic deep-vein thrombosis, detected by routine ...venography after major orthopedic surgery, is lower at hospital discharge in patients who have received 10 days rather than 5 days of prophylaxis. This observation supports the current American College of Chest Physicians (ACCP) recommendation for a minimum of 7 to 10 days of prophylaxis after hip and knee replacement, even if patients are discharged from the hospital within 7 days of surgery. As risk of VTE persists for up to 3 months after surgery, patients at high risk for postoperative VTE may benefit from extended prophylaxis (eg, an additional 3 weeks after the first 7 to 10 days). Extended prophylaxis with low-molecular-weight heparin (LMWH) reduces the frequency of postdischarge VTE by approximately two thirds after hip replacement; however, the resultant absolute reduction in the frequency of fatal pulmonary embolism is small (ie, estimated at 1 per 2,500 patients). Indirect evidence suggests that, compared with LMWH, efficacy of extended prophylaxis after hip replacement is greater with fondaparinux, similar with warfarin, and less with aspirin. Extended prophylaxis is expected to be of less benefit after knee than after hip replacement. In keeping with current ACCP recommendations, at a minimum, extended prophylaxis should be used after major orthopedic surgery in patients who have additional risk factors for VTE (eg, previous VTE, cancer). If anticoagulant drug therapy is stopped after 7 to 10 days, an additional month of prophylaxis with aspirin should be considered.
Individual risk of recurrent venous thromboembolism affects patient management and might differ between men and women. We did a meta-analysis to assess from available evidence whether men and women ...have the same risk of recurrent venous thromboembolism after stopping anticoagulant treatment.
Eligible articles were identified by searches of MEDLINE (source PubMed, 1966 to February 2005), EMBase (1980 to February 2005), and the Cochrane database 2005, issue 1. Prospective cohort studies and randomised trials were eligible if they included patients with objectively diagnosed venous thromboembolism treated for a minimum of 1 month and followed up for recurrence after anticoagulant treatment was stopped. Data were extracted for study design, study quality, and the number, sex, and age of enrolled patients, risk factors for venous thromboembolism, treatment given, duration of follow-up, and the number of episodes of recurrent venous thrombosis.
15 studies (nine randomised controlled trials and six prospective observational studies) enrolling a total of 5416 individuals (2729 men), of whom 816 (523 men) had recurrent venous thromboembolism after stopping treatment, were eligible for inclusion. The pooled estimate of the relative risk (RR) of recurrent venous thromboembolism for men compared with for women was 1·6 (95% CI 1·2–2·0). Significant heterogeneity was shown among individual study findings; however, the higher risk of recurrent venous thromboembolism in men than in women was consistent across predefined subgroups. The relative risk for recurrence in men from randomised trials (RR 1·3; 95% CI 1·0–1·8) was lower than that from observational studies (2·1; 1·5–2·9). The lower risk of recurrent venous thromboembolism in women did not seem to be accounted for by a reduced rate of recurrence after venous thromboembolism associated with oestrogen treatment or pregnancy.
Men seem to have a 50% higher risk than women of recurrent venous thromboembolism after stopping anticoagulant treatment. If confirmed by further prospective studies, this difference in risk of recurrence should be considered when duration of anticoagulant treatment is determined in individual patients.
The diagnosis of deep-vein thrombosis is based on clinical evaluation of the patient and ultrasound examination of the lower extremities. This study found that measurement of D-dimer reduced the need ...for ultrasound examination without compromising patient safety.
Measurement of D-dimer reduced the need for ultrasound examination.
Suspected deep-vein thrombosis is a common condition, with a lifetime cumulative incidence of 2 to 5 percent. Untreated deep-vein thrombosis can result in pulmonary embolism, a potentially fatal outcome. Anticoagulant therapy reduces both morbidity and mortality from venous thromboembolism, and early diagnosis is therefore important. Accurate diagnosis of deep-vein thrombosis minimizes the risk of thromboembolic complications and averts the exposure of patients without thrombosis to the risks of anticoagulant therapy.
We previously determined that the use of a clinical model allows physicians to categorize accurately the probability that a patient has deep-vein thrombosis before tests are performed.
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Subsequently, analysis of . . .
Background Current standard therapy for patients with acute proximal deep vein thrombosis (DVT) consists of anticoagulant therapy and graduated elastic compression stockings. Despite use of this ...strategy, the postthrombotic syndrome (PTS) develops frequently, causes substantial patient disability, and impairs quality of life. Pharmacomechanical catheter-directed thrombolysis (PCDT), which rapidly removes acute venous thrombus, may reduce the frequency of PTS. However, this hypothesis has not been tested in a large multicenter randomized trial. Study design The ATTRACT Study is an ongoing National Institutes of Health–sponsored, Phase III, multicenter, randomized, open-label, assessor-blinded, parallel two-arm, controlled clinical trial. Approximately 692 patients with acute proximal DVT involving the femoral, common femoral, and/or iliac vein are being randomized to receive PCDT + standard therapy versus standard therapy alone. The primary study hypothesis is that PCDT will reduce the proportion of patients who develop PTS within 2 years by one-third, assessed using the Villalta Scale. Secondary outcomes include safety, general and venous disease-specific quality of life, relief of early pain and swelling, and cost-effectiveness. Conclusion ATTRACT will determine if PCDT should be routinely used to prevent PTS in patients with symptomatic proximal DVT above the popliteal vein.
This chapter about hemorrhagic complications of anticoagulant treatment is part of the seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy: Evidence Based Guidelines. Bleeding is the ...major complication of anticoagulant therapy. The criteria for defining the severity of bleeding varies considerably between studies, accounting in part for the variation in the rates of bleeding reported. The major determinants of vitamin K antagonist-induced bleeding are the intensity of the anticoagulant effect, underlying patient characteristics, and the length of therapy. There is good evidence that vitamin K antagonist therapy, targeted international normalized ratio (INR) of 2.5 (range, 2.0 to 3.0), is associated with a lower risk of bleeding than therapy targeted at an INR > 3.0. The risk of bleeding associated with IV unfractionated heparin (UFH) in patients with acute venous thromboembolism (VTE) is < 3% in recent trials. This bleeding risk may increase with increasing heparin dosages and age (> 70 years). Low molecular weight heparin (LMWH) is associated with less major bleeding compared with UFH in acute VTE. UFH and LMWH are not associated with an increase in major bleeding in ischemic coronary syndromes, but are associated with an increase in major bleeding in ischemic stroke. Information on bleeding associated with the newer generation of antithrombotic agents has begun to emerge. In terms of treatment decision making for anticoagulant therapy, bleeding risk cannot be considered alone, ie, the potential decrease in thromboembolism must be balanced against the potential increased bleeding risk.
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