Disease burden and unmet needs for prevention of venous thromboembolism in medically ill patients in Europe show underutilisation of preventive therapies

Venous Thromboembolism Prophylaxis in Medical and Surgical Patients - What's Our Reality?

INTRODUCTION

Venous thromboembolism (VTE) includes pulmonary embolism (PE), deep vein thrombosis (DVT) in lower limbs, and thrombosis in rare locations. VTE is a common cardiovascular disease, being the leading preventable cause of in-hospital death. Both surgical and acute medical patients have an elevated risk of developing VTE. VTE risk assessment is essential to identify patients who might benefit from VTE prophylaxis accurately. Clinical data on risk factors and prophylaxis in Portugal are scarce. We aimed to determine the proportion of at-risk patients who received prophylaxis and the incidence of bleeding events. We also intended to study the rate of VTE in a cohort of medical and surgical patients during the hospitalization period and three months after discharge.

METHODS

During one week in 2020, adults admitted for more than 72hr to a medical or surgical ward were included. The study excluded patients with a diagnosis of VTE three months before hospitalization and who were either chronically receiving anticoagulation therapy or had started it 48 hours after admission. Risk assessments were based on the Padua Prediction Score (PPS) for medical patients and the Caprini Risk Assessment Model (CRAM) for surgical patients. We used CHEST guidelines, 9th edition, to determine the adequacy of the prophylactic method.

RESULTS

A total of 123 patients were analyzed, 18.7% of which tested positive for SARS-CoV-2. VTE risk in surgical patients was categorized as very low or low (16.6%), moderate (37.5%), and high (43.8%), according to the CRAM. Risk in medical patients was categorized as low (60.0%) or high (40.0%) according to the PPS. We estimated that VTE chemoprophylaxis was overused in about 30.0% of patients vs. 7.0% who were at risk and did not receive appropriate chemoprophylaxis. The rate of thromboembolic events was 4.1% (n=5), 2 of which happened after discharge. Two of these patients were under VTE prophylaxis during hospitalization. Major bleeding occurred in 2.4% of patients (n=3).

DISCUSSION

A significant number of hospitalized patients are deemed to be at risk for VTE, making appropriate prophylaxis essential. The results emphasize the insufficient management of VTE prophylaxis.

A review of venous thromboembolism risk assessment models for different patient populations: What we know and don't!

Venous thromboembolism (VTE) is a common cause of morbidity and mortality in hospitalized patients. Globally, it is also the third leading vascular disease, after myocardial infarction and stroke. The incidence of VTE is reportedly higher in Western countries than in Asian countries. However, recent reports suggest an increasing incidence of VTE in Asian countries, including India. Since VTE is largely a preventable disease, early identification of risk factors can lead to disease prevention or the adoption of appropriate prophylactic measures. To this end, several VTE risk assessment models (RAMs) have been developed and validated for different populations who are at risk of developing VTE, such as hospitalized patients with medical illness/surgical indication, patients with cancer, and pregnant women. Evidence indicates that the systematic use of RAMs improves prophylaxis rates and lowers the burden of VTE. Given the increasing burden of VTE in the Indian population and poor prophylaxis rates, the implementation of systematic RAMs in routine clinical practice might ameliorate the disease burden in the country. We have assessed the evidence-based utilities of available RAMs and have delineated the most common and suitable RAMs for different populations including coronavirus disease 2019 affected patients. This review depicts the current status of implementation and validation of RAMs in the Indian scenario. It also highlights the need for additional validation studies, improved awareness, and implementation of RAMs in clinical practice for lowering the burden of VTE.

Venous Thromboembolism Among Hospitalized Patients: Incidence and Adequacy of Thromboprophylaxis - A Retrospective Study

Purpose

We aimed to determine the incidence of venous thromboembolism among hospitalized patients in Qatar as well as to analyze the adequacy of VTE assessment and prophylaxis in hospitalized patients.

Design

Retrospective observational study.

Setting

Four hospitals under Hamad Medical Corporation, Qatar.

Participants

Patients over the age of 18 who were hospitalized between January 2015 and December 2019 and developed venous thromboembolism during hospitalization or within a month after discharge were included.

Results

During the study period, 641,994 individuals were admitted to hospitals. The inclusion criteria were satisfied by 209 of them. The mean age was 51.25 years and 54.5% were males. Hypertension and diabetes mellitus were the most common comorbidities found in the overall group. The incidence of VTE was 32.55 [95% CI 28.4, 37.3] per 100,000 admission per year [0.032%]. The annual incidence was least in 2015 (17.8 per 100,000 admissions) and highest in 2018 (44.4 per 100,000 admissions). Eighty-six subjects had DVT, and 109 had PE, whereas 14 had both. And, 67.5% of the patients developed VTE during admission while, 32.5% developed within 1 month of discharge. Moreover, 22.9% of the patients with PE developed pulmonary embolism after discharge from the hospital. VTE assessment was performed on 64.7% of the patients, and 69.7% received VTE prophylaxis in accordance with guidelines.

Conclusion

Although the occurrence of VTE among hospitalized patients in Qatar is low, healthcare providers need additional education and knowledge of VTE assessment and prophylaxis to follow guidelines for all patients at the time of admission. Furthermore, risk assessment for VTE should be done for all patients at the time of discharge to decide on post-discharge prophylaxis so that incidence of VTE after discharge can be minimized. Future studies should focus on patients who developed VTE after discharge from the hospital as well as on various risk factors.

Fondaparinux sodium and low molecular weight heparin for venous thromboembolism prophylaxis in Chinese patients with major orthopedic surgery or trauma: a real-world study

Background

The present real-world study aimed to compare the efficacy and safety between fondaparinux sodium (FPX) and low molecular weight heparin (LMWH) for venous thromboembolism (VTE) prophylaxis in Chinese patients with major orthopedic surgery or trauma.

Methods

A total of 2429 patients, with major orthopedic surgery or trauma, underwent FPX (n = 1177) or LMWH (n = 1252) for VTE prophylaxis and were retrospectively reviewed. Primary outcomes, including in-hospital VTE and in-hospital major bleeding incidences, as well as the secondary outcomes, including in-hospital minor bleeding, in-hospital death, and VTE/bleeding/death within 2 months after discharge, were analyzed. Inverse probability of treatment weighting (IPTW) was conducted.

Results

FPX group exhibited lower in-hospital VTE (0.1% vs. 0.8%; P = 0.032, crude OR = 0.11 before IPTW; P = 0.046, weighted OR = 0.12 after IPTW) and in-hospital minor bleeding (17.8% vs. 26.8%; P < 0.001, crude OR = 0.59 before IPTW; P < 0.001, weighted OR = 0.67 after IPTW) compared to LMWH group. Furthermore, no difference of in-hospital major bleeding, in-hospital death, and VTE/bleeding/death within 2 months after discharge was observed between FPX group and LMWH group (all P > 0.05). Further subgroup analyses identified, in specific cluster of patients such as older age, renal function impairment, hypertension and so on, in-hospital VTE was declined in FPX group compared to LMWH group (all P < 0.001).

Conclusions

FPX is probable to exhibit a superior thromboprophylaxis efficacy compared with LMWH in in-hospital patients with major orthopedic surgery or trauma, especially in some special patients such as older age, renal function impairment, hypertension, etc.

Effects of Computerised Clinical Decision Support on Adherence to VTE Prophylaxis Clinical Practice Guidelines among Hospitalised Patients

OBJECTIVE

Venous thromboembolism (VTE) is an important patient safety concern. VTE leads to significant mortality and morbidity and a burden on healthcare resources. Despite the widespread availability of evidence-based clinical practice guidelines on VTE prophylaxis, we found that only 50.9% of our patients were receiving appropriate prophylaxis. The purpose of this study was to evaluate the impact of automation of an adapted VTE prophylaxis CPG using a clinical decision support system (the VTE-CDSS) on VTE prevention among hospitalised adult patients.

DESIGN AND SETTING

A quasi-experimental study (pre- and post-implementation) was conducted at a large 900-bed tertiary teaching multi-specialty hospital in Riyadh, Saudi Arabia.

PARTICIPANTS

The 1809 adult patients in the study included 871 enrolled during the pre-implementation stage and 938 enrolled during the post-implementation stage.

INTERVENTION

Multi-faceted implementation interventions were utilised, including leadership engagement and support, quality and clinical champions, staff training and education and regular audit and feedback.

MAIN OUTCOME MEASURE

Two rate-based process measures were calculated for each admission cohort (i.e. pre- and post-implementation): the percentage of inpatients who were assessed for VTE risk on admission and the percentage of inpatients who received appropriate VTE prophylaxis. Two outcome measures were calculated: the prevalence of hospital-acquired VTE (HA-VTE) events and the in-hospital all-cause mortality.

RESULTS

The percentage of inpatients risk assessed for VTE on admission increased from 77.4% to 93.3% (P < 0.01). The percentage of patients who received appropriate VTE prophylaxis increased from 50.9% to 81.4% (P < 0.01). The HA-VTE events decreased by 50% from 0.33% to 0.15% (P < 0.01).All-cause in-hospital mortality did not significantly change after implementation of the VTE-CDSS compared with pre-implementation mortality (P > 0.05).

CONCLUSION

The VTE-CDSS improved patient safety by enhancing adherence to the VTE prophylaxis best practice and adapted CPG. The multi-faceted implementation strategies approach improved the compliance rate of risk assessment and the adherence to prophylaxis recommendations and substantially reduced the HA-VTE prevalence. A successful CDSS requires a set of critical components to ensure better user compliance and positive patient outcomes.

Call to Action to Prevent Venous Thromboembolism in Hospitalized Patients: A Policy Statement From the American Heart Association

Venous thromboembolism (VTE) is a major preventable disease that affects hospitalized inpatients. Risk stratification and prophylactic measures have good evidence supporting their use, but multiple reasons exist that prevent full adoption, compliance, and efficacy that may underlie the persistence of VTE over the past several decades. This policy statement provides a focused review of VTE, risk scoring systems, prophylaxis, and tracking methods. From this summary, 5 major areas of policy guidance are presented that the American Heart Association believes will lead to better implementation, tracking, and prevention of VTE events. They include performing VTE risk assessment and reporting the level of VTE risk in all hospitalized patients, integrating preventable VTE as a benchmark for hospital comparison and pay-for-performance programs, supporting appropriations to improve public awareness of VTE, tracking VTE nationwide with the use of standardized definitions, and developing a centralized data steward for data tracking on VTE risk assessment, prophylaxis, and rates.

Recommendations for VTE Prophylaxis in Medically Ill Patients

Venous thromboembolism (VTE) remains highly prevalent in medically ill patients, and often leads to increased mortality and cost burden during hospitalization and post-discharge. Nearly half of all VTEs occur during or after hospitalization, with pulmonary embolism accounting for 10% of inpatient mortality. Appropriate prophylaxis in high-risk medically ill patients has been shown to reduce risk of VTE and related mortality. Despite current evidence-based guidelines, VTE prophylaxis has been under-used. This owes greatly to ambiguity and concerns related to appropriate patient and prophylactic agent selection, and duration of prophylaxis. Because many acutely ill medical patients have multiple comorbidities, the risk of major bleeding must be considered when choosing to implement pharmacological VTE prophylaxis. Multiple risk assessment models have been developed and validated to help estimate VTE and bleeding risks in this population. While studies have shown that the risk for VTE often extends far beyond hospital discharge, there is no evidence to support extending prophylaxis after hospital discharge. The appropriate selection of VTE prophylaxis requires consideration for cost, availability, patient preference, compliance, and underlying comorbidities. Our paper reviews the current evidence and reasoning for appropriate selection of VTE prophylaxis in acutely medical ill patients, and highlights our own approach and recommendations.

Betrixaban for prevention of venous thromboembolism in acute medically ill patients

Venous thromboembolism (VTE) is a common, potentially preventable cause of morbidity and mortality among acute medically ill patients. More than half of VTE events in this population occur after hospital discharge. Thus, providing extended-duration VTE prophylaxis from in-hospital through the post-discharge continuum may improve the quality of care in patients at risk of VTE. Betrixaban is a new oral, once-daily factor Xa inhibitor approved by the United States (US) Food and Drug Administration (FDA) for extended-duration prophylaxis of VTE in acute medically ill patients. The clinical efficacy and safety of betrixaban in acute medically ill patients perceived to be at high risk for VTE were evaluated in a large, randomized, double-blind, active-controlled, multinational clinical trial [Acute Medically Ill VTE Prevention With Extended Duration Betrixaban (APEX)]. Patients were randomized to receive subcutaneous enoxaparin (10 ± 4 days) or oral betrixaban (35–42 days) plus matching placebos. The primary efficacy outcome was a composite of asymptomatic proximal deep vein thrombosis and symptomatic VTE; the primary safety measure was major bleeding. Extended-duration betrixaban reduced VTE events without an increase in major bleeding in the modified intent-to-treat analysis. Post hoc analyses of the APEX trial provided further evidence to support the efficacy and safety of betrixaban in reducing all-cause ischaemic stroke, fatal or irreversible ischaemic or bleeding events, as well as reducing VTE-related rehospitalization. In summary, analyses of the APEX study demonstrated a positive benefit–risk profile for extended prophylaxis of VTE with betrixaban in acute medically ill patients. This is likely to have important public health and health economic implications.

Reducing the burden of venous thromboembolism in the acute medically ill population with extended-duration thromboprophylaxis

Hospitalized acute medically ill patients are vulnerable to venous thromboembolism (VTE), known as hospital-acquired thrombosis (HAT). The elevated risk of HAT is usually due to a combination of factors, with immobility and a prothrombotic state due to acute illness being the most frequent. The HAT risk persists well after hospital discharge, with more than half of events occurring after patient release. These HAT events may be fatal, and patients who survive the initial event may be subject to VTE recurrence, chronic discomfort from post-thrombotic syndrome and, although rare, may develop chronic thrombo-embolic pulmonary hypertension, which is often debilitating. The risk of HAT can be reduced with effective thromboprophylaxis. Current guidelines recommend thromboprophylaxis with subcutaneous heparin, low molecular weight heparin (LMWH) or fondaparinux for at-risk acute medically ill patients, but reports of real-world practice indicated that some patients do not receive protection in the short-term as outlined by the guidelines. Previous studies that have assessed extended thromboprophylaxis for 4-5 weeks with LMWH or direct oral anticoagulants in medically ill patients found they did not offer a net clinical benefit; any demonstrated efficacy was outweighed by the significantly increased risk of major haemorrhage. Therefore, there is an ongoing need for improved VTE prevention without increasing the risk of bleeding. In the APEX trial, conducted in an acute medically ill population, betrixaban provided a significant reduction in VTE events after 35 to 42 days of treatment compared with short-term enoxaparin without an increase in major bleeding.

Interventions for implementation of thromboprophylaxis in hospitalized patients at risk for venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in hospitalized patients. While numerous randomized controlled trials (RCTs) have shown that the appropriate use of thromboprophylaxis in hospitalized patients at risk for VTE is safe, effective, and cost-effective, thromboprophylaxis remains underused or inappropriately used. Our previous review suggested that system-wide interventions, such as education, alerts, and multifaceted interventions were more effective at improving the prescribing of thromboprophylaxis than relying on individual providers' behaviors. However, 47 of the 55 included studies in our previous review were observational in design. Thus, an update to our systematic review, focused on the higher level of evidence of RCTs only, was warranted.

OBJECTIVES

To assess the effects of system-wide interventions designed to increase the implementation of thromboprophylaxis and decrease the incidence of VTE in hospitalized adult medical and surgical patients at risk for VTE, focusing on RCTs only.

SEARCH METHODS

Our research librarian conducted a systematic literature search of MEDLINE Ovid, and subsequently translated it to CENTRAL, PubMed, Embase Ovid, BIOSIS Previews Ovid, CINAHL, Web of Science, the Database of Abstracts of Reviews of Effects (DARE; in the Cochrane Library), NHS Economic Evaluation Database (EED; in the Cochrane Library), LILACS, and clinicaltrials.gov from inception to 7 January 2017. We also screened reference lists of relevant review articles. We identified 12,920 potentially relevant records.

SELECTION CRITERIA

We included all types of RCTs, with random or quasi-random methods of allocation of interventions, which either randomized individuals (e.g. parallel group, cross-over, or factorial design RCTs), or groups of individuals (cluster RCTs (CRTs)), which aimed to increase the use of prophylaxis or appropriate prophylaxis, or decrease the occurrence of VTE in hospitalized adult patients. We excluded observational studies, studies in which the intervention was simply distribution of published guidelines, and studies whose interventions were not clearly described. Studies could be in any language.

DATA COLLECTION AND ANALYSIS

We collected data on the following outcomes: the number of participants who received prophylaxis or appropriate prophylaxis (as defined by study authors), the occurrence of any VTE (symptomatic or asymptomatic), mortality, and safety outcomes, such as bleeding. We categorized the interventions into alerts (computer or human alerts), multifaceted interventions (combination of interventions that could include an alert component), educational interventions (e.g. grand rounds, courses), and preprinted orders (written predefined orders completed by the physician on paper or electronically). We meta-analyzed data across RCTs using a random-effects model. For CRTs, we pooled effect estimates (risk difference (RD) and risk ratio (RR), with 95% confidence interval (CI), adjusted for clustering, when possible. We pooled results if three or more trials were available for a particular intervention. We assessed the certainty of the evidence according to the GRADE approach.

MAIN RESULTS

From the 12,920 records identified by our search, we included 13 RCTs (N = 35,997 participants) in our qualitative analysis and 11 RCTs (N = 33,207 participants) in our meta-analyses.

PRIMARY OUTCOME

Alerts were associated with an increase in the proportion of participants who received prophylaxis (RD 21%, 95% CI 15% to 27%; three studies; 5057 participants; I² = 75%; low-certainty evidence). The substantial statistical heterogeneity may be in part explained by patient types, type of hospital, and type of alert. Subgroup analyses were not feasible due to the small number of studies included in the meta-analysis.Multifaceted interventions were associated with a small increase in the proportion of participants who received prophylaxis (cluster-adjusted RD 4%, 95% CI 2% to 6%; five studies; 9198 participants; I² = 0%; moderate-certainty evidence). Multifaceted interventions with an alert component were found to be more effective than multifaceted interventions that did not include an alert, although there were not enough studies to conduct a pooled analysis.

SECONDARY OUTCOMES

Alerts were associated with an increase in the proportion of participants who received appropriate prophylaxis (RD 16%, 95% CI 12% to 20%; three studies; 1820 participants; I² = 0; moderate-certainty evidence). Alerts were also associated with a reduction in the rate of symptomatic VTE at three months (RR 64%, 95% CI 47% to 86%; three studies; 5353 participants; I² = 15%; low-certainty evidence). Computer alerts were associated with a reduction in the rate of symptomatic VTE, although there were not enough studies to pool computer alerts and human alerts results separately.

AUTHORS' CONCLUSIONS

We reviewed RCTs that implemented a variety of system-wide strategies aimed at improving thromboprophylaxis in hospitalized patients. We found increased prescription of prophylaxis associated with alerts and multifaceted interventions, and increased prescription of appropriate prophylaxis associated with alerts. While multifaceted interventions were found to be less effective than alerts, a multifaceted intervention with an alert was more effective than one without an alert. Alerts, particularly computer alerts, were associated with a reduction in symptomatic VTE at three months, although there were not enough studies to pool computer alerts and human alerts results separately.Our analysis was underpowered to assess the effect on mortality and safety outcomes, such as bleeding.The incomplete reporting of relevant study design features did not allow complete assessment of the certainty of the evidence. However, the certainty of the evidence for improvement in outcomes was judged to be better than for our previous review (low- to moderate-certainty evidence, compared to very low-certainty evidence for most outcomes). The results of our updated review will help physicians, hospital administrators, and policy makers make practical decisions about adopting specific system-wide measures to improve prescription of thromboprophylaxis, and ultimately prevent VTE in hospitalized patients.

Should all acutely ill medical patients be treated with antithrombotic drugs?

After reports from observational studies suggesting an association between acutely ill medical patients and venous thromboembolism (VTE), interventional trials with anticoagulants drugs have demonstrated a significant reduction of VTE during and immediately after hospitalisation. Although several guidelines suggest the clinical relevance of reducing this outcome, there is a low tendency to use anticoagulants in patients hospitalised for acute medical illness. We speculated that such underuse may be dependent on a low perception that patients included in the trials are actually at risk of thromboembolism. Therefore, the aim of this study was to analyse the clinical settings included in the interventional trials and their relationship with thrombotic risk. Analysis of interventional trials revealed that the majority of patients included in the trials (about 80%) were affected by heart failure, acute respiratory syndrome or infections. Among these three illnesses, literature data shows an association with venous thrombosis only in patients with acute infections; this finding was, however, supported only by retrospective study. On the contrary, there is scarce or no evidence that heart failure and acute respiratory syndrome are associated with venous thrombosis. These data underscore the need of better defining the thrombotic risk profile of acutely ill medical patients included in interventional trials with anticoagulants.

Preventing acute care-associated venous thromboembolism in adult and pediatric patients across a large healthcare system

BACKGROUND

Although effective methods for venous thromboembolism prophylaxis (VTE-P) have been known for decades, reliable implementation has been challenging.

OBJECTIVE

Develop reliable VTE-P systems for adult and for pediatric patients to reduce preventable venous thromboembolism (VTE).

DESIGN

We used a discovery and diffusion system to first develop an effective system in 1 hospital location, and then spread the principle best practices across the entire 22-hospital system.

SETTING

Twenty-two Mayo Clinic hospitals (adults and children).

PATIENTS

Adult and pediatric patients.

INTERVENTION

(1) Ensure that a VTE-P is declared at admission by providing a mandatory VTE-P "tollgate" that requires the provider to assess the risk for VTE and provide an appropriate order for VTE-P. (2) Use clinical decision support to provide ongoing surveillance and alerts to providers when there is a lapse in the VTE-P plan.

MEASUREMENTS

In adults, VTE compliance as measured by the Centers for Medicare and Medicaid Services Core Measures VTE-1 and VTE-2, preventable VTE as measured by VTE-6, and in pediatric patients, appropriate VTE measures as determined by chart audit.

RESULTS

VTE-1 and VTE-2 have approached 97% to 100% and preventable VTE has declined to 0% for the last 3 quarters. Similarly, the pediatric VTE-P screening tool was evaluated and piloted with >92% compliance in risk documentation, appropriate VTE-P >64%, and 0 VTE events during the study period.

CONCLUSION

An integrated system-wide approach can lead to measurable improvements in VTE-P process and outcome measures. Journal of Hospital Medicine 2016;11:S15-S21. © 2016 Society of Hospital Medicine.

Antiplatelet versus anticoagulation treatment for patients with heart failure in sinus rhythm

BACKGROUND

Morbidity in patients with chronic heart failure is high, and this predisposes them to thrombotic complications, including stroke and thromboembolism, which in turn contribute to high mortality. Oral anticoagulants (e.g. warfarin) and antiplatelet agents (e.g. aspirin) are the principle oral antithrombotic agents. Many heart failure patients with sinus rhythm take aspirin because coronary artery disease is the leading cause of heart failure. Oral anticoagulants have become a standard in the management of heart failure with atrial fibrillation. However, a question remains regarding the appropriateness of oral anticoagulants in heart failure with sinus rhythm. This update of a review previously published in 2012 aims to address this question.

OBJECTIVES

To assess the effects of oral anticoagulant therapy versus antiplatelet agents for all-cause mortality, non-fatal cardiovascular events and risk of major bleeding in adults with heart failure (either with reduced or preserved ejection fraction) who are in sinus rhythm.

SEARCH METHODS

We updated the searches in September 2015 on CENTRAL (The Cochrane Library), MEDLINE and Embase. We searched reference lists of papers and abstracts from cardiology meetings and contacted study authors for further information. We did not apply any language restrictions. Additionally, we searched two clinical trials registers: ClinicalTrials.gov (www.ClinicalTrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) Search Portal apps.who.int/trialsearch/) (searched in July 2016).

SELECTION CRITERIA

We included randomised controlled trials comparing antiplatelet therapy versus oral anticoagulation in adults with chronic heart failure in sinus rhythm. Treatment had to last at least one month. We compared orally administered antiplatelet agents (aspirin, ticlopidine, clopidogrel, prasugrel, ticagrelor, dipyridamole) versus anticoagulant agents (coumarins, warfarin, non-vitamin K oral anticoagulants).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed the risks and benefits of antithrombotic versus antiplatelet therapy using relative measures of effects, such as risk ratios (RR), accompanied with 95% confidence intervals (CI). The data extracted included data relating to the study design, patient characteristics, study eligibility, quality, and outcomes. We used GRADE criteria to assess the quality of the evidence.

MAIN RESULTS

This update identified one additional study for inclusion, adding data for 2305 participants. This addition more than doubled the overall number of patients eligible for the review. In total, we included four randomised controlled trials (RCTs) with a total of 4187 eligible participants. All studies compared warfarin with aspirin. One RCT additionally compared warfarin with clopidogrel. All included RCTs studied patients with heart failure with reduced ejection fraction.Analysis of all outcomes for warfarin versus aspirin was based on 3663 patients from four RCTs. All-cause mortality was similar for warfarin and aspirin (RR 1.00, 95% CI 0.89 to 1.13; 4 studies; 3663 participants; moderate quality evidence). Oral anticoagulation was associated with a reduction in non-fatal cardiovascular events, which included non-fatal stroke, myocardial infarction, pulmonary embolism, peripheral arterial embolism (RR 0.79, 95% CI 0.63 to 1.00; 4 studies; 3663 participants; moderate quality evidence). The rate of major bleeding events was twice as high in the warfarin groups (RR 2.00, 95% CI 1.44 to 2.78; 4 studies; 3663 participants; moderate quality evidence). We generally considered the risk of bias of the included studies to be low.Analysis of warfarin versus clopidogrel was based on a single RCT (N = 1064). All-cause mortality was similar for warfarin and clopidogrel (RR 0.93, 95% CI 0.72 to 1.21; 1 study; 1064 participants; low quality evidence). There were similar rates of non-fatal cardiovascular events (RR 0.85, 95% CI 0.50 to 1.45; 1 study; 1064 participants; low quality evidence). The rate of major bleeding events was 2.5 times higher in the warfarin group (RR 2.47, 95% CI 1.24 to 4.91; 1 study; 1064 participants; low quality evidence). Risk of bias for this study can be summarised as low.

AUTHORS' CONCLUSIONS

There is evidence from RCTs to suggest that neither oral anticoagulation with warfarin or platelet inhibition with aspirin is better for mortality in systolic heart failure with sinus rhythm (high quality of the evidence for all-cause mortality and moderate quality of the evidence for non-fatal cardiovascular events and major bleeding events). Treatment with warfarin was associated with a 20% reduction in non-fatal cardiovascular events but a twofold higher risk of major bleeding complications (high quality of the evidence). We saw a similar pattern of results for the warfarin versus clopidogrel comparison (low quality of the evidence). At present, there are no data on the role of oral anticoagulation versus antiplatelet agents in heart failure with preserved ejection fraction with sinus rhythm. Also, there were no data from RCTs on the utility of non-vitamin K antagonist oral anticoagulants compared to antiplatelet agents in heart failure with sinus rhythm.

Preventing Thrombosis to Improve Outcomes in Heart Failure Patients

Heart failure (HF) is associated with an increased risk of thrombotic events, particularly if this condition is accompanied by atrial fibrillation (AF). Many HF patients have background coronary artery disease (CAD) making them prone to coronary thrombosis resulting in myocardial infarction or sudden death. Oral anticoagulation is essential in the vast majority of HF patients with AF with non-vitamin K based anticoagulants being a suitable alternative to warfarin. In contrast, aspirin alone does not provide adequate stroke prevention in such patients. In HF without AF, oral anticoagulation should not be routinely used, and antiplatelet agents should be prescribed in patients with background CAD. This review provides an overview of prothrombotic factors and antithrombotic management of patients with HF.

The effect of chronic liver disease on venous thromboembolism among medically managed patients in Singapore General Hospital

BACKGROUND

Chronic liver disease (CLD) has been suggested to be associated with venous thromboembolism (VTE) in western populations. However, little is known about the risk effects of CLD on VTE among Asians.

OBJECTIVE

To compute the prevalence of VTE among hospitalised Asian patients, and to evaluate the pattern and scale of risk effects of CLD on VTE occurrence.

METHOD

Retrospective study of hospital discharge database from 2004 to 2011 to identify patients with VTE and CLD using International Statistical Classification of Diseases and Related Health Problems, 9th Revision, Australian Modification (ICD-9-AM) codes.

RESULTS

Of 199904 medically managed inpatients during the 8years, 1744 (0.9%) patients had VTE. Patients with CLD had significant higher prevalence of VTE (non-cirrhosis CLD 1.5%, cirrhosis 2.0%) than patients without CLD (0.8%, p<0.001). In the logistic regression analyses, non-cirrhosis CLD (odds ratio, OR 1.4, 95% CI 1.2-1.7, p<0.001) and cirrhosis (OR 1.5, 95% CI 1.2-2.0, p=0.002) were significant predictors of VTE after adjustment for age, gender, ethnicity, hospital long stayer, cancer, infectious disease, and other comorbid conditions such as diabetic mellitus, anaemia, and cardiovascular, cerebrovascular, renal and pulmonary diseases.

CONCLUSION

CLD, particular liver cirrhosis, increases the risks of VTE in hospitalised Asian patients. As CLD patients are perceived to be at risks of bleeding due to the prolonged clotting times and thrombocytopenia, the results of this study brings attention to opposite end of the haemostatic pendulum in patients with chronic liver disease.

Influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism

BACKGROUND

The influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism (VTE) has not been thoroughly studied.

METHODS

We used the RIETE Registry data to compare the 3-month mortality rate in cancer patients with VTE, with patients categorized according to the presence of recent immobilization, surgery or neither. The major outcomes were fatal pulmonary embolism (PE) and fatal bleeding within the first 3 months.

RESULTS

Of 6,746 patients with active cancer and acute VTE, 1,224 (18%) had recent immobilization, 1,055 (16%) recent surgery, and 4,467 (66%) had neither. The all-cause mortality was 23.4% (95% CI: 22.4-24.5), and the PE-related mortality: 2.5% (95% CI: 2.1-2.9). Four in every ten patients dying of PE had recent immobilization (37%) or surgery (5.4%). Only 28% of patients with immobilization had received prophylaxis, as compared with 67% of the surgical. Fatal PE was more common in patients with recent immobilization (5.0%; 95% CI: 3.9-6.3) than in those with surgery (0.8%; 95% CI: 0.4-1.6) or neither (2.2%; 95% CI: 1.8-2.6). On multivariate analysis, patients with immobilization were at an increased risk for fatal PE (odds ratio: 1.8; 95% CI: 1.2-2.5).

CONCLUSIONS

One in every three cancer patients dying of PE had recent immobilization for ≥ 4 days. Many of these deaths could have been prevented with adequate thromboprophylaxis.

Prevention of venous thromboembolism in hospitalized acutely ill medical patients: focus on the clinical utility of (low-dose) fondaparinux

Venous thromboembolism (VTE) is a frequent complication among acutely ill medical patients hospitalized for congestive heart failure, acute respiratory insufficiency, rheumatologic disorders, and acute infectious and/or inflammatory diseases. Based on robust data from randomized controlled studies and meta-analyses showing a reduced incidence of VTE by 40% to about 60% with pharmacologic thromboprophylaxis, prevention of VTE with low molecular weight heparin (LMWH), unfractionated heparin (UFH), or fondaparinux is currently recommended in all at-risk hospitalized acutely ill medical patients. In patients who are bleeding or are at high risk for major bleeding, mechanical prophylaxis with graduated compression stockings or intermittent pneumatic compression may be suggested. Thromboprophylaxis is generally continued for 6 to 14 days or for the duration of hospitalization. Selected cases could benefit from extended thromboprophylaxis beyond this period, although the risk of major bleeding remains a concern, and additional studies are needed to identify patients who may benefit from prolonged prophylaxis. For hospitalized acutely ill medical patients with renal insufficiency, a low dose (1.5 mg once daily) of fondaparinux or prophylactic LMWH subcutaneously appears to have a safe profile, although proper evaluation in randomized studies is lacking. The evidence on the use of prophylaxis for VTE in this latter group of patients, as well as in those at higher risk of bleeding complications, such as patients with thrombocytopenia, remains scarce. For critically ill patients hospitalized in intensive care units with no contraindications, LMWH or UFH are recommended, with frequent and careful assessment of the risk of bleeding. In this review, we discuss the evidence for use of thromboprophylaxis for VTE in acutely ill hospitalized medical patients, with a focus on (low-dose) fondaparinux.

Safety and efficacy of new anticoagulants in patients with heart failure

Heart failure (HF) is a common and growing health problem with high morbidity and mortality rates. Thromboembolism is a major contributor to the poor prognosis of HF patients. HF independently increases the risk of thromboembolism, and the high incidence of atrial fibrillation (AF) in HF patients further adds to the risk of thromboembolic events. The reviewed evidence for the efficacy of anticoagulation in HF patients shows a potential preventive effect of oral anticoagulation in thromboembolism-in particular, risk reduction for stroke-but this is offset by an increased risk of major bleeding. However, given the inhomogeneity of the HF cohorts, the diagnosis of AF warranting oral anticoagulation, the increasing awareness of the potential of bleeding risk assessment, and the advantages of the new oral anticoagulants, the future of thromboembolic prevention in HF patients could very well be brighter than it appears and help improve outcomes for this large group of patients.

Thromboembolism and antithrombotic therapy for heart failure in sinus rhythm: an executive summary of a joint consensus document from the ESC Heart Failure Association and the ESC Working Group on Thrombosis

Chronic heart failure (HF) with either reduced or preserved left ventricular (LV) ejection fraction is common and remains an extremely serious disorder with a high mortality and morbidity. Many complications related to heart failure can be related to thrombosis. Epidemiological and pathophysiological data also link HF to an increased risk of thrombosis, leading to the clinical consequences of sudden death, stroke, systemic thromboembolism and/or venous thromboembolism. This executive summary of a joint consensus document of the Heart Failure Association (EHFA) of the European Society of Cardiology (ESC) and the ESC Working Group on Thrombosis reviews the published evidence, summarises 'best practice', and puts forward consensus statements that may help to define evidence gaps and assist management decisions in everyday clinical practice. In HF patients with atrial fibrillation, oral anticoagulation is clearly recommended, and the CHA2DS2-VASc and HAS-BLED scores should be used to determine the likely risk-benefit ratio (thromboembolism prevention versus risk of bleeding) of oral anticoagulation. In HF patients with reduced LV ejection fraction who are in sinus rhythm there is no evidence of an overall benefit of vitamin K antagonists (e.g. warfarin) on mortality, with risk of major bleeding. Whilst there is the potential for a reduction in ischaemic stroke, there is currently no compelling reason to routinely use warfarin for these patients. Risk factors associated with increased risk of thromboembolic events should be identified and decisions regarding use of anticoagulation individualised. Patient values and preferences are important determinants when balancing the risk of thromboembolism against bleeding risk. Novel oral anticoagulants that offer a different risk-benefit profile compared with warfarin may appear as an attractive therapeutic option, but this would need to be confirmed in clinical trials.

Influence of recent immobilization and recent surgery on mortality in patients with pulmonary embolism

BACKGROUND

The influence of recent immobilization or surgery on mortality in patients with pulmonary embolism (PE) is not well known.

METHODS

We used the Registro Informatizado de Enfermedad TromboEmbólica (RIETE) data to compare the 3-month mortality rate in patients with PE, with patients categorized according to the presence of recent immobilization, recent surgery, or neither.

RESULTS

Of 18,028 patients with PE, 4169 (23%) had recent immobilization, 2212 (12%) had recent surgery, and 11,647 (65%) had neither. The all-cause mortality was 10.0% (95% confidence interval [CI] 9.5-10.4), and the PE-related mortality was 2.6% (95% CI 2.4-2.9). One in every two patients who died from PE had recent immobilization (43%) or recent surgery (6.7%). Only 25% of patients with immobilization had received prophylaxis, as compared with 65% of the surgical patients. Fatal PE was more common in patients with recent immobilization (4.9%; 95% CI 4.3-5.6) than in those with surgery (1.4%; 95% CI 1.0-2.0) or those with neither (2.1%; 95% CI 1.8-2.3). On multivariate analysis, patients with immobilization were at increased risk for fatal PE (odds ratio 2.2; 95% CI 1.8-2.7), with no differences being seen between patients immobilized in hospital or in the community.

CONCLUSIONS

Forty-three per cent of patients dying from PE had recent immobilization for ≥4 days. Many of these deaths could have been prevented.

Thrombo-embolism and antithrombotic therapy for heart failure in sinus rhythm. A joint consensus document from the ESC Heart Failure Association and the ESC Working Group on Thrombosis

Chronic heart failure (HF) with either reduced or preserved ejection fraction is common and remains an extremely serious disorder with a high mortality and morbidity. Many complications related to HF can be related to thrombosis. Epidemiological and pathophysiological data also link HF to an increased risk of thrombosis, leading to the clinical consequences of sudden death, stroke, systemic thrombo-embolism, and/or venous thrombo-embolism. This consensus document of the Heart Failure Association (EHFA) of the European Society of Cardiology (ESC) and the ESC Working Group on Thrombosis reviews the published evidence and summarizes 'best practice', and puts forward consensus statements that may help to define evidence gaps and assist management decisions in everyday clinical practice. In HF patients with atrial fibrillation, oral anticoagulation is recommended, and the CHA(2)DS(2)-VASc and HAS-BLED scores should be used to determine the likely risk-benefit ratio (thrombo-embolism prevention vs. risk of bleeding) of oral anticoagulation. In HF patients with reduced left ventricular ejection fraction who are in sinus rhythm there is no evidence of an overall benefit of vitamin K antagonists (e.g. warfarin) on mortality, with risk of major bleeding. Despite the potential for a reduction in ischaemic stroke, there is currently no compelling reason to use warfarin routinely for these patients. Risk factors associated with increased risk of thrombo-embolic events should be identified and decisions regarding use of anticoagulation individualized. Patient values and preferences are important determinants when balancing the risk of thrombo-embolism against bleeding risk. New oral anticoagulants that offer a different risk-benefit profile compared with warfarin may appear as an attractive therapeutic option, but this would need to be confirmed in clinical trials.

Risk of venous thromboembolism in patients with chronic liver disease and the utility of venous thromboembolism prophylaxis

OBJECTIVE

To review the current literature on the risk of venous thromboembolism (VTE) in patients with chronic liver disease (CLD).

DATA SOURCES

Literature was accessed through MEDLINE/PubMed (1996-December 2011) using the search terms liver disease, cirrhosis, venous thromboembolism, deep vein thrombosis, and pulmonary embolism.

STUDY SELECTION AND DATA EXTRACTION

Relevant observational and population-based studies were included to present background information. Bibliographies of all relevant articles were reviewed for additional citations.

DATA SYNTHESIS

Liver disease affects the synthesis of procoagulants and anticoagulants, resulting in hemostatic alterations and abnormal laboratory values. Retrospective studies characterized the VTE incidence to be 0.5-6.3%. Population-based studies reported VTE relative risks of 1.74-2.10 in patients with CLD compared with population controls and VTE odds ratios of 0.9-1.39 for hospitalized patients with CLD compared with controls without liver disease. There is a paucity of data on the use of pharmacologic prophylaxis in patients with CLD.

CONCLUSIONS

Patients with CLD should be assessed for VTE risk and given VTE prophylaxis when the benefits outweigh the risks. Diagnoses of CLD or elevated international normalized ratio do not confer protection against development of VTE and do not justify withholding pharmacologic prophylaxis based on this diagnosis.

Experimental Validation of Methods for Prophylaxis against Deep Venous Thrombosis: A Review and Proposal

The experimental procedure by which the valve cusp hypoxia (VCH) hypothesis of the etiology of deep venous thrombosis (DVT) was confirmed lends itself to testing of methods of prophylaxis. Similar animal experiments could end the present exclusive reliance on statistical analysis of data from large patient cohorts to evaluate prophylactic regimes. The reduction of need for such (usually retrospective) analyses could enable rationally-based clinical trials of prophylactic methods to be conducted more rapidly, and the success of such trials would lead to decreased incidences of DVT-related mortality and morbidity. This paper reviews the VCH hypothesis ("VCH thesis", following its corroboration) and its implications for understanding DVT and its sequelae, and outlines the experimental protocol for testing prophylactic methods. The advantages and limitations of the protocol are briefly discussed.