Editorial: do we need another bleeding definition? What does the Bleeding Academic Research Consortium definition have to offer?

Oral anticoagulants for primary prevention, treatment and secondary prevention of venous thromboembolic disease, and for prevention of stroke in atrial fibrillation: systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

Warfarin is effective for stroke prevention in atrial fibrillation (AF), but anticoagulation is underused in clinical care. The risk of venous thromboembolic disease during hospitalisation can be reduced by low-molecular-weight heparin (LMWH): warfarin is the most frequently prescribed anticoagulant for treatment and secondary prevention of venous thromboembolism (VTE). Warfarin-related bleeding is a major reason for hospitalisation for adverse drug effects. Warfarin is cheap but therapeutic monitoring increases treatment costs. Novel oral anticoagulants (NOACs) have more rapid onset and offset of action than warfarin, and more predictable dosing requirements.

OBJECTIVE

To determine the best oral anticoagulant/s for prevention of stroke in AF and for primary prevention, treatment and secondary prevention of VTE.

DESIGN

Four systematic reviews, network meta-analyses (NMAs) and cost-effectiveness analyses (CEAs) of randomised controlled trials.

SETTING

Hospital (VTE primary prevention and acute treatment) and primary care/anticoagulation clinics (AF and VTE secondary prevention).

PARTICIPANTS

Patients eligible for anticoagulation with warfarin (stroke prevention in AF, acute treatment or secondary prevention of VTE) or LMWH (primary prevention of VTE).

INTERVENTIONS

NOACs, warfarin and LMWH, together with other interventions (antiplatelet therapy, placebo) evaluated in the evidence network.

MAIN OUTCOME MEASURES

Efficacy Stroke, symptomatic VTE, symptomatic deep-vein thrombosis and symptomatic pulmonary embolism. Safety Major bleeding, clinically relevant bleeding and intracranial haemorrhage. We also considered myocardial infarction and all-cause mortality and evaluated cost-effectiveness.

DATA SOURCES

MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The Cochrane Library, reference lists of published NMAs and trial registries. We searched MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The Cochrane Library. The stroke prevention in AF review search was run on the 12 March 2014 and updated on 15 September 2014, and covered the period 2010 to September 2014. The search for the three reviews in VTE was run on the 19 March 2014, updated on 15 September 2014, and covered the period 2008 to September 2014.

REVIEW METHODS

Two reviewers screened search results, extracted and checked data, and assessed risk of bias. For each outcome we conducted standard meta-analysis and NMA. We evaluated cost-effectiveness using discrete-time Markov models.

RESULTS

Apixaban (Eliquis^®, Bristol-Myers Squibb, USA; Pfizer, USA) [5 mg bd (twice daily)] was ranked as among the best interventions for stroke prevention in AF, and had the highest expected net benefit. Edoxaban (Lixiana^®, Daiichi Sankyo, Japan) [60 mg od (once daily)] was ranked second for major bleeding and all-cause mortality. Neither the clinical effectiveness analysis nor the CEA provided strong evidence that NOACs should replace postoperative LMWH in primary prevention of VTE. For acute treatment and secondary prevention of VTE, we found little evidence that NOACs offer an efficacy advantage over warfarin, but the risk of bleeding complications was lower for some NOACs than for warfarin. For a willingness-to-pay threshold of > £5000, apixaban (5 mg bd) had the highest expected net benefit for acute treatment of VTE. Aspirin or no pharmacotherapy were likely to be the most cost-effective interventions for secondary prevention of VTE: our results suggest that it is not cost-effective to prescribe NOACs or warfarin for this indication.

CONCLUSIONS

NOACs have advantages over warfarin in patients with AF, but we found no strong evidence that they should replace warfarin or LMWH in primary prevention, treatment or secondary prevention of VTE.

LIMITATIONS

These relate mainly to shortfalls in the primary data: in particular, there were no head-to-head comparisons between different NOAC drugs.

FUTURE WORK

Calculating the expected value of sample information to clarify whether or not it would be justifiable to fund one or more head-to-head trials.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005324, CRD42013005331 and CRD42013005330.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Stent thrombosis: an overview

Stent thrombosis is a challenging problem following percutaneous coronary intervention that can lead to serious clinical consequences, such as death and acute myocardial infarction. Its pathophysiology is not yet completely known, and there are several causes suggested, such as incomplete stent endothelization, presence of polymers and late incomplete stent apposition. One of the main predictors is the early discontinuation of dual antiplatelet therapy. Stent improvements related to their design, with more friendly metallic platforms, thinner biocompatible or biodegradable polymers, absence of polymers, and even stents manufactured with bioabsorbable materials, could make the percutaneous procedure much safer and effective, allowing its application in increasingly complex anatomic and clinical scenarios, with low thrombosis rates.

The Use of Bivalirudin in ST-Segment Elevation Myocardial Infarction: Advantages and Limitations

The incidence of ST-segment elevation myocardial infarction (STEMI) is a common, albeit declining, manifestation of coronary heart disease. Significant improvements in cardiovascular outcomes and mortality in STEMI patients have occurred in recent years, reflecting evolution in the understanding of the pathophysiological mechanisms and therapeutic targets of this disease. Nonetheless, the risks of recurrent ischemia and bleeding complications in this population remain substantial. This review focuses on the adjunctive anticoagulant agents used in the management of STEMI. Major insights from the HORIZONS-AMI trial regarding the impact of bivalirudin on both hemorrhagic and ischemic outcomes in STEMI patients are discussed.

Validation of the Bleeding Academic Research Consortium Definition of Bleeding in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Background—

The Bleeding Academic Research Consortium (BARC) has recently proposed a unified definition of bleeding in patients receiving antithrombotic therapy. We investigated the relationship between bleeding events as defined by BARC and 1-year mortality in patients undergoing percutaneous coronary intervention (PCI) and assessed whether the BARC bleeding definition is superior to existing bleeding definitions in regard to mortality prediction in patients after PCI procedures.

Methods and Results—

This study represents a patient-level pooled analysis of 12 459 patients recruited in 6 randomized trials of patients undergoing PCI. Bleeding events were assessed with the use of BARC, Thrombolysis in Myocardial Infarction (TIMI), and Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) trial criteria. The primary outcome was 1-year mortality. Bleeding occurred in 1233 patients (9.9%) according to BARC (679 patients or 5.4% with BARC class ≥2 bleeding), in 374 patients (3.0%) according to TIMI, and in 491 patients (3.9%) according to REPLACE-2 criteria. There were 340 deaths (2.7%) over the first year after PCI. BARC class ≥2 bleeding was associated with a significant increase in 1-year mortality (adjusted hazard ratio 2.72; 95% confidence interval, 2.03–3.63). The predictivity of a multivariable model for 1-year mortality was significantly improved after inclusion of bleeding defined according to BARC to an extent comparable to that provided by TIMI and REPLACE-2 criteria.

Conclusions—

The present study demonstrated a close association between bleeding events defined according to BARC and 1-year mortality after PCI.