REVERSE II trial decision rule helps identify women who can safely discontinue anticoagulants

August 30, 2016

This press release accompanies both a presentation and an ESC press conference at the ESC Congress 2016. Edited by the ESC from material supplied by the investigators themselves, this press release does not necessarily reflect the opinion of the European Society of Cardiology. The content of the press release has been approved by the presenter.

Rome, Italy - 30 August 2016: A clinical decision rule (CDR) that can be applied to women after a first, unprovoked venous thromboembolism (VTE) was able to identify those with a low-risk of recurrence who could safely discontinue anticoagulant therapy, researchers reported at ESC Congress 2016.

The REVERSE II trial, presented in a Hot Line session here, prospectively validated the HERDOO2 rule, making it "the only currently validated CDR to assist clinicians, patients and policy makers to decide who can discontinue anticoagulants after unprovoked VTE," noted study investigator Marc Rodger, MD from the Ottawa Hospital and University of Ottawa, Ontario, Canada.

"This is an important finding as, using our rule, over half of women with unprovoked VTE (meaning VTE with no precipitant), can safely discontinue anticoagulants and be spared the burdens, costs, and risks of lifelong anticoagulation," he added. "Since current consensus guidelines suggest anticoagulants should be continued indefinitely in all patients with unprovoked VTE and non-high bleeding risk, our results are potentially practice-changing."

The HERDOO2 rule is named for the 4 risk factors that must be considered in determining a patient's risk of VTE recurrence:According to this rule, women (but not men) are considered low-risk if they have only one, or none of these risk factors.

The REVERSE II trial tested the HERDOO2 rule in a multi-national trial.

A total of 2,779 patients (mean age 54.4 years) with a first, unprovoked VTE were enrolled in the study, after completing at least 5, and up to 12 months of anticoagulant therapy.

After drop-outs and exclusions, 622 women were considered low-risk, based on HERDOO2 criteria, and the majority of these discontinued anticoagulant therapy.

In addition, most of the 591 high-risk women, as well as 1,534 men, for whom the HERDOO2 rule is not applicable, continued anticoagulant therapy.

After a year of follow-up, low-risk women who had discontinued anticoagulants had 3% rate of recurrent VTE per patient year (the primary outcome), compared to an 8.1% rate in high-risk patients who discontinued. The rate was 1.6% in high-risk patients who continued.

The question of duration of anticoagulation for the prevention of recurrent VTE after a first unprovoked event is controversial, and there are still some unanswered questions, noted Dr. Rodger.

"One is whether indefinite anticoagulation is required for men and high-risk women - and was not the primary focus of our study. The second is in the sub-group women of post-menopausal women aged 50 and above. In this group, even those who were considered low-risk according to the HERDOO2 rule had a higher than expected rate of recurrent VTE (5.7%) when they discontinued anticoagulants. As such, further validation of HERDOO2 is required in this sub-set of post-menopausal women."
Notes to editors

Sources of funding: This was an investigator-initiated study, sponsored by the Ottawa Hospital Research Institute, and funded by bioMe?rieux and a grant from the French Ministry of Health.

Disclosures: Dr. Rodger had no relevant disclosures.

ESC Press Office

For background information, please contact the ESC Press Office at

For press enquiries, please contact, the Media & Press Coordinator, Jacques Olivier Costa: +393427028575

For independent comment on site, please contact the ESC Spokesperson coordinator, Celine Colas: +393402405148

To access all the scientific resources from the sessions during the congress, visit ESC Congress 365.

About the European Society of Cardiology

The European Society of Cardiology brings together health care professionals from more than 120 countries, working to advance cardiovascular medicine and help people lead longer, healthier lives.

About ESC Congress 2016

ESC Congress is the world's largest gathering of cardiovascular professionals contributing to global awareness of the latest clinical trials and breakthrough discoveries. ESC Congress 2016 takes place 27 to 31 August at the Fiera di Roma in Rome, Italy. The scientific programme is here. More information is available from the ESC Press Office at

European Society of Cardiology

Related Anticoagulants Articles from Brightsurf:

Educational mailing fails to improve medication use in patients with atrial fibrillation
Prevention drugs, according to results of the IMPACT-AFib trial presented in a Hot Line session today at ESC Congress 2020.

Additional data on blood thinner efficacy for COVID-19 and insight on best possible regimens
Mount Sinai study is the basis of a new international clinical trial.

Researchers take a bloody good look at the medicinal leech genome
An international team of researchers, led by Royal Ontario Museum (ROM) scientist Sebastian Kvist, have announced the completion and results of their work to sequence the genome of Hirudo medicinalis, a European leech, and one of the most prominently used medicinal species.

Blood thinners may improve survival among hospitalized COVID-19 patients
Research could change standard of care protocols to prevent clotting associated with coronavirus.

Antiplatelet drugs increase risk for TAVR patients with atrial fibrillation
Patients with atrial fibrillation who took oral anticoagulants alone after undergoing transcatheter aortic valve replacement (TAVR) had a lower rate of bleeding complications without an increased risk of clotting-related complications compared to patients who took antiplatelet medication in addition to oral anticoagulants, in a trial presented at the American College of Cardiology's Annual Scientific Session Together with World Congress of Cardiology (ACC.20/WCC).

Bleeding may be a sign of bowel cancer not just a side-effect of blood-thinning drugs
Patients who are being treated with blood-thinning drugs for irregular heart beat should always be investigated for bowel cancer if they experience gastrointestinal bleeding, say the authors of a study published in the European Heart Journal.

Prescribing anticoagulants in the ED for atrial fibrillation increases long-term use by 30%
Patients prescribed anticoagulants after a diagnosis of atrial fibrillation in the emergency department are more likely to continue long-term use of medications to treat the condition, according to research published in CMAJ (Canadian Medical Association Journal).

33% of people on anticoagulants take OTC supplements with potentially serious interactions
Nearly 98% percent of people prescribed direct-acting oral anticoagulants such as apixaban used over-the-counter products.

Should patients continue blood thinners after experiencing gastrointestinal bleeding?
Anticoagulants and antiplatelet drugs, which are blood thinners such as warfarin and aspirin, are commonly taken to reduce the risk of potentially fatal blood clots, but they carry an increased risk of gastrointestinal bleeding.

Atrial fibrillation linked to increased risk of dementia, even in stroke-free patients
Atrial fibrillation is linked to an increased risk of dementia, even in people who have not suffered a stroke, according to the largest study to investigate the association in an elderly population published in the European Heart Journal.

Read More: Anticoagulants News and Anticoagulants Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to