News from EHRA: encouraging news on anticoagulants

Dr James Rosengarten reports highlights from the European Heart Rhythm Association (EHRA) Europace 2013 meeting held recently in Athens, Greece.

With the number of patients with atrial fibrillation (AF) set to double by 2050, appropriate anticoagulation for this growing condition was highlighted in a special session at the meeting – a ‘State of The Art Lecture’. Professor Stefan H Hohnloser (JW Goethe University, Frankfurt, Germany) described how stroke in Europe costs an estimated €38 billion per year, with 20% attributable to AF. Yet a decade ago, around 40% of AF patients did not receive appropriate anticoagulation. Of those receiving therapy, only around 50% of time in therapeutic range (TTR) is seen. With this in mind, novel oral anticoagulants (NOACs) are non-inferior to warfarin at reducing stroke risk, but also remove many of the therapeutic difficulties seen with oral anticoagulant therapy. The benefits of NOACs are seen even in those with previous stroke or impaired renal function.

Many of the difficulties with vitamin K antagonists (VKAs), such as warfarin, were seen in the past as good reason to avoid anticoagulation in all but the highest risk patients. Professor Gregory Y H Lip (University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham) believes we need to change the culture of under-prescribing thromboprophylaxis in AF. The focus has been on identifying those highest risk patients in whom benefits were believed to outweigh risks. However, a culture change is needed. NOACs now represent a more convenient and, in many respects, a safer option to VKA for stroke prophylaxis. The 2012 focussed update of the European Society of Cardiology (ESC) guidelines for the management of atrial fibrillation¹ recommend all but the lowest risk patients are indicated for oral anticoagulation. Attention should now be focussed on identifying these truly low risk individuals, scoring 0 or 1 on the CHA₂DS₂-VASc score.

Professor Lip also considered bleeding risk: the HAS-BLED score is a now well-validated score to identify those at risk of bleeding with oral anticoagulation. A score >3 is indicative of regular review and follow up, but should not be used as a reason for avoiding anticoagulation. In fact, patients with a high HAS-BLED score derive a higher net clinical benefit when balancing ischaemic stroke and intracranial bleeding.

Once you have identified your patient is at risk of stroke, which anticoagulant should you choose? The ESC guidelines recommend either a VKA with a high TTR, or a NOAC. A new scoring system – SAMe-TT₂R₂ (Sex female, Age less than 60, Medical history, Treatment strategy [rhythm control], Tobacco use [doubled] and race [doubled]) – can predict those who will do well with a VKA (a score of 0-1) or those who are likely to have poor anticoagulation control with a VKA (a score ≥2) and where a NOAC could be a better option.²

It is acknowledged that licensed indications and experience develops more quickly than guidelines can be updated. For this reason EHRA has published a Practical Guide on the use of NOACs in patients with non-valvular AF.³ This addresses many of the practical concerns relating to these novel agents, including initiation and follow up, drug interactions, dosing issues, bleeding and administration in patients requiring urgent surgery, or suffering with acute coronary events, or stroke.

James Rosengarten
Wessex Electrophysiology Fellow and BJCA Deanery Representative
([email protected])

References

1. Camm AJ, Lip GY, De Caterina R et al. 2012 focused update of the ESC Guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation–developed with the special contribution of the European Heart Rhythm Association. Europace 2012;14:1385-413. http://dx.doi.org/10.1093/europace/eus305
2. Apostolakis S, Sullivan RM, Olshansky B, Lip GY. Factors affecting quality of anticoagulation control amongst atrial fibrillation patients on warfarin: the SAMe-TT2R2 (Sex female, Age less than 60, Medical history, Treatment strategy [rhythm control], Tobacco use [doubled], Race [doubled]) score. Chest 2013; http://dx.doi.org/10.1378/chest.13-0054
3. Heidbuchel H, Verhamme P, Alings M et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-51. http://dx.doi.org/10.1093/europace/eut083