The Consensus Statement is formed as a recommendation to the European Stroke Organisation (ESO) on revision of ESO Guidelines. Please note that the final text of the Guidelines, is decided by ESO and that the recommendation in this document may not be the final guidelines version. As soon as the guidelines are confirmed, they will appear on this website as well as on the ESO website www.eso-stroke.org

Karolinska Stroke Update Consensus Statement and Recommentations to the European Stroke Organisation Guidelines Committee

Prevention of Stroke in Atrial Fibrillation

The following Consensus Statement was adopted by the 8th Karolinska Stroke Update meeting on November 15, 2010.
The consensus statement was proposed by the chairmen of the session, Professor Gary Ford, Newcastle, and Professor Bo Norrving, Lund, and by the session secretary Associate Professor Mia von Euler, Stockholm, together with the speakers of the session. The statement was then finally approved by the participants of the meeting, after listening to the different presentations.
The speakers in this session were Professor Christoph Diener, Essen and Professor Didier Leys, Lille. 

Controversy to discuss at the 2010 consensus session:

• Is dabigatran superior to Warfarin in primary and secondary prevention of stroke in patients with atrial fibrillation, or is Warfarin still the beter alternative?

Please note, that Recommendations are pending regulatory (EMEA) approval of dabigatran and apixaban.

A. Primary prevention

For primary prevention of stroke in patients with atrial fibrillation we refer to the European Society of Cardiology’s guidelines for the management of atrial fibrillation (European Heart Journal 2010:31; 2369–2429).

B. Secondary prevention

For patients with TIA or ischemic stroke and atrial flutter and/or atrial fibrillation, irrespective of pattern, chronic oral anticoagulation (OAC) therapy is recommended. For patients commencing OAC treatment or patients on vitamin K antagonists (VKAs) with unstable INR (<75 % time in therapeutic range) treatment with dabigatran is recommended unless contraindicated. For patients with TIA or ischemic stroke and atrial fibrillation who are already on VKAs and have stable INRs ( >75% time in therapeutic range) VKAs are recommended in a dose adjusted regimen unless contraindicated. (Class I, Level A)

It is recommended that the selection of the antithrombotic therapy should be based upon the absolute risks of stroke/thrombo-embolism and bleeding, and the relative risk and benefit for a given patient. (Class IIa, Level C)

For patients who do not wish to take oral anticoagulants or patients in whom the treating physician considers VKAs inappropriate, apixaban is recommended unless contraindicated. (Class I, Level B)

For patients with TIA or ischemic stroke with AF with contraindications to any OAC antiplatelet therapy should be considered. (Class IV, Level C)

In patients with TIA or ischemic stroke and atrial fibrillation the risk-benefit ratio of the combination therapy of aspirin and clopidogrel is uncertain. (Class IIb, Level C) 
An assessment of the risk of bleeding in the individual patient should be made when prescribing antithrombotic therapy (whether with VKA, direct thrombin antagonist or Factor Xa antagonists). (Class IIa, Level B)  The HAS-BLED score [hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile INR, elderly (>65), drugs/alcohol concomitantly] should be undertaken as a calculation to assess bleeding risk.  A HAS-BLED score of >3 indicates ‘high risk’ and some caution and regular review is needed, following the initiation of antithrombotic therapy, whether with OAC or aspirin. (Class IIa, Level B)

In patients with AF presenting with acute stroke or TIA, management of uncontrolled hypertension is mandatory before antithrombotic treatment is started, and brain  imaging (computed tomography or magnetic resonance imaging) performed to exclude haemorrhage.  Caution should be exercised in small vessel disease.  (Class III, Level C)

Patients with TIA or ischemic stroke with atrial fibrillation who have mechanical heart valves should remain on VKAs. It is recommended that the target intensity of anticoagulation with a VKA should be based on the type and position of the prosthesis, maintaining an INR of at least 2.5 in the mitral position and at least 2.0 for an aortic valve. (Class I, Level B)

In the absence of haemorrhage, OAC therapy should be initiated once the risk of symptomatic haemorrhagic conversion into a cerebral infarct is less than the risk of recurrent stroke i.e.  after two weeks in patients with AF and moderate to severe stroke (Class III, Level C). In patients with TIA or minor non-disabling stroke OAC therapy may be considered at an earlier stage. (Class IV, Level C)

In patients with intracranial haemorrhage and atrial fibrillation, the relationship between stroke risk and bleeding risk (HAS-BLED) has to be considered.  Re-initiation of OAC could be considered 6 weeks after intracranial haemorrhage in patients with a high risk of embolic stroke and a low risk of recurrent intracranial bleeding.  Recent brain imaging is required for this decision. In patients with a high risk of recurrent bleeds (e.g. amyloid angiopathy, frequent falls in chronic alcoholism) OAC is not recommended. (Class IIa, Level C)

Following surgical procedures, resumption of OAC therapy should be considered at the ‘usual’ maintenance dose (without a loading dose) on the evening of (or the next morning after) surgery, assuming there is adequate haemostasis. (Class IIa, Level B).