Recommendation ID
Non-vitamin K antagonist oral anticoagulants:- Do people with atrial fibrillation whose anticoagulant control is poor, or is predicted to be poor, with warfarin benefit from changing to one of the non-vitamin K antagonist (non-VKA) oral anticoagulants?
Any explanatory notes
(if applicable)
Why this is important:- Trials of the non-vitamin K antagonist (VKA) oral anticoagulants have shown that the degree of benefit of these agents compared with warfarin may depend on the time in therapeutic range (TTR) of the warfarin group. These trials assessed the degree of benefit in relation to the mean TTR for the warfarin group in that country. However, the inference of benefit is based on a number of assumptions. It is unclear that the population TTR can be extrapolated to decision-making in an individual. If, for example, an individual's low TTR is a result of poor compliance, it is unlikely that compliance will improve with a non-VKA oral anticoagulant and uncertain whether a non-VKA oral anticoagulant will offer any benefit. Moreover, the threshold of TTR at which a non-VKA oral anticoagulant might offer benefit is unclear. The same question can be extended to include people before they start warfarin treatment, using criteria that prospectively identify those likely to have poor control on warfarin. A study with 2 arms should be carried out. One arm should randomise people with atrial fibrillation, whose control is poor with warfarin, to either continue warfarin treatment or change to a non-VKA oral anticoagulant. The other arm should randomise people newly diagnosed as having atrial fibrillation, who have not previously had anticoagulant therapy and in whom poor anticoagulant control is predicted (using the SAMe-TT2R2 score), to have treatment with either warfarin or a non-VKA oral anticoagulant. Outcomes should include stroke and other thromboembolic complications, major haemorrhage and death. [new 2014]

Source guidance details

Comes from guidance
Atrial fibrillation: management
Date issued
June 2014

Other details

Is this a recommendation for the use of a technology only in the context of research? No  
Is it a recommendation that suggests collection of data or the establishment of a register?   No  
Last Reviewed 13/10/2014