I think MD's overprescribe blood thinners, and my cardiologist finally agreed. I have afib once a year or so, with heart rate 160-180, and always end up in ambulance. However I have declined blood thinners. I recently read that they have found short-term blood thinners for afib lasting more than 5.5 hours is better than long term blood thinners for those with infrequent afib. This has not yet been put into practice though. My last episode was 7 hours and they did an echocardiogram to check for clots in the heart. Aspirin is no longer recommended, both because it is not effective for this purpose and because of side effects. You can decline medications anytime you want to. If your afib is more frequent than mine, you could consider trying another anticoagulant.