Should all patients with AF be on warfarin all the time?

Dear Ask The Doctor: Hello my father who is 74 years old has had atrial fibrillation for about 10 years. It seems to come and go. He has had to have cardioversion about once a year since he was diagnosed. When his heart is not arrhythmic, he does not take any anti-coagulation medicine. should he be on warfarin all the time or is it ok for him to only go onto warfarin when his heart starts beating irregularly?

Dear Harriet: A patient with chronic atrial fibrillation needs to be on warfarin continuosly as this helps in keeping the blood thinner and also helps prevent clot formation due to the irregular rythym of the heart. This clot can then travel to the brain and lead to a stroke thus warfarin also acts like a prevetive medication. Moreover warfarin dosing and treatment needs close monitoring and it cannot be started and stopped as one wishes as that can lead to further problems and complications.