Commencing warfarin in the community

A 76-year-old woman presents with a new prescription for warfarin and atenoloL She is a regular customer of the pharmacy and has a history of hypertension (for which she takes perindoprillindapamide and amlodipine), type 2 diabetes (for which she takes metformin and gliclazide), and GORD (for which she takes esomeprazole), She also takes low dose aspirin and atorvastatin. On questioning, she tells you that she saw her GP after experiencing 'strange palpitations: An in-surgery ECG confirmed a diagnosis of atrial fibrillation. She is interested in learning more about atrial fibrillation and has many questions about warfarin.