Cardiovascularmiddle twist
A 52-year-old Aboriginal woman from a community in Cape York presents with a week of palpitations and breathlessness on walking to the store. She had several episodes of sore throat and joint pains as a child and was told she had "a heart problem" but stopped her monthly injections in her twenties. Her pulse is 118/min and irregularly irregular, and there is a low-pitched rumbling murmur best heard at the apex with the bell. An electrocardiogram confirms atrial fibrillation. Echocardiography shows thickened, doming mitral leaflets with a valve area of 1.2 cm² and a left atrial diameter of 52 mm. Her renal function is normal.
Which one of the following is the most appropriate long-term therapy to reduce her risk of stroke?