MRCP2-0385

A 55-year-old man presents with palpitations. His ECG reveals atrial fibrillation with a ventricular rate of 80 beats per minute and his blood pressure is 120/80 mmHg. An echocardiogram shows well-preserved left ventricular function and moderate to severe mitral stenosis. The pulmonary artery pressure is 30 mmHg. What is the optimal approach for preventing stroke?