This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Murmurs, Subject name: Medicine
[{'content': 'A 68-year-old man presents with progressive shoness of breath. He had a metallic hea valve replacement 13 years ago for severe aoic stenosis. Which of the following clinical findings is most indicative of a failing aoic valve replacement? \nSelect and explain. \nA. Clicking sound to S2, B. Early diastolic murmur heard at the left sternal edge, C. New onset atrial fibrillation, D. Ejection systolic murmur heard in the aoic region', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Option B: Early diastolic murmur heard at left sternal edge We know if metallic valves get older & undergo on sheering stress, so there will be backflow of blood from aoa to L.V so early diastolic murmur heard at left sternal edge. Severe aoic stenosis : 1.Transvalvular pressure gradient of > 40 mmHg. 2. Ejection velocity - >4 m/sec 3. Size of orifice - < 0.6 cm2/ m2 BSA', 'role': 'assistant'}]