A diastolic murmur best heard at the left sternal border that increases when the patient leans forward indicates which valvular lesion?

• A. Aortic regurgitation
• B. Mitral stenosis
• C. Pulmonary regurgitation
• D. Tricuspid regurgitation

Answer: (A)

A diastolic murmur heard best along the left sternal border that becomes louder when the patient leans forward is characteristic of aortic regurgitation. During diastole, blood flows backward from the aorta into the left ventricle, producing a blowing, decrescendo murmur that is classically loudest at the left sternal border. Leaning forward brings the heart closer to the chest wall and, especially with expiration, enhances the transmission of this murmur, making it more conspicuous.

Mitral stenosis typically presents as a diastolic rumble at the apex, often with an opening snap, and is best heard in the left lateral decubitus position. Pulmonary regurgitation is a diastolic decrescendo murmur best heard at the left upper sternal border and is not characteristically intensified by leaning forward. Tricuspid regurgitation is a holosystolic murmur at the left lower sternal border, not a diastolic one.