Which murmur has an opening snap followed by a diastolic murmur?

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

Answer: (D)

The combination of an opening snap after S2 followed by a diastolic murmur is characteristic of mitral stenosis. The opening snap occurs because the stiff, thickened mitral valve leaflets snap open once left atrial pressure exceeds ventricular pressure. After that sudden opening, blood flows through the narrowed orifice during diastole, producing a low-pitched, rumbling murmur best heard at the apex with the patient in the left lateral position, often with presystolic accentuation as the atrium contracts late in diastole. This pattern is typically seen in rheumatic heart disease and is not a feature of the other valves, whose diastolic murmurs (like early diastolic decrescendo for aortic or pulmonic regurg) or systolic murmurs (such as tricuspid regurg) do not include an opening snap.