Which physical examination finding is characteristic of mitral stenosis?

Which physical examination finding is characteristic of mitral stenosis?

• A. Murmur best heard at apex in expiration
• B. Loud S1 with opening snap
• C. Fixed splitting of S2
• D. Systolic ejection murmur at the left upper sternal border

Answer: (B)

Mitral stenosis most clearly presents with a loud first heart sound accompanied by an opening snap. The stiff, thick mitral valve leaflets resist opening, so when they finally yield in early diastole, the abrupt opening creates that audible opening snap. The loud S1 reflects the forceful closure of the thickened valve. While the murmur of mitral stenosis is a diastolic rumble at the apex heard best with the patient in the left lateral position, the combination of a prominent S1 and an opening snap is the hallmark finding that distinguishes this lesion. Fixed splitting of S2 points to an atrial septal defect, and a systolic ejection murmur at the left upper sternal border suggests other valvular or outflow problems, not mitral stenosis.

Mitral stenosis most clearly presents with a loud first heart sound accompanied by an opening snap. The stiff, thick mitral valve leaflets resist opening, so when they finally yield in early diastole, the abrupt opening creates that audible opening snap. The loud S1 reflects the forceful closure of the thickened valve. While the murmur of mitral stenosis is a diastolic rumble at the apex heard best with the patient in the left lateral position, the combination of a prominent S1 and an opening snap is the hallmark finding that distinguishes this lesion. Fixed splitting of S2 points to an atrial septal defect, and a systolic ejection murmur at the left upper sternal border suggests other valvular or outflow problems, not mitral stenosis.