During your preoperative assessment, a 28-year-old woman complains of dyspnea on exeion. Upon auscultation of her hea, you notice a mid-diastolic rumbling murmur. This murmur is most characteristic of which valvular lesion

The murmur described is characteristic of mitral stenosis. The murmur of mitral stenosis is a mid-diastolic rumbling murmur, best heard at the apex with the patient in the left lateral position. The murmur of mitral regurgitation is typically a holosystolic murmur that may radiate to the axilla. The murmur associated with aoic regurgitation is a midsystolic ejection murmur generally heard best at the base of the hea and is transmitted to the jugular notch. The murmur associated with aoic stenosis is a mid-systolic crescendo- decrescendo murmur that often radiates to the carotids.