PANCE Cardiology Practice Test

This finding is classic for mitral stenosis. The opening snap happens when the stiff mitral valve leaflets first snap open early in diastole after S2, followed by a low-pitched, rumbling diastolic murmur as blood flows through the narrowed orifice from left atrium to left ventricle. The murmur is best heard at the apex with the patient in the left lateral decubitus position and tends to be softer later in diastole (a decrescendo). The combination of an opening snap plus a diastolic rumble is highly characteristic of mitral stenosis, usually from rheumatic disease. In contrast, tricuspid regurgitation gives a holosystolic murmur at the left lower sternal border; aortic regurgitation gives an early diastolic high-pitched blowing murmur along the left sternal border; and pulmonary stenosis produces a systolic murmur at the upper left sternal border.