An opening snap is a characteristic finding in which cardiac condition?

An opening snap is a specific sound that is typically associated with mitral stenosis. This condition arises due to the narrowing of the mitral valve, which impedes blood flow from the left atrium to the left ventricle during diastole. As the mitral valve opens to allow blood flow, the stiffness of the deformed valve leaflets results in the characteristic "snap" sound.

In mitral stenosis, the opening snap occurs shortly after the second heart sound (S2) and can be followed by a diastolic rumble due to turbulent blood flow across the narrowed valve. The timing and nature of this sound are crucial for diagnosis, providing evidence of the degree of obstruction and the hemodynamic impact of the condition.

Other cardiac conditions listed, such as aortic stenosis, tricuspid regurgitation, and pulmonary stenosis, do not typically present with an opening snap. Instead, they manifest with different types of heart sounds and murmurs related to their specific pathophysiology. For instance, aortic stenosis is often associated with a systolic ejection murmur rather than a diastolic sound, and tricuspid regurgitation may present with a holosystolic murmur.