Which type of murmur is best described as holosystolic?

Holosystolic murmurs are characterized by a sound that occurs throughout the entire duration of systole, from the first heart sound (S1) to the second heart sound (S2). This type of murmur typically arises from conditions where there is backward flow of blood, indicating a failure of proper valve closure during contraction of the heart.

Mitral regurgitation is the classic example of a holosystolic murmur. In this condition, the mitral valve does not close properly during systole, allowing blood to flow from the left ventricle back into the left atrium throughout the entire systolic phase. Consequently, this results in a continuous sound that can be heard clearly over the precordium.

While tricuspid regurgitation also presents a holosystolic murmur, it is less commonly referenced compared to mitral regurgitation. Aortic stenosis and pulmonary stenosis produce systolic murmurs, but they are typically ejection-type murmurs that do not extend throughout the entire duration of systole. Hence, the clear-cut holosystolic nature of mitral regurgitation makes it the best representation of this specific type of murmur.