Which murmur is characterized as a regurgitant murmur heard throughout systole?

A pansystolic murmur, also known as a holosystolic murmur, is characterized by its presence throughout systole, starting with the first heart sound (S1) and extending to the second heart sound (S2). This type of murmur is a result of retrograde blood flow due to inadequate closure of the heart valves, commonly seen in conditions such as mitral regurgitation or tricuspid regurgitation.

The continuous nature of the murmur, without interruption, is what defines it as pansystolic. In contrast, murmurs related to aortic stenosis and mitral stenosis do not fit this description; aortic stenosis creates a systolic ejection murmur that occurs early in systole, while mitral stenosis often produces a mid-diastolic murmur due to turbulent blood flow when the blood moves from the left atrium to the left ventricle after the mitral valve opens. Additionally, mid-systolic murmurs typically occur in the middle phase of systole and do not last for the entire duration of the systole. Thus, the unique characteristic of a pansystolic murmur, being continuous throughout the entire systolic phase, makes it the correct answer in