Which murmur in mitral regurgitation is recognized as radiating to the axilla?

In mitral regurgitation, a holosystolic murmur is produced due to the backflow of blood from the left ventricle into the left atrium during systole. This murmur typically begins with the first heart sound (S1) and extends all the way to the second heart sound (S2), which is why it is described as "holosystolic."

The distinctive feature of this murmur is its radiation pattern—specifically, it commonly radiates to the left axilla. This is a classic teaching point in cardiology, as it helps clinicians identify and confirm the presence of mitral regurgitation during auscultation. The pathophysiological basis for this is that the turbulent flow from the regurgitant jet moves posteriorly towards the left atrium and can be heard at the left axilla due to the anatomy and positioning of the structures involved.

In contrast, systolic ejection murmurs are typically associated with blood flow across the aortic or pulmonary valves and do not have the same pattern of radiation. Diastolic murmurs are commonly associated with conditions like aortic regurgitation or mitral stenosis, and they do not present in the same way as the holosyst