[Xaquake]

The murmur of mitral regurgitation is pansystolic and radiates to the left axilla.

Why does it radiate to the left axilla?

I'm thinking in terms of blood flowing back into the left atrium. The direction is such that I could understand if it was right axilla, but why the left?

 

[khanar]

Acute MR vz Chronic MR radiation

Nice anatomic thinking

The murmur of acute MR is not heard in the left axilla it radiates to the neck, top of head, and spine. Only when the case becomes chronic (so the left atrium dilates and changes direction) only then the murum can be heard in the left axilla.

Reference: Harrison's 17th edition

 

[khanar]

Loud murmu means radiation

Murmur radiation does not entirely depends on the direction of blood flow. It's simply an indication of the loudness of the murmur. So it's like a circular ripple of sounds around the lesion and it can be in any direction.

Loud MR murmurs (those with radiation) do not reflect severity.