The Murmur
The murmur of Mitral Regurgitation can be of various qualities and many adjectives have been used in describing the murmur.  Best heard at the Apex of the heart, the murmur can  vary in loudness depending on the degree of the insufficiency and it can radiate to the left sternal edge and/or to the midaxilla and back. Words like “Rough, harsh, blowing” are often used, but in some patients the sound can also be of more musical quality.

Timing:

Chronic Mitral Regurgitation is holoystolic, starting immediately after/into the first heart sound. The murmur may peak in early, late or mid-systole.

Devation to this are found in:

Mitral Valve Prolapse (MVP) w/Mitral Regurgitation:

Regurgitation may or may not occur with MVP.  If regurgitation is present, this develops from a end-systolic murmur (end-cresendo) to encompass more and more of systole as it develops.

Acute Severe Mitral Regurgitation:

The pressure gradient between Left Ventricle and Left Atrium is reduced in later systole, resulting in varying degrees of end-systolic murmur. Most often you will find that the murmur will weaken and may be absent in the latter part of the systole.

Papillary muscle dysfunction:

Associated with ischemia/infarction, MR may occur. Depending on the degree of impairment of the papillary muscle contraction of the ventricular wall, a murmur may be heart in mid to late systole.