The murmur of Austin flint is has become an immortal cardiac auscultatory sign even in this era of hi tech cardiology. This is our humble tribute to the physicians of those time , who were blessed with meticulous observatory and auditory skills .
In the year 1859 , Austin flint was able to delineate the hemodynamics of Aortic regurgitation . , ( 50 years before the invention of ECG and X ray , 125 years before the echocardiography was discovered )
It was his suggestion , in severe aortic regurgitation , as the blood leaks back in to LV, the regurgitant jet mechanically interferes with mitral valve opening and hence a functional obstruction to mitral inflow .This generates a mid and late diastolic murmur from the mitral valve which is heard well in the mitral area.
This was confirmed 100 years later as anterior mitral leaflet flutter by echocardiography in severe AR.
We have since improved our understanding about the mechanism of of mitral MDM in AR
- It is also attributable to the raise in LVEDP and hence mitral valve tend to float early and assume a relatively closed position.(Resultant functional MV narrowing )
- One more mechanism that could contribute to Austin flint murmur is the diastolic mitral regurgitation that occur in some cases of acute severe aortic regurgitation .
Anterior mitral leaflet flutter is the classical echo correlate of Austin flint murmur.
Differentiation from organic Mitral stenosis
In mitral stenosis following are present .
- MDM with presystolic accentuation
- Opening snap
- Loud S 1
Austin flints original article Flint A. On cardiac murmurs. Am J Med Sci. 1862; 44:29-54