Austin Flint murmur

In cardiology, an Austin Flint murmur is a mid-diastolic, low-pitched rumbling murmur which is best heard at the cardiac apex. It is associated with severe aortic regurgitation.

Mechanism
Echocardiography, conventional and colour flow doppler ultrasound, and cine nuclear magnetic resonance (cine NMR) imaging suggest the murmur is the result of (aortic regurgitant) flow impingement on the inner surface of the heart, i.e. the endocardium.

Classical description
Classically, it is described as being the result of mitral valve leaftlet displacement and turbulent mixing of antegrade mitral flow and retrograde aortic flow:

Displacement: The blood jets from the aortic regurgitation strike the anterior leaflet of the mitral valve, which often results in premature closure of the mitral leaflets.

Turbulance of the two columns of blood: Blood from left atrium to left ventricle and blood from aorta to left ventricle

Treatment
Aortic valve replacement may be necessary to correct the abnormality if symptomatic.

Eponym
It is named after the 19th century American physician Austin Flint (1812–1886).