Austin Flint Murmur: Mid diastolic, low pitch rumble murmur heard best at the apex
Occurs in Aortic Regurgitation as a result of the vibration of the anterior leaflet of the mitral valve due to the regurgitant jets from the left atrium and aorta. The striking of these regurgitant jets often cause the premature closure of the mitral leaflets, commonly mistaken for mitral stenosis.
- The absence of an opening snap and loud S1 distinguishes the pure aortic regurgitation of an Austin flint murmur from that of mitral stenosis
- An ECG may show a sinus rhythm with left ventricular hypertrophy, left axis deviation and prolonged PR interval.
1862 – Flint published his extremely detailed account ‘On Cardiac Murmurs‘ and in depth analysis of cardiac murmurs in the setting of valvular heart disease. He described, for the first time, a presystolic murmur in the setting of aortic regurgitation.
The murmur is oftener rough than soft. The roughness is often peculiar. It is a blubbering sound, resembling that produced by throwing the lips or the tongue into vibration with the breath of respiration[On Cardiac Murmurs 1862 p50]
Two patients, both with signs of with aortic regurgitation and aortic stenosis, and with the described distinct presystolic murmur at the apex were found to have normal mitral valves without gross pathology at postmortem.
“In some cases in which free aortic regurgitation exists, the left ventricle becoming filled before the auricles contract, the mitral curtains are floated out and the valve closed when the mitral current takes place, and, under the circumstance, the murmur may be produced by the current just named, although no mitral lesion exists.[On Cardiac Murmurs 1862 p53]
- Austin Flint (1812-1886)
- Flint A. A Practical Treatise on the Diagnosis, Pathology and Treatment of Diseases of the Heart. Blanchard and Lea, 1859.
- Flint A. On Cardiac Murmurs. American Journal of the Medical Sciences. 1862;44:29-54.