Austin flint murmur is a: September 2009
**Core Concept**
Austin Flint murmur is a mid-diastolic rumble heard best at the cardiac apex in patients with severe aortic regurgitation. It is caused by the regurgitant aortic jet hitting the anterior leaflet of the mitral valve, resulting in a vibration that produces the murmur.
**Why the Correct Answer is Right**
The murmur is thought to be caused by the regurgitant aortic jet hitting the anterior leaflet of the mitral valve, resulting in a vibration that produces the murmur. This vibration is transmitted to the chest wall, creating the mid-diastolic rumble heard best at the cardiac apex. The murmur is often associated with severe aortic regurgitation and can be a sign of impending heart failure.
**Why Each Wrong Option is Incorrect**
* **Option A:** Not a characteristic of Austin Flint murmur, which is a mid-diastolic rumble, not a systolic murmur.
* **Option B:** Not the cause of Austin Flint murmur, which is attributed to the regurgitant aortic jet hitting the mitral valve, not the tricuspid valve.
* **Option D:** Not a characteristic of Austin Flint murmur, which is a mid-diastolic rumble, not a pansystolic murmur.
**Clinical Pearl / High-Yield Fact**
Austin Flint murmur is often associated with severe aortic regurgitation and can be a sign of impending heart failure. It is essential to recognize this murmur and investigate the underlying cause of aortic regurgitation to prevent complications.
**Correct Answer: C. Austin Flint murmur is a mid-diastolic rumble heard best at the cardiac apex in patients with severe aortic regurgitation.**