Murmur vs. Bruit?

[GermPhobe]

Can someone explain the difference in sound between a murmur and a bruit? I've had two patients recently who I thought had bruits. But other nurses had charted murmurs. I thought a murmur was a kind of "soft" heart sound--a blurring of the "lub" and "dub." The two patients in question a had distinct, high-pitched, rhythmic "hmmm, hummm, hummm." So what was I hearing????

THANKS!

[augigi, CNS]

Depends what and where you are listening to?

A bruit is generally a sound made by a non-cardiac vessel, while a murmur is made by abnormal flow through a cardiac valve (either accelerated by a narrowing, or backflowing through an incompetent valve).

Hope that helps, tell me if it was too basic.

[Indy, LPN, LVN]

Depends what and where you are listening to?

A bruit is generally a sound made by a non-cardiac vessel, while a murmur is made by abnormal flow through a cardiac valve (either accelerated by a narrowing, or backflowing through an incompetent valve).

Hope that helps, tell me if it was too basic.

A bruit is not usually heard over the part of the chest where you hear heart sounds. It can be heard over the carotids, femoral arteries, A-V fistula sites, etc. A bruit sounds like a washing machine to me. (Ok, a really small washing machine...) A murmur is abnormal noises made by heart valves. So a bruit over the heart would be a... bad thing, since other than the AV fistula, it's not a sound you want to hear in a big vessel. Either something's really blocked the vessel, or there's a pseudoaneurysm going on. Both of which could happen to the aorta near the heart, but golly. I think if I heard that I'd have several other people in there listening just to make sure.

Hope that helps.

Woops. Just realized I quoted the wrong post. Eep!

[GermPhobe]

Depends what and where you are listening to?

A bruit is generally a sound made by a non-cardiac vessel, while a murmur is made by abnormal flow through a cardiac valve

Hope that helps, tell me if it was too basic.

A bit too basic, LOL. I know the physiological difference between the two--but I'm wondering how they sound different. In one case, the "murmur" was so loud it could be heard while I was auscultating bowel sounds! Of course it was INCREDIBLY loud over the heart. But it was NOT a softening of lub-dub. It was simply a very LOUD, pulsatile "hmm, hmm, hmm." I was thinking it could be an aortic aneurysm?

How LOUD can a murmur get?

[augigi, CNS]

Sorry. The loudness depends on the severity of the underlying pathological condition. That is like asking "how long is a piece of string?" - there is no answer to that. I have definitely heard murmurs which were "whooshing", loud noises and not "clicks".

Again, as to your initial question, if it is of cardiac origin it's a murmur, no matter how it sounds. An aortic aneurysm doesn't usually cause a loud bruit, as there is generally aortic widening at the weak site, rather than narrowing which would cause the rushing sound caused by acceleration of the blood.

[augigi, CNS]

PS: What was the patients' history - anything that would support the diagnosis of murmur?

[GermPhobe]

Yes, he had a known murmur. But, being a new nurse, I'd only heard very quiet murmurs. HOLY COW that one was loud--and sounded like the bruit that was diagnosed on another patient I'd dealt with. Putting two and two together, I concluded this murmur must be "more" than just a murmur. Perhaps I should put the math book away, LOL.

[augigi, CNS]

Don't worry, until you listen to hundreds they all sound like a washing machine in varying states of disrepair!! I used to nod along at nursing school when I couldn't tell what the heck they were hearing cos it sure wasn't what I was hearing!

I go on the theory that if it's quiet enough that I can hardly work out what it is, it isn't going to be much of a problem for them. Generally when someone is sick from a cardiac condition, there aint no mistaking the presence and type of murmur!