Step I bicuspid aortic valve

[viper]

q-bank says that bicuspid aortic valve causes an immediate diastolic murmur. Can someone please explain why its a diastolic murmur and not a systolic murmur? I was thinking this is similar to aortic stenosis (which is what it says), but that is a systolic murmur.

Thanks,

 

[bigfrank]

Hey there, this Emedicine article explains this pretty well. In short, the murmur is usually a systolic ejection click, consistent with your thinking (bicuspid valves can predispose to eventual stenosis leading to systolic murmurs).

On the other hand, however, bicuspid valves can be associated with aortic root dilation (which may cause a diastolic murmur). So I can see it both ways.

P.S. Good association here with coarctation of aorta or XO syndrome.

 

[ucbdancn00]

q-bank says that bicuspid aortic valve causes an immediate diastolic murmur. Can someone please explain why its a diastolic murmur and not a systolic murmur? I was thinking this is similar to aortic stenosis (which is what it says), but that is a systolic murmur.

Thanks,

you might want to think of it like this

AO stenosis--> blockage of the valve (3 valve cusps)--> problems with flow while trying to contract--> systolic murmur as blood gets through any tiny openings

bicuspid AO valve--> missing one of the cusps--> a more "leaky" valve
-->blood can more easily get back through during "diastole" (not as much of a problem pushing blood through during systole)--> diastolic murmur.

The eventual calcification of the AO valve is what will produce AO stenosis and give you your "crescendo-decrescendo" systolic murmur. Most cases of AO stenosis, are due to calcified bicuspid AO valves.

hope this helps

ucb

 

[divinemsm]

you might want to think of it like this

AO stenosis--> blockage of the valve (3 valve cusps)--> problems with flow while trying to contract--> systolic murmur as blood gets through any tiny openings

bicuspid AO valve--> missing one of the cusps--> a more "leaky" valve
-->blood can more easily get back through during "diastole" (not as much of a problem pushing blood through during systole)--> diastolic murmur.

The eventual calcification of the AO valve is what will produce AO stenosis and give you your "crescendo-decrescendo" systolic murmur. Most cases of AO stenosis, are due to calcified bicuspid AO valves.

hope this helps

ucb

...so can this bicuspid aortic valve be considered the " same as " ( so to speak ) as aortic insufficiency /regurgitation ? ..then I would get the rationale for it being a diastolic murmur...thanks!

 

[bigfrank]

...so can this bicuspid aortic valve be considered the " same as " ( so to speak ) as aortic insufficiency /regurgitation ? ..then I would get the rationale for it being a diastolic murmur...thanks!

That would be the only way to explain the diastolic murmur. By definition, a diastolic murmur is going to happen due to some sort of valvular incompetency.

 

[Ramoray]

this question was asked before but from all the sources i have seen i have never heard diastolic murmor being assoc with bicus. aortic valve. I am not saying sources dont exist and it doesnt happen, but at our level forsure and even general medicine you think systolic murmor with bicuspid aortic valve. you would never have a stricly diastolic murmor with bicu. aortic valve from what i can imagine. I believe its a qbank bad explanation. i would just remember systolic.

 

[bigfrank]

this question was asked before but from all the sources i have seen i have never heard diastolic murmor being assoc with bicus. aortic valve. I am not saying sources dont exist and it doesnt happen, but at our level forsure and even general medicine you think systolic murmor with bicuspid aortic valve. you would never have a stricly diastolic murmor with bicu. aortic valve from what i can imagine. I believe its a qbank bad explanation. i would just remember systolic.

Rammie, I agree with you here. The Emedicine article I linked above supports this and states that the most common murmur assoc'd with Bicuspid aortic valve is systolic. But it can also be assoc'd with aortic root dilation, which would explain a diastolic murmur.

Noone get too stressed about this. The TYPES of questions you'll be asked will NOT make you diagnosis bicuspid aortic valve based on heart sounds. You might need to apply pathophysiololgical concepts, but I wouldn't get too hung up on the Syst. vs. Diast. murmur.

 

[Idiopathic]

The systolic murmur usually occurs later in life, as the valve calcifies and cant open or close properly. Early on, due to the poor structure of the valve, insufficiency would be more likely.

 

[Ramoray]

The systolic murmur usually occurs later in life, as the valve calcifies and cant open or close properly. Early on, due to the poor structure of the valve, insufficiency would be more likely.

I konw its a silly topic but i have to disagree as i am pretty positive the bicuspid valve works fine for awhile but just calcifies earlier than a normal one normally does and the progression would be -normal valve function--> systolic murmurdue to stenosis calcified bicusp valve---> folllowed maybe later by a diastolic murmor due to aortic root dilation which would only occur years following a stenosed aortic valve. and even at this point u would have some mixed type. anyway doesnt even matter. just my thoughts you very well could be right.