what is IVDA.
on page 231 of FA, what's the importance of knowing you can hear "Flow murmur" under aortic area and pulmonic area. what kind of flow murmur are they talking about.
Turbulence is a condition where the flow is not smooth and layered (not laminar, laminar means layered; turbulence is the opposite). What determines if flow is laminar or turbulent? Look up reynold's number, but anything that alters has the potential to create a murmur, assuming the magnitude is great enough.
So, what happens is that when there is a valvular pathology? There is TURBULENT flow after the valve. Now, when you hear turbulence, you call it a MURMUR.
MURMUR=BLOOD FLOW THAT IS NOT SMOOTH.
Now, picture aortic stenosis (rf). What happens? You have a valve with a small orifice (opening). Now picture the blood trying to get past the small hole. It creates turbulence, which we said would be heard as a murmur.
What about a murmur that is heard over the aortic area that is not due to an intrinsic defect in the valve? When would you hear this? Say you have an anemic pt who has increased CO to compensate for the decreased total o2 content? You would have greater FLOW over the aortic valve, leading to a FLOW murmur. Remember Reynold's number? Well, velocity is one of the paramaters, where increased velocity would increase chance for turbulence; now, think of viscosity-anemics have decreased hematocrit and therefore less viscous blood
decreased viscosity-->more chance for turbulence. So increased VELocity and decreased VISCosity lead to greater chance for a FLOW MURMUR. There are other conditions that could do this.
I hope this makes sense.