well welcome to another MedCram lecture we could talk about a or decree Gurjit
ation we're gonna talk about the causes the pathophysiology clinical features
physical diagnosis treatment and when we should do surgery so specifically we're
talking about the aortic valve and what regurgitation simply means is that the
valve is incompetent and we get backflow and what are the causes of that and what
do we do about it and in terms of causes you can kind of
break it down into those less than 50 and those greater than 50 those less
than 50 that have a or tic insufficiency are usually due to post inflammatory
those after the age of 50 have usually to do with aortic root dilatation and so
specifically the post inflammatory the type of things that you want to think
about our rheumatic heart disease or our h d rheumatic heart disease infectious
endocarditis think about syphilis and then in terms of a otic root dilatation
think about other things think about age-related or the other one
to think about is more fans Marfan syndrome as you may know is where
they're very tall they've got long legs long legs and long arms and they can get
Eric root dilatation in terms of other things to think about is think about
lupus or SLE and this thing called ankylosing spondylitis and callosum
spinal eyes that's where they get the bamboo spine okay so the pathophysiology
of this is that this valve the aortic valve becomes leaky and blood goes back
into the left ventricle and this occurs of course during diastole
so it's diastolic that means between s2 and then at the beginning of s1 again as
a result of that it's going to cause the left ventricle to become bigger because
blood is coming back in it's going to increase the preload and as a result of
the fact that it's pumping more blood you're also they get hypertrophy so
you see it's in diastole you got to get a murmur diastolic murmur okay that
diastolic murmur because it's on the left side anything that increases the
left side is going to cause the diastolic murmur to get bigger so what
are those things that causes the left side to get bigger would be any kind of
straining okay anything that increases afterload and what's going to cause it
to get smaller the the murmur to get smaller well anything that decreases the
left side of the heart so that would be a valsalva or anything that causes
dilation of the peripheral vasculature that would be like amyl nitrate now as
you may recall this a Horta kind of works as what the german word is like a
wind Kessel basically it expands during systole and then as diastole occurs it
contracts as it contracts the kind of ends ends up like being a pump by itself
pumping the blood forward however in a or decree Gurjit ation instead of that
blood going forward the blood goes backwards and backwards here into the
left ventricle so you're gonna get left ventricular hypertrophy and you're gonna
get an increase in the left ventricular end-diastolic volume now in addition to
that because during diastole you've got all this blood coming back into the left
ventricle you're gonna see a low diastolic blood pressure and because
there's more blood in the left ventricle right before systole more blood is going
to be ejected out and so therefore you're going to see an increase in
systolic blood pressure this is known as a increase in the pulse pressure which
sets up some pretty interesting physical exam findings so in other words when you
take the blood pressure and you take the systolic over the diastolic you're going
to see that the difference between those two pressures is going to go up so let's
quickly talk about some of the clinical features that you might see as we
mentioned you're going to see in you're going to see LVH left ventricular
hypertrophy or a left ventricular end-diastolic
vol which is increased the other thing that you might see is syncope just like
we saw an aortic stenosis however there's a couple of reasons why you
might see that here the first is that if the diastolic pressure is so low that
you can't maintain an adequate perfusion you're gonna see syncope but the other
thing that you're gonna see here and this is a little bit more subtle as you
might see angina now why is that you think you should know is that the
coronaries come off of this area in the aorta and what drives blood pressure or
what drives perfusion in these very important coronary arteries is actually
the diastolic blood pressure okay because flow occurs mainly through the
time period of diastole and so during diastole is when you're gonna get this
pressure here pushing blood through the arteries to the myocardium if your
diastolic blood pressure is low because it's instead of going into the
coronaries it's going back here into the left ventricle you're gonna get a
decreased coronary artery perfusion pressure and as a result you're gonna
get angina now one thing I will say is that when you look at systole through
the cardiac cycle from one period to the next period let's say we start at s1 s2
is fairly short after it and then you've got diastole so this is systole and this
is diastole okay now where is this regurgitant flow occurring it's
occurring between s2 and the next s 1 which is diastole something that you may
not know is that when you speed up the heart rate this period of time between
s1 and s2 doesn't really change much it stays the same what does change is the
time period of diastole it gets shorter and shorter to allow for a faster heart
rate the point is is that as the heart rate speeds up diastole becomes shorter
and shorter and therefore the time for regurgitation becomes less and less so
as a result of this you usually see that tachycardia is well tolerated
okay so tachycardia is well tolerated in a or t'k insufficiency okay
let's talk about physical diagnosis what you'll see is because this is getting
larger you'll see the apical impulse is going to be displaced downward and to
the left and then the actual diastolic murmur is going to be a high-pitched
murmur heard at the left sternal border and it's going to actually be heard
quite well if you have the patient lean forward so if they're sitting on a table
have them lean forward and then place the stethoscope there that'll bring that
murmur closer to the chest wall and you'll be able to hear it much better
now an interesting thing that occurs is something called the Austin Flint murmur
it's actually one guy just with two different names
Austin Flint is the murmur that occurs when blood goes back across the aortic
valve and because it's flowing in here it tends to keep this mitral valve
closed or at least almost closed now remember that blood is supposed to be
going from the left atrium into the left ventricle during diastole and if this
blood from the aorta is coming in and closing that valve or at least I try and
attempt to to close that valve you're gonna get a functional a or Dart mitral
stenosis that is the murmur of the Austin Flint and that's a rumbling okay
that's a rumbling sound so you might hear a high-pitched murmur and then a
rumbling throughout diastole that could be an Austin Flint murmur that's
associated with an aortic regurgitation murmur that's the from the vibrations
now we talked before about this increased pulse pressure so that the
systolic blood pressure is high and the diastolic is low that it causes a change
or a pulse pressure that's gonna make the pulse pressure go up from our
equation as a result of this you'll see that that people's pulses are very
bounding and they're very large and amplitude and there's a number of things
that are found on physical exam you may want to know some of the names but
they're not essential so this is known as a corridor pulse
okay if you've listened to this or if you feel this in the femoral area it's
known as a pistol shot okay that's the femoral if you hear a diastolic bruit
over the femoral area so a diastolic bruit that's known as the Rozier sign D
you are oh z IE z de rozier sign okay now if you see a bobbing head that's
known as doom you say sign de space M u SS et and interesting they used to think
that Abraham Lincoln had Marfan's disease because they felt number one he
was very tall and also that whenever they looked at pictures of him they
found that his head was kind of a blur and they needed to take long exposures
back in those days and because of this Dumas a sign that he must have had from
an aortic regurgitation that they felt that this was proof that he had Marfan's
disease I don't I think the jury was out on that they don't really know if he did
or not it or maybe the photographer was just a bit too shaky anyhow just a
little way to put all that together another thing is quickies pulse quickies
pulse is when you look at the nail bed of your fingers and you see that there's
a blushing and blanching so these are all signs of aortic insufficiency of
course you're going to order an echocardiogram to make the final
diagnosis on that but interesting nonetheless so again how are you going
to make the diagnosis and today's day and age it's going to be echocardiogram
they're gonna be able to look at the valve they'll be able to tell you how
much regurgitation there is and some other things that might lead you to
think is a chest x-ray what are you gonna see on a chest x-ray well if that
if it's severe you'll see this left ventricle and large you will also see
pulmonary vascular congestion possibly obviously a cardiologist before surgery
is going to do a right heart cath where they actually float in a catheter into
this area they can release contrast and they can see how much is going back and
forth and they can actually calculate the regurgitant of all
in terms of treatment you're gonna want to make sure most the blood is going out
so the way you do that is with loop diuretics to get rid of some of this
excess fluid and then you want to reduce afterload and that would be with
something like nitrates or hydralazine you don't want to use things like beta
blockers that slow the heart rate down because remember if you slow the heart
rate down it's going to increase the time in diastole this is going to
increase regurgitation and it may steal away some of your perfusion from your
coronary arteries you actually see a reversal of flow in the coronary as if
if the regurgitation is that bad then your patients will start having angina
okay so surgery when you do surgery basically when you start to see left
ventricular decompensation so when you see the ejection fraction going down
when you see more congestive heart failure it's really a cardiologist call
but that's when you get referral and of course you're going to get an aortic
valve replacement you can either get a bio prosthetic valve which does not
require anticoagulation or you'll get a mechanical valve which does require
anticoagulation thank you for joining us
you