Hypertrophy of the Heart
Concentric (thick) HPY’d heart vs. Dilated HPY heart: 2 different etiologies, and they involve
work. It requires a lot of work to contract and push blood thru a stenotic aortic valve, or
increased TPR from HTN. These will cause an increased afterload = concentric HPY.
If you have a valvular problem, and have excess volume of blood in the ventricles – increased
preload = increased work. Therefore, the frank starling goes into effect b/c stretching and
increasing preload in there, and you have to work harder to increase the force of contraction –
this produces dilated HPY. Therefore, concentric HPY = afterload problem; dilated HPY =
volume overload = preload problem (increased volume)
Heart sounds –
S1 heart sound = beginning of Systole = mitral and tricuspids close (mitral closes before the
tricuspid b/c higher pressures)
S2 heart sound = beginning of Diastole = pulmonic and aortic close (variation with respiration –
as diaphragm goes down they increase the intrathoracic pressure. Blood is being sucked into
the right side of the heart, and the pulmonic valve will close later than the aortic valve. So, the
second heart sound has a variation with inspiration – the P2 separates away from A2 b/c more
blood coming into the right heart, so the valve closes a little bit later.
S3 heart sound = normal under 35 y/o’s. After that, it is pathologic. S1 = beginning of systole
and S2 = beginning of diastole; obviously, S3 = early diastole. S3 is due to blood, in early
diastole, going into a chamber that is volume overloaded. So, blood from the left atrium is
going into overloaded chamber, causing turbulence, which is the S3 heart sound. Only hear S3
heart sound in volume overloaded chamber. It could be from LHF (left ventricle overloaded)
or RHF (right vent overloaded), so there are left sided S3’s and right sided S3’s – it means
volume overload in the chamber. Analogy: rivers going into ocean – leads to turbulence (ocean
is the ventricle with a lot of fluid in it and the river is the blood coming in during diastole; the
river hits this large mass of fluid in the ventricle, causing turbulence and an S3 heart sound).
S4 heart sound = late diastole – this is when the atrium is contracting and you get the last bit of
blood out of the atrium into the ventricles, leading to S4 sound. S4’s occur if there is a problem
with compliance. Compliance is a filling term.
So, when talking about compliance, referring it’s ability to fill the ventricle. The left atrium is
contracting, trying to get blood into a thick ventricle; the ventricle is noncompliant, and
therefore resistance will occur. This will create a vibration, leading to an S4 heart sound. An S4
heart sound is due to a problem with compliance. The left atrium is encountering a problem in
putting blood in late diastole into the left ventricle and it doesn’t want to fill up anymore. This
could be due to 2 reasons: (1) b/c it’s hypertrophied (it doesn’t want to fill anymore–restricting
filling up) or (2) it’s already filled up and has to put more blood in an already overfilled
chamber. Summary: Slides:
Vol overloaded? No S3. So can it have an S4? Yes.
If you have HTN, which type of heart will you have? Concentric HPY. So, in HTN, which type of
heart sound will you have? S4.
Vol overloaded? Yes. So can it have an S3? Yes; can it also have an S4? Yes. Why can it also have
an S4? B/c it can’t fill up anymore. Analogy: turkey dinner – all filled up, but always room for
desert – lil vibration that occurs when it fills is an S4 heart sound. So you have both S3 and S4
heart sound = gallop rhythm (they have S1, 2, 3, and 4).
How do you know if its from the left or right? It is breathing. When you breath in, you are
sucking blood to the right side of the heart. All right sided heart murmurs and abnormal heart
sounds (ie S3, S4) increase in intensity on inspiration – this is more obvious b/c there is more
blood in there, and it emphasizes those abnormal sounds. Prob get them on expiration with
positive intrathoracic pressures that are helping the left ventricle push blood out of the heart –
this is when abnormal heart sounds and abnormal murmurs will increase in intensity on
expiration. So, all you have to do is figure out that there is an S3 heart sound. *****Then, you
have to figure out which side it is coming from. Louder on expiration, therefore its from the
Example: essential HTN = left;
Mitral regurg = right;
and Mitral stenosis = middle.
Stenosis = prob in opening, that is when the valve is opening, and that is when the murmur
Regurgitation = prob in closing the valve, that is when the valve is closing, and that is when the
Need to know where valves are heard best – right 2 ICS (aortic valve), left 2 ICS (pulmonic),
left parasternal border (tricuspid), apex (mitral) – this isn’t necessarily where the valve is, but
where the noise is heard the best.
Who is opening in systole = aortic and pulmonic valves = therefore, murmurs of aortic stenosis
and pulmonic stenosis are occurring in systole. Thi