Clinical Presentation of Congenital Heart Disease: Congestive Heart Failure by Michael Freed, MD
Clinical Presentation of Congenital Heart Disease: Congestive Heart Failure by Michael Freed, MD
Dr. Michael Freed reviews the clinical presentation of congestive heart failure in the newborn period.
Direct links to chapters:
2:14 Chapter 2 Fetal Development
4:29 Chapter 3 Structural Heart Disease
Initial publication: August 22, 2016.
Last reviewed: October 30, 2019.
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Content
26 -> Clinical Presentation of Congenital Heart
Disease in the First Week of Life: Congestive
31.741 -> Heart Failure, by Dr. Michael Freed.
39.62 -> My name is Michael Freed and I'm a Pediatric
Cardiologist at Boston Children's Hospital
43.98 -> and at Harvard Medical School.
46.09 -> And I want to spend a little time today talking
about congenital heart disease in the newborn
50.39 -> period.
52.82 -> Introduction.
55.25 -> Children come in in the first week of life.
56.65 -> They present in one of four ways.
59.11 -> With a heart murmur, with an arrhythmia, congestive
heart failure, or with cyanosis.
67.38 -> So let's talk about congestive heart failure.
70.84 -> Congestive heart failure is an inability of
the heart to do the work that's required,
79.45 -> and the signs and symptoms that come because
of that inability.
86.61 -> There are two conceptual reasons why you might
have difficulty.
91.36 -> The first is that there is something wrong
with the heart muscle.
94.95 -> You have a normal amount of work.
97.31 -> But somehow the muscle just isn't strong enough
to do the work.
100.979 -> The second is that you have a normal muscle,
but you've put too much of a workload on it.
108.2 -> So if there was a weight on the table in front
of me, if there was a 5 pound weight and I
113.17 -> couldn't do it, there's something wrong with
me.
115.479 -> If there's 1,000 pound weight, I just can't
do a 1,000 pound weight.
120.56 -> If you looked around our ward, I think you
would say that the structural problem, too
126.87 -> much work with normal muscle is much more
common.
131.299 -> I'm not so sure that's the case.
134.86 -> Fetal Development.
136.89 -> I think that almost all of these are genetic
defects.
143.92 -> And I suspect there are just as many genetic
defects in the mitochondria and energy transport
149.04 -> systems as there are causing structural heart
disease, but we just don't see them.
154.819 -> Where are they?
155.819 -> Well, I think they don't survive fetal life.
159.73 -> I think that you can be born without kidneys,
you can be born without lungs, you can be
165.819 -> born without a large part of your brain.
168.37 -> But once you have an embryo that's more than
four cells thick, you need some way of getting
175.37 -> nutrients inside to the cells and get waste
products out.
180.03 -> So once an embryo is more than four cells
thick, you need some type of circulatory system.
186.65 -> And in fact, in the human, there's a primitive
straight tube that develops by 27 days after
193.22 -> conception that's actually doing the work.
196.349 -> And if there's something wrong with that tube,
if there's something wrong with the muscle,
200.36 -> they just don't survive fetal life.
203.1 -> So I think a lot of first trimester abortions
may very well be heart muscle problems that
208.55 -> we're not seeing.
210.3 -> And the rest of fetal life selects out for
those, leaving just the ones with normal muscles,
216.73 -> but structural problems.
218.73 -> And the corollary to that is that the things
that we're seeing at birth are in fact things
224.47 -> that work in utero.
226.56 -> Otherwise, they wouldn't survive fetal life.
230.22 -> And what happens is that I think that the
fact that the circulation is arranged in parallel
236.12 -> rather than series allows a whole group of
very complicated diseases that work in the
243.739 -> newborn period, but once you go into that
in the series circulation, don't work after
249.19 -> you're born.
252.18 -> So I think this presentation of babies in
the first week of life are kids that worked
257.89 -> in utero, but don't work when they're born.
260.239 -> And I think there's a comparable group that
doesn't work in utero that we're not seeing,
265.27 -> and a lot of those have muscle problems.
269.41 -> Structural Heart Disease.
272.47 -> So if we have a baby with congestive heart
failure-- he doesn't have a muscle problem,
277.9 -> he's got some structural problem, too much
work for a normal muscle.
281.63 -> And remember, we said the work of the heart
is pressure and volume, so there must be either
287.24 -> too much pressure work or too much volume
work.
291.79 -> If you look at the first month of life, I
think that most kids who come in would be
296.65 -> too much volume work.
299.5 -> Ventricular septal defects, single ventricles
without pulmonary stenosis, truncus arteriosus,
311.479 -> the whole variety of things.
314.97 -> But we don't see those in the first week of
life.
318.15 -> In the first week of life the pulmonary vascular
resistance is still quite high.
323.87 -> And it prevents enough of a left-to-right
shunt through the VSD, or the single ventricle,
329.33 -> or the truncus to give enough of a volume
overload to cause congestive heart failure.
334.43 -> So if our talk is heart failure in the first
week of life, which is what we've started
339.139 -> the premise, then we're dealing not with muscle
disease, not with volume overload, but just
345.66 -> pressure overload lesions.
348.93 -> And if you look at the pressure overload lesions,
aortic stenosis, pulmonary stenosis, coarctation,
367.75 -> and hypoplastic left heart syndrome.
372.09 -> And I'm going to make it even easier.
374.16 -> Pulmonary stenosis doesn't fit here.
375.509 -> If we're talking about heart failure, tachypnea,
tachycardia, not feeding very well, sweating--
381.08 -> that's not the way pulmonary stenosis presents.
384.86 -> If you look at pulmonary stenosis, these kids
have severe right ventricular outflow tract
390.19 -> obstruction.
391.48 -> The right ventricle has to generate a higher
pressure to pump blood out.
396.69 -> And if it starts having difficulty generating
that higher pressure, by Starling's Law, it
401.85 -> increases preload.
406.43 -> If you increase the preload in the ventricle,
the atrial pressure goes up.
410.93 -> And in the newborn period, if the right atrial
pressure exceeds the left atrial pressure,
416.389 -> you start shunting right-to-left and you end
up with cyanosis.
420.94 -> So kids with severe right ventricular outflow
tract obstruction from pulmonary stenosis
425.74 -> present with cyanosis, not with congestive
heart failure.
429.65 -> So now we're essentially down to three diseases
in our differential diagnosis of heart failure
437.35 -> in the newborn period.
440.24 -> And how can we tell these apart?
442.57 -> Well, coarctation-- now, the difference in
pulses or blood pressure should work.
450.05 -> That is, before the ductus closes they're
not sick.
454.139 -> But if these kids are sick, the ductus must
have closed and now they must have a pressure
458.93 -> gradient.
459.93 -> So just feeling pulses or measuring pre- and
post-ductal blood pressures should diagnose
466.37 -> coarctation for you.
468.69 -> In neonates with coarctation of the aorta,
the strength of the pulses in the lower extremity
474.15 -> will be reduced or absent in comparison to
the pulses in the upper extremity.
479.66 -> Pre- and post-ductal blood pressure examination
will reveal a discrepancy between the right
485.12 -> arm-- which is pre-ductal-- and the leg--
which is post-ductal-- blood pressures, with
490.181 -> a higher systolic blood pressure in the right
arm when compared to the legs.
495.18 -> Typically, a discrepancy of greater than 20
millimeters of mercury in the systolic pressure
500.52 -> measurement is considered significant and
should prompt further workup for coarctation.
506.81 -> To separate out aortic stenosis from hypoplastic
left heart syndrome get an electrocardiogram.
512.829 -> These kids have LVH.
518.07 -> These kids have no LV.
524.039 -> And that's the differential diagnosis of heart
failure in the newborn.
527.79 -> This concludes our video on Clinical Presentation
of Congenital Heart Disease in the First Week
533.35 -> of Life: Congestive Heart Failure.
536.54 -> Thank you.
538.33 -> Please help us improve the content by providing
us with some feedback.
Source: https://www.youtube.com/watch?v=3izIHXUlS6U