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What is acyanotic heart disease?
Acyanotic heart disease is a group of heart conditions where blood with oxygen mixes with blood with little oxygen in the heart. This mixing is not enough to cause cyanosis, a symptom of not enough oxygen being delivered to tissues of the body, hence the name acyanotic heart disease. Created by Leslie Samuel.
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Why is it that when the de-oxygenated blood goes through the capillaries (gets oxygen), it becomes red?(4 votes)
When it binds oxygen the hemoglobin inside the red blood cells changes its light absorbing properties a little. That means you see a different rest of the spectrum i.e. another red compared to the dark red you see in CO2 loaded hemoglobin.(9 votes)
What about when you have a heart defect where you have 1 big ventricle? Or what about if you have transposition of the Great Vessels where the Aorta sends deoxygenated blood and the Pulmonary artery sends oxygenated blood to the lungs?
Would these be congenital, cyanotic heart diseases? And how would you treat someone with 1 big venticle or transposition of the Great Vessels? A heart transplant maybe?(1 vote)
Hypoplastic left heart syndrome (HLHS) is a cyanotic heart defect. There are two types of TGA: L-TGA (acyanotic defect) and D-TGA (cyanotic defect). HLHS and D-TGA require a communication in the heart (patent ductus arteriosus, patent foramen ovale / atrial septal defect, or ventricular septal defect) to allow mixing of oxygenated and deoxygenated blood. Without a communication that allows some oxygen to be pumped systemically the neonate will not survive. Cyanosis occurs in these two conditions because deoxygenated blood shunts through the communication from the right side of the heart to the left side of the heart and this deoxygenated blood is pumped systemically. Whereas in acyanotic heart defects oxygenated blood shunts from the left side of the heart to the right side of the heart and oxygenated blood simply passes through the lungs again. This is an inefficient system but the blood is fully oxygenated when it is pumped systemically.
A heart transplant is not the first choice for either of these conditions. Hypoplastic left heart syndrome involves a three-staged procedure (1) Norwood, (2) Glenn, (3) Fontan. D-TGA and L-TGA require different surgical procedures. Surgical correction for the cyanotic D-TGA simply involves switching the aorta and the pulmonary artery and re-anastomosing them to their correct ventricle. L-TGA is more complicated because not only are the aorta and pulmonary artery transposed but the left and right ventricle are as well. So deoxygenated blood enters the right atrium and flows into the morphologic 'left' ventricle (which is on the right side of the heart) and then into the pulmonary artery to the lungs. Oxygenated blood returns to the left atrium and flows into the morphologic 'right' ventricle (located on the left side of the heart) and then out the aorta to the body. A 'double switch' operation is performed. These individuals may be acyanotic but the right ventricle is not 'built' to pump blood at systemic pressures for a lifetime.(2 votes)
how does the oxygen turn red if you cant even see oxygen(0 votes)
If you've seen rust, you can understand that if you expose iron to areas with oxygen in moist areas, the iron will turn red. Iron oxide has a reddish color.
All red blood cells contain hemoglobin, which is a protein that contains iron. The red you're seeing is due to the oxygen interacting with the iron in hemoglobin.(3 votes)
Video transcript
Voiceover: So, I want to
talk about non cyanotic heart disease, but before
I do that, let's do a quick review of blood flow through the heart. So blood is coming back
from the rest of the body. As it's coming back, it is
going to be deoxygenated because the body was
using up all the oxygen and now it's sending the
blood back to the heart and it hardly has any oxygen in it, it's actually deoxygenated. So, this is coming back to
the right side of the heart, and from that right side,
as the heart is beating, it is going to send the
blood, the deoxygenated blood via these vessels and they're
going to go to the lungs. And it's a good thing that
they're going to the lungs, because here's what's
happening in the lungs: As it's passing through
these little vessels that we call pulmonary
capillaries, as it's passing through those
capillaries, it's going to pick up something
that's very important, and the thing it's going
to pick up is oxygen. And as it picks up that oxygen, you'll see that it kind of becomes
a brighter red color, a brightish red color;
before it was very dark, but as it's picking up
that oxygen it is changing color to where it's kind of bright red. And that blood is going to come back to the left side of the
heart and it's going to go through the left side of the heart and as the heart beats, it's going to send that oxygenated blood
now throughout the rest of the body, so this is
that blood, it's going through all of these
vessels and it's going throughout the body, which makes sense, it's delivering the oxygen to the body. Now, here's the thing: You
want to have this separation, you want the right side
to have your deoxygenated blood so that it can go through the lungs and then come back via this left side, so that can then go in its
oxygenated form to the body. Now, in individuals that
are born with non cyanotic heart disease, there is
some kind of a defect and I'm showing a defect
here, where there's a hole in the heart and that defect
allows for, of course, blood is going to pass through that hole. Even though that's not where
you want the blood to pass, if the hole is there and the
heart is beating, the muscle is contracting, it's going to send blood through that opening, but the question is, which direction is the
blood going to flow? And to answer that
question, let's just think logically about what's happening here: On the right side, this
side of the heart is beating and when the heart is
beating, this side is sending blood, it's not going a far distance, it's going right next door to the lungs, to come back to the
left side, but when the left side contracts, when
that beats, it's sending blood all throughout the body, it's going to the head, it's going to the neck, it's going to the arms and the legs and all throughout the body and this has to do significantly more work. You can see here that the muscle, here, is significantly thicker on the left side than we have on the right side. And as a result of that,
we're going to have significantly more pressure over here. And if you have more pressure over here, that is going to squeeze the blood through that opening and it's going to go from the left side to the right side. And that's exactly what we have with non cyanotic heart defect. It's a congenital disease; and congenital just means that that
individual is born with it, that causes blood to
shunt from left to right. Okay, so what's the problem here? Okay, so we have blood that's shunting from left to right because
we have a hole in the heart. And you often hear about
a hole in the heart and you wonder maybe
"That must be bad, right?" Well, let's think about what's happening, let's get back to that color that we were using before. What kind of blood do we
have over here on the left? Well, it's oxygenated blood. And if some of that squeezes through that little opening and
gets into the left side, okay, that oxygenated
blood is going to go back to the lungs and as it
goes back to the lungs with the rest of the blood, they're going to be picking up oxygen and then that's going to go back to the
right side of the heart, as we expect it to go, and then it's going to go to the body and some
of it might go back through. Is that a real problem? Well, usually when we have individuals with a small hole in the
heart, it's asymptomatic because what we're doing
is we're just sending oxygenated blood back to the lungs. That is not efficient, this
is not an efficient system. But, it's still functional,
the oxygen levels are going to be adequate
for normal function and, of course, the body
needs oxygen in order to do all of the things
that need to be done, so that it can have the
energy that it needs. And with this oxygenated
blood that's going back, we still end up with normal levels of oxygenation on this right side, so it's going to be asymptomatic. And it doesn't matter if
the hole is down here, or up here, the fact is
you have higher pressure on the left side and that
is going to always overpower the lower pressure on the right side. So you will always have
that left to right shunting; and that is in non cyanotic heart disease.