This is a tutorial on the heart and some of the major vessels that lead to the heart and
from the heart.
So here, we're looking at an anterior view of the chest with the thoracic cage and the
muscles dissected away.
So you can see the heart sitting centrally in the mediastinum, which is this central
compartment of the chest separating the pleural cavities on either side.
The heart, as you can see, is angled to the left.
So the apex of the heart is angled down into the left.
You can see it sitting on top of the diaphragm, which is this flat muscle here.
So in the anatomical position, which we're looking at now, the heart has several surfaces.
The surface that's in contact with the diaphragm, the inferior surface of the heart is known
as the diaphragmatic surface.
This right side of the heart which is in contact with the right lung is called the right pulmonary
surface.
Conversely, the left side which is in contact with the left lung is called the left pulmonary
surface.
The anterior surface of the heart, which is in contact with the sternum is called the
costosternal surface.
The back of the heart, which you can't see in this particular view is known as the base
of the heart.
This point here is the apex of the heart.
So it's important to note the orientation of the heart in this position.
So when you're looking at it from this view, front on, you're seeing mostly the right side
of the heart.
So from this view, you're seeing mainly the right ventricle.
So just to quickly go over the basic structure of the heart and the function of the heart,
the heart can be thought of as a dual pump.
So you've got a pump to the lungs and a pump to the body.
Deoxygenated blood is received from the rest of the body into the right atrium.
It is then pumped into the right ventricle, which then contracts to send blood out through
the pulmonary trunk into the lungs where it receives oxygen.
Once oxygenated, the blood is returned to the heart via pulmonary veins into the left
atrium.
The left atrium contracts and sends blood into left ventricle, which then sends blood
out via the aorta to the rest of the body.
This blood is oxygenated because it's been received from the lungs.
So just when you're watching this tutorial, the blue-colored vessels are veins and the
red-colored vessels are arteries.
So the color of the vessel doesn't actually relates to whether or not the blood is oxygenated
in this model.
The blood that is sent out of the right side of the heart to the lungs is deoxygenated,
but on this model, you can see that the pulmonary arteries are actually red because they're
arteries.
This is the only artery that carries deoxygenated blood in the body.
And also, you can see the pulmonary veins which are returning from the lungs into the
left side of the heart, the left atrium are blue in this model because they're veins.
But again, these are the only veins in the body that carry oxygenated blood.
So just to point that out.
So between the atrium and the ventricles, you have valves, which prevent the backflow
of blood.
So between the right atrium and the right ventricle, you've got a valve known as the
tricuspid valve.
I remember the tricuspid valve as being on the right because tricuspid contains the letters
ri.
So tri, ri, right if you know what I mean.
If not, just try and remember that the tricuspid valve is on the right.
And on the left, between the left atrium and left ventricle, you've got the mitral valve.
You've also got valves between the vessels that lead away from the heart and the ventricles.
So between the pulmonary trunk and the right ventricle, you've got a valve called pulmonary
valve.
And between the aorta and the left ventricle, you've got the aortic valve.
So these are four valves that you need to remember -- the tricuspid one on the right
between the right atrium and the right ventricle, the mitral valve between the left atrium and
the left ventricle and you've got the pulmonary and aortic valves.
Don't worry too much about what these look like and the structures of them because I
will be doing a more detailed tutorial on the structure of the heart including blood
supply to the heart, all the different bits of the hearts and I'll be looking at the hearts
in more detail.
So in this tutorial, what I want you to remember is you've got the two atrium which pump blood
to the two ventricles and the ventricles pump blood through the major vessels.
And between the atrium and ventricles, you've got the mitral and tricuspid valves and between
the ventricles and these great vessels, you've got the pulmonary and aortic valves.
So the great vessels are those vessels which take blood directly to the heart, and take
blood directly from the heart.
So you've got four great vessels, you've got the vena cava, you've got the pulmonary trunk,
the aorta, and you've got the pulmonary veins.
So blood is brought to the heart by the vena cava, you've got the superior vena cava and
the inferior vena cava.
So you've got these veins which drain into the vena cava, called the brachiocephalic
veins, so you've got one on each side.