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Current time:0:00Total duration:10:34

Video transcript

in this video we're going to be talking about what is cardiomyopathy and to start I'm going to just write cardiomyopathy in three parts and the reason I do this is because if you breakdown cardiomyopathy into these three parts you get an understanding of what the disease is and so because cardio stands for heart Myo stands for muscle and path e stands for pathology or disease so you can get an idea that cardiomyopathy is a disease of the heart muscle all right now before we really dive into cardiomyopathy let me just kind of go over up do a brief review of what the heart muscle exactly does so I like to think of the heart as a series of two pumps that are separated by the lung so let's draw that in here and this first pump i'm going to call the right heart and the second pump i'm going to call the left heart so the purpose of the right heart is to bring blood from the body and send it to the lungs so let's see how that works well think about this pump just kind of drawing up here and it's going to bring in some blood so let's see that happen so now that the right heart has drawn blood into it from the body it's now going to pump that blood to the lungs then once in the lungs the blood is oxygenated and then the left heart is used to pump the blood from the lungs to the body and this is in a very similar manner as the right heart so let's see that here and what's cool about the heart is that these two pumps are actually pumping simultaneously they're both going up and down and bringing blood from the body to the lungs and from the lungs to the body and then this blood actually that's going to the body eventually circle it circulates back to the right heart you know it goes to all the different organs where oxygen and different nutrients and waste are exchanged before it goes back to the right heart and it just circulates like this and it's these two pumps that keep the blood moving through the body so this is just kind of a very simplified diagram of how the heart works let's put in a little bit more anatomical diagram of the heart to give you an idea of how these two bumps are kind of contained in one unit that is the heart so here we have a diagram of the heart and I want you to think of this heart as if you're looking at someone and this heart is inside of them so it's kind of mirror image so over here on the Left we have the right heart and then over here on the right we have the left heart and what happens in the heart is that these this muscle the the walls of the heart are a big muscle and when these muscles relax the the chambers of the heart actually get bigger so let's kind of see that and this dilation of the Chamber's just like in the pumps up here it draws blood into the Chamber's and this is where it comes into where I say it's kind of like two pumps because it's at the same time it's drawing blood in up in the right heart from the body and at the same time it's drawl so drawing the blood into the left heart from the lungs now that the blood is into this chamber into these two pumps the heart muscle this wall here it contracts and it makes that chamber a lot smaller and that's that can this contraction force of the muscles that actually expels the the blood in the heart chambers to either the lungs from the right heart or to the body from the left heart so now that we have an idea of how the heart works as two separate muscles within one unit pumping blood from the body to the lungs and from the lungs back to the body let's say I'm going to kind of erase my work here and show you how the heart muscle itself can become diseased and result in a cardiomyopathy all right so I'm going to just draw three more pumps here so there's kind of three ways that this the heart the muscle of the heart can fail and and the first one is that you can have a power failure or you can have a pump that's just too small and lastly you can have a blockage so in this first example the pump is supposed to kind of go all the way up and down but imagine if this pump doesn't have quite enough power and it's not able to pump this full distance they say it's only able to pump you know maybe from like here to here just this very short distance so every time this pump goes up and down it's still working in the fact that in it since it's drawing blood in from the body or from the lungs but it's just not drawing as much in with each pump and therefore when it pumps out it's also not pumping as much out so this pump is not as efficient and it's failing and so I'm going to just define failing here as kind of a decreased output of the pump so if your pumps only going a little bit up and down if you have a power failure you're gonna have a decrease output of the pump and another problem you could have with your pump is that the chamber of this pump is too small now this pump it's it has a smaller chamber in the side so even if this pump is able to pump that full distance up and down it's still not bringing as much volume as much blood into the chamber and pumping it out so in this case you have this power failure where it's not going up and down as much so it's not so the output of the pump is lower in this case it's going up and down all the way but the chamber is smaller so the volume that it blood it brings in and out is also decrease so maybe I'll write that in here we have a decreased flow coming out of the pump and over here we also have a decreased flow coming out of the pump alright so how about this lack last mechanism well let's just imagine there's a blockage here kind of in the outflow of this pump it and so now when this pump is going even though it's going you know the full distance up and down like in this example but the flow the blood that's trying to come out of the pump it's getting it's getting blocked and so you're not getting as much flow out of the pump so that once again here we're going to have a decreased flow and these are the three different mechanisms by which the heart muscle can fail to result in a cardiomyopathy so let's see how that works with a few hearts now let me just draw these hearts in here alright so in this first example I said we have a power failure well what does that look like in a Cardian cardiomyopathy terms or what happens in the heart well what happens when you have a power failure is actually the the chambers of the heart dilate a lot so let's draw that in here they get really big so when the chambers of the heart dilate like this it actually stretches the muscle really thin of the of the heart wall and that that muscle that being stretched so thin it's not as effective at pumping it doesn't have as much power so kind of like a peer work and kind of just go up and down just a little bit but not the full pump that's kind of what happens here is that these the heart muscle isn't able to fully pump and so even though it's getting bigger it still kind of got this power failure it's not pushing as much blood out of the two pumps and this power failure and dilation of the the heart chambers is known as dilated cardiomyopathy and so dilated cardiomyopathy is kind of aptly named because the heart chambers become dilated and it's that dilation that thins the muscles that causes it to have a decreased forward flow and and a failure of the heart all right so now let's talk about the small pump your example and how does this correlate to a cardiomyopathy well in this case the muscle walls of the heart chambers become really thick so I'm going to just draw that in here and when this happens when these walls become kind of thick and scarred down they're not able to expand and that expansion a relaxation of these muscles is what draws blood into the Chamber's from the body or from the lungs and so it's kind of like here where you have this smaller chamber now that it can't dilate out the chamber effectively becomes smaller so even though every time this muscle flexes and it pumps the blood out it's pumping almost all of the blood that's contained in these ventricles or the do these chambers but it's not able to bring enough in to actually have a normal flow out and when this this is known as restrictive cardiomyopathy so now let's go to this last example here we had a blockage of the outflow and how does this relate to a cardiomyopathy well in this example there's also kind of this thickening of the heart muscle however in this case this thickening of the muscle wall is actually asymmetric and in this center portion here known as the septum it becomes really hypertrophy - goes really big and it actually blocks the outflow of blood through the aorta which is sending blood from the left heart here to the body and so you get this blockage but you also do kind of have some of this small pump phenomenon and this is known as hypertrophic cardiomyopathy so to recap this real quick just remember that if you break down the name you can kind of remember that cardiomyopathy is a disease of the heart muscle and this disease of the heart muscle results in a decreased outflow of blood from the heart and it can kind of be caused by three different mechanisms you can either have a pump failure as you see in dilated cardiomyopathy you can have a pump that's just too small like as in restrictive cardiomyopathy or you can have this blockage of the outflow of the blood from the heart as you SC in hypertrophic cardiomyopathy