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Current time:0:00Total duration:6:46

Video transcript

in the next couple of videos we're going to talk about two disorders that are often discussed together one is called my au car Dittus myocarditis and the other one is called Perry Perry car and Dittus and they refer to two different diseases that are inflammatory reactions of certain parts of the heart I think you may have guessed that just because both of them use this part card meaning cardiac and perhaps you also recognize that anything that ends in itis itis like that means that that's an inflammation or an inflammatory process of whatever it's coming after like cellulitis is inflammation of the skin optic neuritis is inflammation of the optic nerve so myocarditis is inflammation of the myocardium which is the muscle of the heart and pericarditis is inflammation of the pericardium which is the outer layer of the heart so I started throwing some fancy terms at you so let me define them so when we talk about the myocardium the pericardium where do they sit in our structural cardiac Anatomy so let's start from the very core and I'll draw a simplified heart of course you know the heart isn't really shaped like this but there are three layers to the heart I've drawn one right here and then there's another layer on the outside like this so let me just draw this layer out here and I'll color this layer there and then we can start to label things this inner layer right here and that also involves everything that's on the inside is the part of the heart that makes contact with blood as it's pumped through to the rest of the body this is called the endocardium the endocardium and we're not going to talk about endocarditis in this video but that's definitely a significant disorder to think about so that's the endocardium the next layer this meaty red layer that's on the outside is the muscle of the heart this is the myocardium so that's the myocardium so let me label that there and this is the part that's affected in myocarditis as we're going to discuss and then this outermost layer that's all the way around here it's sometimes called the EPI car diem so the EPI car diem but no one really calls it that the term most people refer to it as is the pericardium so it's the pericardium and in fact that does refer back to what we were initially setting out to discuss pericarditis is an inflammation of this layer but the pericardium isn't just one layer this layer that I've drawn here that goes like this and wraps around here we'll come back and reflect up that way and so let me draw it going all the way around comes down here flips back this way and then it comes and meets back up there and notice that this lining was coming in right here it flips here and then starts going that way so in a sense it's a continuous lining but it forms these two layers and I'll color this portion inside here this is going to be its own little cavity or this space here and we refer to this as the pericardial space this is the pericardial space alright and so I've set up these two layers right here of the epicardium or the pericardium and in fact the layer that's here that touches the myocardium and the inside of this outer layer here has a special name it's called the serous the serous pericardium and some anatomist will make distinctions this is the visceral layer of the serous pericardium and this is the parietal layer of the serous pericardium I'm not going to write those down because I think that's too much detail for what we want to talk about just know that there are two layers to the pericardium here and there's pericardial space and then finally on the outside this outer layer of the parietal layer of the serous pericardium has a lot of fib hrus tissue or fibrous tissue on it and so I'm just going to go around and just draw that and all that means is this outer layer is kind of rough and so remember the inside part of this lining is called the serous pericardium this outer layer that's a little more rough is called the fib hrus it's the fib hrus pericardium okay and the fibbers pericardium is what you would see if you were to dissect out the heart in a cadaver lab or when you're doing surgery so now that we know all of our different layers for our structural heart anatomy i can tell you that the myocardium is we discussed is the heart muscle and so any disease of the heart muscle will then undermine the ability of the heart to pump blood to the rest of the body and so myocarditis is an inflammation of the heart muscle which can then lead the heart to dilate or this wall can become thicker or the chambers can become enlarged making it difficult to actually pump blood out on the other hand the pericardium the serous pericardium which is the main thing we talk about here is the outer lining it's the outer lining of the heart and if there's an infection or some other inflammatory process of the pericardium that would make it even more stiff and so what that means is that when the heart tries to fill with blood that it receives that's deoxygenated or doesn't have any oxygen and it wants to send it to the lungs to get oxygenated or send it to the rest of the body it's not able to pump a lot of blood out because it can't collect it in the first place so if the pericardium becomes inflamed it doesn't allow blood to return to the heart and functionally that's the same problem here if you don't get enough blood back to the heart you can't pump it outside to the rest of the body alright so I think we have an idea of why it's so troublesome to have myocarditis or pericarditis and we've talked about the card part of where they exist in our enemy but let's talk more about the itis let's talk about inflammation and what does that mean