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Current time:0:00Total duration:9:18

Video transcript

so there are a few words that get thrown around and when I was going through and learning them I was always confused and so I thought I'd go and talk about them right now the first word is arteriosclerosis arteriosclerosis and I'm going to underline the 100 here and very similar to this word there's the word arteriolosclerosis arteriolosclerosis with an extra L & O and everything else is the same the first thing I always wondered was are these the same word that someone just misspelled but but actually that's not the case this is two separate words for two separate things and a third word is atherosclerosis as you actually used to wonder the same thing about this word just like is this just another way to spell it maybe the the British spelling or something like that but actually it's another word that's different in meaning as well so these three words often get confused for one of them and sometimes you'll even see that they are referred to as the same thing but there are some subtle differences that I want to talk about so let's start with the first two words artery oh and arteriolosclerosis and these basically get to the question answering the question of what what is happening and the process of arteriosclerosis and arteriolosclerosis is that you basically have stiffening of blood vessels so if you have let's say a normal vessel I'll draw in red like a like a little rubber hose this is a very soft flexible vessel and over time if it becomes stiff like a lead pipe then you have something like this very firm vessel so same size but basically the the walls are becoming very very stiff and our Triola sclerosis is kind of the same process and so so far I have not convinced you that there's any difference right same basic process so you're probably left wondering well then what is the difference going to firm well the difference is that arteriosclerosis is happening in the large arteries and middle sized arteries so large and middle sized arteries and remember we divided up the arteries into large a middle and on the other side we said what about the small arteries and arterioles and that's over here and arterioles so basically if this process is happening in the larger middle arteries we would call it arterial sclerosis with a single O but if it's happening in the small arteries and arterioles we would call the same process arteriolosclerosis so that's the key difference right where is it happening now in terms of answering the question of what this is the process but you know you have to ask ask yourself well why does that matter why does it matter if something going from soft to firm now I'm going to draw a little spectrum for you and on this side we have the word not and here you have very and these are referring to compliance so try to remember back to what we said about compliance and that's whether or not a vessel can stretch almost like stretchability and if you think about what would be very stretchable or very compliant we've got veins so that would be over here a vein very compliant right and arteries are over here they're not so compliant they're not completely stiff but compared to veins they're not much of the not very compliant so they have much lower compliance in veins and a lead-pipe would be right here basically right next to naught this would be a lead-pipe right and so when we talk about arterial sclerosis or arteriolosclerosis as something that's soft going to something that's firm we're really talking about the artery moving from where it is on the compliance spectrum over here towards not too compliant at all so really we're talking about losing compliance let me write that losing compliance that you're really important and that's really what we're talking about losing compliance all right now how do we get to a point where we're losing compliance how does that happen exactly well that's another question that's the question of how how does this happen and there we can talk about atherosclerosis so atherosclerosis is a process and that you know I can even draw it out for you very quickly and this is let's say a blood vessel an artery and I'll draw two layers for its wall although we know that there's actually three layers just to make it simple in destroying two layers just to show you there's a thickness and let's say that you have some fat deposit here and maybe one over here and over time we know that this is going to cause some blockage of the vessel but also in addition to losing space in the lumen this is the lumen in addition to losing space in the lumen you also have some calcification and some fibrous tissue starts kind of laying down here so this wall instead of being nice and soft and red I'm going to draw it as very firm and white very firm so this part of the wall and maybe even this part of the wall become very non-compliant they lose compliance here so these parts of the walls are very firm they're not going to stretch out very easily so that's atherosclerosis and the reason I listed it under under this section here if I can divide it in half is that most often not always but most often atherosclerosis is happening in the larger or middle sized arteries doesn't happen as often in the small arteries and arterials so it's happening more often than the larger middle arteries and so it's going to cause arterial sclerosis so atherosclerosis is the how and Archer is closest is the what for the large and middle-sized are now let's shift over to the small arteries and arterials so if I just told you that atherosclerosis doesn't happen too often in the small arteries well then how in the world do I does arterial sclerosis happen again Archer Eola with an O ello how does that happen okay let me write out for you a couple words these are words that you might come across hyaline and hyperplastic so these are just names for process so these are again these are answering the question hyperplastic there you go these are answering the question of how does arteriolosclerosis happen while it happens through Highland or hyperplastic arteriolosclerosis so that the word appears again here and this let me just draw up for you as I did before we have a vessel instead of having a plaque which which is what I drew before in my vessel this time I'm going to talk about blood pressure being really high so here we're talking about things like let me write over here high blood pressure or the diabetes so in situations like this you can have lots and lots of pressure pushing out of the vessel this is my little arrows talking about blood pressure and as the pressure is pushing out what happens is that some of the proteins from inside of the vessel let's say you have some protein in here get pushed out get pushed out into the vessel walls and that vessel wall gets loaded with protein no extra protein that doesn't usually belong there and it's got little protein everywhere because it's being pushed out by all that high pressure and over time having all this protein having all this protein here I'm drawing in pink is going to cause these vessels to start losing compliance so all the way around actually so they start losing compliance and again this is not how it always happens that this is just an example of how it could happen how it could happen you could lose compliance this way so this would be an example of how something that was soft is becoming very firm over time because of blood pressure related issues I will pick up there next time