all right let's continue then with blood vessels today the science of blood vessels is called quite an Jia and geology and G oh gee so angio will be vessels so we're going to look at the blood vessels in the systemic circulation which will start this will be systemic circulation going if we have the heart and our four chambers our left ventricle all right atrium and we'll follow arteries the ascending aorta is coming out here but we're just going to call it an artery for the moment coming from our left ventricle this will be an artery and then gradually it will be rewired it will gradually decrease in size to form an art form arterioles arterioles these are smaller and then continue to decrease in size down to capillaries these are our capillaries and then we come back up on the venous side in small veins called venules venules and these will enlarge to form veins and bring the blood back into our right atrium giving us a circulatory system here and this will be our veins now all of these vessels have three layers except what capillaries capillaries will just have to they'll have endothelium plus a basement membrane some authors like to use the term lamina a basement a basal lamina same thing so now what we'd like to do is begin with arteries and there are two major classes of arteries elastic arteries and muscular arteries and we'll begin with the elastic arteries because there are the ones coming out from the heart so that they're going to be expanding they need elastic tissue can I take this off we call the coats or the layers of arteries tunics tunics so we'll have the layers you'll define here just those are tunics the opening is called what a lumen yes illumined to give it its specific name so what we'd like to start with will be the tunics on the elastic arteries we said we had three of these layers so these are elastic arteries we're going to start with the first one which is for Tunica intima so this is inside next to the lumen well we'll have endothelial cells because throughout your whole vascular system you're lined with endothelial cells endothelial cells plus connective tissue fibers and these will be primarily elastic then we'll have the tunica media the middle layer tunica media which will have predominantly elastic fibers plus a little smooth muscle a little bit of smooth muscle now our third layer again it's a Tunica the tunica adventitia adventitia and again for these elastic arteries lots of the CT will be elastic fibers but also collagenous fibers collagenous fibers for strength the adventitia has something else that the other layers do not have it has the blood vessels of the blood vessels so we'll find the blood vessels of blood vessels in the adventitia layer the correct name for this arbaiza vase Orem they'sa they Sorum it's funny how you remember things I remember when I first learned that when I was your age these of us or I'm just saying it now it's all up there so this gives us then the wall of our elastic artery now where do we find elastic arteries we'll show them coming from the heart so this will be what are we calling them do we call them names I say examples of elastic arteries so one is going to be our a sending a Orca we know that it's coming from the left ventricle so we're going to put in one coming up equals the ascending aorta does anybody know what the first branch off of the a sending aorta will be what's the most important thing coronary artery I always tell it's a good philosophical point take care of yourself so you can take care of everybody else the heart takes care of itself first the first branches off of the ascending aorta will be the right and left coronaries we're just going to put them in here so this will be number two right and left coronaries and then number three as we come up go off in this direction this will be the brachiocephalic brachial what's brachio mean arm cephalic head so send branches down the arm and also to the head and also the theorem that used to be used but when we have our vascular surgeon come he come in he uses it still so I'm going to give it to you so you know that it's the synonymous artery of the brachiocephalic is also the innominate [Music] marjory it's the same and now our next one will be the arch of the aorta going off in the opposite direction here big arch it's not an inch in diameter unless you get an aneurysm here gets to be five inches that's something take good care of your blood vessels number 4 will be the arch of a Horta and then we'll come back and put in the left subclavian this will be five left sub clave Ian what does that mean under the clavicle just palpate your clavicle you know you've got a subclavian under there a big vessel and off of the subclavian in this direction we're going to have the right common carotid number six whoops I'd put left I'm sorry that should have been right to plate I apologize this is definitely right then six is the right common carotid and then we can follow over to the opposite side where we'll have seven which will be the left common carotid left common carotid and eight is what then hmm same is on the opposite side would we have over on the opposite side subclavian sure left subclavian so these then are your elastic artery so when you have systole down here and the ventricles that pump is going to expand these arteries and then when they recoil they keep the blood propelled to keep it going around the body so that's why you need elasticity and we'll see what happens when you lose it with aging which is a possibility all right let's take then a few of these as examples and expand upon them let's take the coronary arteries can I take this off no objection so coronary arteries why do we take these arteries because a third of the population that dies in the US will die of heart attacks lock each of your coronary arteries our water commonly called heart attacks so I third of the population that died in u.s. yeah I'll do the heart attacks so it does sound is this important that you understand the mechanism what happens what are we going to do first we're going to be obstructing the Tunica intima the first stage in getting plaques in arteries begin in Tunica intima what do we call when we start getting plaques in our arteries what's the term atherosclerosis plaques in arteries and these plaques can be rich in cholesterol that's why you watch your diet in fact it's been reported that some 25 billion dollars are spent in a year on anti cholesterol drugs on anti-cholesterol drugs so it's very important when you get your physicals when you're young to find out your cholesterol level in the blood so you know what you're treating so you can watch it because if it gets above 200 then it becomes more dangerous cholesterol it's just the number used 200-plus becomes dangerous No so it's very easy to get your blood tested and to find this out and to know how to change your diet if you're eating ice cream every other day you know to switch to yogurt you just learned there are substitutes for the heavy fats you can do that but look at how many people do not tremendous so now let's see where we want to take this say that you've got your coronary obstructed how are you going to get rid of the obstruction you have obstructed coronary you'll have an operation called angioplasty most have heard of it today and geo blasty that's the operation to remove black basically there are two steps you can use some of the basic anatomy that we've learned we're going to inject a radio opaque material into the femoral artery where would you go to the femoral artery if you are going to inject something what do you call it femoral triangle sure so you know where it is now so we're going to inject a radio opaque substance into femoral triangle and this will outline your blood vessels so they can be seen with an x-ray x-ray so with this technique you can localize where is the obstruction in the coronary artery localized obstruction so now you know where it is so the second step will be to insert a catheter in the femoral artery insert catheter a catheter is a tube and at the end of the tube there will be a balloon because what one's going to do is inflate the balloon to push the plaque to the wall so insert a catheter with a balloon and the balloon is in what's called a stent with a balloon in a stent what is a stent in this case the stent is a wire mesh tube equals a wire mesh tube so here we are with our catheter and it's got a balloon attached to it here and surrounding the balloon will be this stent wire mesh and we're coming into an artery with a plaque so this is a plaque this is my artery when they get there then they will inflate the balloon and it will extend this stent up against the plaque then we're going to insert catheter way down here in the groin threaded all the way up through your abdominal aorta around through your arch and around to the ascending aorta and into your coronary artery that's where we are here adhere we'll inflate the balloon enlarge stent to press plaque against wall and then you can remove the balloon and the catheter and leave that stent in place there was a professor in endocrinology of catch in a second and he had been obliterated or blocked coronary but he got to watch the surgery and he could see that no blood was going into his coronary that was blocked and soon as they put in the stent and he saw the blood he said that was one of the greatest thrills in his life so now this heart was once again trying to be before he came back and I was in lab and he came in and disturbed to tell me the excitement so let's hope that you keep healthy arteries so you don't have to do that yes to a degree yes but not wholly it's not going to be that big right not until you get up here and get it and then get this out all right that's very clever what are they doing today this is very common but they're using a laser to vaporize the plaque they have a catheter with a laser and they thread the catheter up to the plaque and then activate the laser and it disintegrates the plaque it vaporizes it's the term they use vaporizes plaque so what next with technology that's why you take these basic courses to see how you're going to improve things yes yes the stance stays in there right all right so that tells us if you get a plaque in your coronary artery what happens if you get plaques in your common carotid I think we'll come back to that let's see which one we want to take now no I can take common carotid so it's quite common to get plaques in your common carotid so we have our common carotid it's coming up here we had our heart we have our a sending coming over to our loop and our common carotid on the left brachiocephalic out here and our common carotid on the right and they'll stay as common carotid till they get up to the superior boundary of what what is this in here this cartilage oh sorry it's not cartilage it's the larynx will study the larynx it's part of your respiratory system one has to keep cartilage to keep it open so it doesn't collapse but at the superior border of the larynx the common carotid is bifurcate common carotid bifurcate into a internal carotid and an external carotid internal carotids add my external carotid at that point of bifurcation that is a common site for plaques to form because you're coming up and you hit the top here before it goes off so plaques commonly form at bifurcations in the carotids this area is important because we have two sensors here we have a carotid body again this is at the bifurcation of common carotid we have the carotid body that regulates blood pressure regulates this is in the wall of the artery regulates blood pressure via the ninth cranial nerve we also have a very important structure the carotid sinus what does a carotid sinus do it regulates respiration by sampling oxygen in the blood regulates respiration by sampling oxygen so you can see how important feeling your neck feel your current your larynx its your Adam's apple common term so you know just to the right there will be this bifurcation of your common carotid and that you have these very important sensory mechanisms right there in your neck as far as your blood function goes so it's let's look then at what happens if you get your plaques in the common carotid as we go down get plaques forming here how are you going to determine where whether their plaques there fortunately you don't have to come up through the femoral artery clear into the neck what can they use to determine plaques in the neck ultrasound with ultrasound you can determine plaques in the ultrasound to determine plaques in common carotid and they are quite common these plaques in this area so older people get ultrasounds to see if they have plaques what do they do if there are plaques they do a procedure called end arter ectomy and are correct to me that's procedure to remove plaques in common carotid then I was just meeting yesterday that they're saying that by many people over 80 it's still safe to do an in dr. ectomy and it certainly increases the blood supply to the brain there's the typical story they tell about the executive who was losing his memory and his secretary kept trying to make up for it but finally she talked him into getting it into our ectomy and they went in and cleared out the plaques and he could get the blood again going to his brain and his memory came back very well so there are lots of reasons for decreasing memory when you get older got to consider the health of your vascular system so these then give you some examples of our elastic arteries and what they do and how we can keep them healthy let's look at our muscular arteries then because obviously the majority of your arteries are muscular arteries I've only given you eight elastic arteries so we have muscular arteries you ever thought about your arteries before not too often they're down on the list are they when they're so important these are also called distributing so how are you going to tell the difference between a muscular artery and a distributing artery by its coat you have a Tunica intima Tunica intima shirts better have it's endothelial cells answer them connective tissue but it also has an internal elastic membrane internal when I show you pictures you'll see how distinct it is internal elastic membrane I mean if 30 of us have got to die of vascular problems I think we should really be well aware of what our blood vessels are we've got a tunica media who's the professor in anthropology few months ago died in front of his class got his heart attack that can't happen tunica media you're all go look at me funny now okay tunica media since these are muscular arteries we're gonna find the whole media filled with smooth muscle smooth muscle and then the tunica adventitia will be connective tissue collagenous fibers these are predominant but you can begin to figure out if you want to get a tough protective coating around an artery you're gonna put in collagenous fibers this will protect the artery and give it strength so it definitely will then have in addition we had an internal elastic membrane our adventitia is going to have an external elastic membrane so we'll see pictures so these are the three constituents that we have in the walls of our muscular arteries now a few examples in of muscular arteries let me take the internal carotid you saw where it divided it's going to feed 75 percent of your brain this whole brain is getting fed by the internal carotid supplies seventy-five percent of the blood to the brain so you see how important you can see why they're called for carotid switch what did carotid mean stupor right press on them look at how much blood you stopped going to your brain terribly important first branch of the internal carotid we'll be the ophthalmic artery where is it going to be going to the eyeball ophthalmic artery very important for you to see selmak artery goes to the eyeball now when you take advanced anatomy you get all the arteries coming off of internal carotid I'm giving you two the first and the terminal branches terminal branches anybody know the terminal branches go to supply your cerebral hemispheres the anterior cerebral and the middle cerebral anterior cerebral and middle cerebral so we can show how much of your cerebral hemispheres are supplied thank you by these two arteries I'd like to finish if I could so if we look at a lateral view of cerebral hemispheres I learned yesterday that we're establishing a new Institute called theoretical neurobiology and they'll be studying only the cerebral cortex and the thalamus leading to it fantastic big new thing so here's our lateral view our medial cerebral artery will be supplying an area like this all of this side put your hand side of your head you have your big hemispheres beneath it in red we've got the middle cerebral supply and we'll put anterior cerebral in blue even though it's artery just to distinguish it between so this is all anterior cerebral just one more thing here we'll pick up the vertebral next time there's a very important area here on the inferior frontal lobe this is left side what is it Broca's area right x equals Broca's area this is motor speech for me to be talking to you now if mine is firing getting more blood supply motor speech students will come in and say their grandmother had a stroke I said tell me one symptom she can't talk you know immediately that it was a middle cerebral and this is a question you'll get asked when you start on the floor with your residents what vessel supplies lateral cerebral cortex and I want my students to say what all this work and they say nothing middle cerebral don't forget it as more students come back years they say well thanks for telling us because that was a very question when they get to the brain they ask because it's a large supply we'll learn when we study the brain how much more is supplied here let's look at slides we have just a few minutes and we have some good slides so please let's move forward slide first this is an elastic artery this is the lumen the endothelial cells are here very thin but all the wavy lines are elastic fibers you can't see that there's one layer then the middle layer then the outer layer there's so many elastic fibers in contrast to a muscular artery next slide look at that you could distinguish here's my internal elastic membrane here are my endothelial cells this then is my muscular layer this is all smooth muscle and this then is our adventitia very clear differentiation between connective tissue smooth muscle internal elastic membrane endothelium and the lumen in this case is filled with blood you wonder how they they got that tissue why isn't it clear why is there blood after death who knows next one now this is a longitudinal section of a muscular artery because you're going to see them when you get to path you have to be able to see every different slice to tell what it is you might say well this is an abnormal no it's not abnormal your endothelial cells here's the internal elastic membrane here's your muscle cut in cross-section and here's your connective tissue next one this is an arteriole it's much smaller and these are circular smooth muscle cells around it you will have its little connective tissue its endothelium but greatly reduced in size because it's feeding into the capillaries next one and this shows them the arteries we've been mentioning as we see the ACE ending they put off some little coronaries here and then show your brachiocephalic here and then a common carotid we didn't get to the vertebral but we will next time because the vertebral will be supplying 25% of the blood to your brain but it's coming up the back of your neck and so you follow the common carotid up and the external carotid it's going to go external and supply your face and scalp while the internal goes into the brain next one now this shows at the brain here's your middle cerebral supply here's your middle cerebral artery this whole big circle here and if this were a left brain Broca's area would be about in here this shows a medial slice we've cut through the brain here's your corpus callosum here's your anterior cerebral artery when they first started split brain preparations to cut the corpus callosum they kept getting bleeding because this anterior cerebral hugs the corpus callosum and I learned from some of the lesser people down at Caltech when they cut they didn't they finally learned not to go so far forward and they left a little corpus callosum even though they called it a split brain preparation they didn't want to get this artery next one and this is what it looks like if we take all the brain away and that's the arterial supply of your brain don't you appreciate it now picture that inside your skull transpose it when we study the brain in detail as we do in the graduate class then you get all those arteries you see I'm giving you just a suggestion don't you appreciate your brains you