Cardiovascular | Anatomy of the Heart | Heart Model
Articles Blog

Cardiovascular | Anatomy of the Heart | Heart Model

September 10, 2019


alright Ninja Nerds we’re going to take a look here at the heart so if you look here at the heart this is the anterior surface of the heart this back here is the posterior surface of a heart inferior surface down here this is the apex of the heart and then up here is the superior surface or you know we actually say like that the base is going to be pointing towards the right shoulder alright so let’s take a look at the heart we’re going to kind of go over all the structures and anterior surface here so if you look here you can see this part right here this little fatty pouching here this is actually an auricle and it’s on again this is over here this is the left side and over here this is the right side so this is the left auricle and the left auricle is kind of like a fatty pouch and has some muscle tissue that also allows for it to kind of squeeze some of the blood into the atria in that area right behind this is going to be the left atrium I will show you when we take this this piece off over here we can see the right auricle all right if you look here this is going to be the pulmonary trunk that’s the pulmonary trunk its what takes deoxygenated blood from the right ventricle to the lungs to get oxygenated all right so that’s why it’s actually going to appear blue because it’s going to be taking again deoxygenated blood from the right ventricle to the lungs to get oxygenated so it goes pulmonary trunk and then it has this branch over here that we can see this is actually going to be the specifically the left pulmonary artery we’ll take a look at the bright pulmonary artery here in a second if you look here we have a big big vessel coming out of the heart this is going to be the aorta so this is the whole aorta right here this is the ascending aorta this portion here this is the aortic arch okay right here and then you have three vessels that come off the aortic arch in orders already this first one here is actually going to be called the brachiocephalic artery okay it splits into the specifically the right subclavian and the right common carotid the second one here is going to be called the left common carotid artery okay and there’s one back here all the way in the back here is going to be the left subclavian artery and then again the aortic arch will going on into the descending or we actually say first thoracic and abdominal but we’ll see that in other models all right now let’s go ahead and turn this a little bit and I turned it here to the right side this is this is the right side of heart so this is the right atrium right here if you look here we got a nice big vessel right here that dumps into the right atrium the big systemic vein this one right here is called the superior vena cava that’s a superior vena cava this vein right here and this vein right here they actually merged together one comes from the right side one comes from the left side so this is the right brachiocephalic this one right here this one over here is the left brachiocephalic vein okay so we got left brachiocephalic vein right brachiocephalic vein come together and make the superior vena cava which dumps into the right atrium there you can see this little veins that kind of like nothing off the back here it’s actually going to be feeding into the superior vena cava this is called the azygos vein well we’ll take a better look at it when I keep turning it around so we can look at the posterior portion of the heart some of those vessels let me keep turning it around little bit more alright guys so if you see here we can still see a piece of that aorta again that’s going to be the descending order it’s going to go down because the thoracic aorta down here then you can actually see nice nice view here of the pulmonary artery this one is the right pulmonary artery over here and this one over here is the left pulmonary artery so again those are deoxygenated vessels remember that they’re taking blood to the lungs to pick up oxygen that’s why they appear to be blue so most people be like all these are the pulmonary veins no they are the pulmonary arteries arteries by definition take blood away from the heart vein take blood back to the heart and then the veins that come back from the lungs are going to be oxygenated that’s why these ones are the pulmonary veins and they’re red so don’t get that confused again these ones over here are the pulmonary veins this would be the left pulmonary veins left pulmonary artery this one right there right a pulmonary artery over here is the right pulmonary artery and down here going to be the right pulmonary veins all right again you can actually see that vein that I was showing you before this one right there is be azygos vein that one right there and it actually comes up all the way from your actual common iliacs, it can bring blood all the way up and bypass the inferior vena cava we’ll talk about that with its relationship pregnancy and one of the other models again azygos vein there and then we’re taking a look at the post here portion of the heart now we’re going to do is we’re going to flip it back over and we’re going to take a look at some of the vessels with the coronary circuit and now here again back on the anterior aspect of the heart again we’re going to take a look at at the coronary circuit now the coronary circuit i’m going to show you that after when i take this piece off you’re going to be able to see two arteries coming off of the aorta and they’re the first ones to come off of the ascending aorta actually it’s the right coronary artery and the left coronary artery we have a video in the physiology where you can actually see the circuit in more detail also but this is going to are going to go over the anatomy here so if we look you can see this artery right here is going to be coming all the way down here and this one is actually going to be the anterior interventricular artery right there anterior interventricular artery but they also can call it the left anterior descending artery okay this is one of the most common areas about forty percent of the myocardial infarctions actually occur within this artery well due to the blockage of this artery okay because it supplies a good chunk of muscle supplies the anterior walls of the ventricles right on the left and the right and it supplies the actual anterior wall of the interventricular septum another branch so again this is actually going to be this artery right here comes off of a specific coronary artery and that is the left coronary artery so remember left coronary artery gives way to two arteries this one right here anterior interventricular again or you can also call it left anterior descending and the other one is going to come off of the side over here and that’s going to be this one right here number 11 that’s going to be called the circumflex artery so the circumflex artery actually kind of wraps right around this auricle you can supply a little bit of the atrial muscular wall and it can supply some of the lateral walls of this left ventricle over here okay not too common of an area for the myocardial infarctions or blocks clots to form than that one alright now we’re going to do is we’re going to turn it back over here because now I want to cover the veins in this area so if we come back over here what happens is the anterior interventricular artery or the last left anterior descending takes blood to the myocardium drops off the oxygen after drops off the oxygen it picks up the co2 and it’s going to have to come back through a vein well the vein that it comes back through is this one running right next to it that blue vein there running right up this guy is called the great cardiac vein the great cardiac vein which is going to be number 14 here okay so number 10 is the left anterior descending or again anterior interventricular and 14 is going to be the great cardiac vein all right and these kind of both run down what’s called the anterior interventricular sulcus which is like a fat filled groove primarily the anterior ventricular artery runs out Down this little fat filled groove right there which is called the anterior interventricular sulcus alright so again great cardiac vein now if I turn it over here go back to the circumflex artery well what vein over here drains it there’s a vein right next to him right there okay that’s called the posterior vein of the left ventricle so that drains the myocardium and brings the blood back right that’s that one now what we’re going to do is we’re going to take a look at the branches off of the right coronary artery so if we look over here this right here is the right coronary artery right here to running all the way down 155 it’s running all the way down what’s called this coronary sulcus so it’s running down this fat filled groove here called the coronary sulcus then it has a branch that comes off of it right so this is one branch right here and this is actually going to be number eight I turn a little bit better you might be able to see it this is number eight right here that’s the marginal artery the marginal artery supplies the lateral walls of the right ventricle right and then if you look here it goes in delivers oxygen to the myocardium after delivers the oxygen to the myocardium picks up the co2 and it’s going to have to come back through the vein will add vein does it come back through it comes back through this vein number 12 and that’s going to be called the small cardiac vein okay these ones they don’t talk too much about it but this one’s called this just called the anterior cardiac veins that’s the anterior cardiac vein and then this one right here which is kind of a little bit more important it’s the small cardiac vein all right now what happens is the right coronary artery continues to track its way down through this coronary sulcus and as it tracks its way through the coronary sulcus it comes around the heart and what we’re going to do is we’re going to take this heart off so we can see a better view of another artery branch all right guys let’s track that right coronary artery so we’re tracking that right coronary artery back here to the posterior side of the heart and as we come over here it gives off this branch down here look at this guy all the way down here all this right here even a little bit of this part over here this is all called the posterior interventricular artery so again all this puppy right here and even a little bit of e branches off here so that’s the posterior interventricular artery and it runs through a fat filled groove which is called the posterior interventricular sulcus so now this is delivering oxygen rich blood and it takes it to the myocardium right so when it takes it to the myocardium it drops off the oxygen picks up the co2 in the waste product and it’s going to come off of that capillary bed through a vein well guess what vein is going to be running through the one right adjacent to it this one right here 13 all this puppy right here this is all called the middle cardiac vein all this right here is the middle cardiac vein all right so little cardiac vein here’s another piece of it all that is the middle cardiac vein now all the middle cardiac vein it will also dump when it combines with the small cardiac vein the great cardiac vein the posterior vein of the left ventricle all of those guys will combine and dump that blood into this big big vein up here called the coronary sinus and then the coronary sinus dumps it into this cavity in here or this chamber called the right atrium alright and this would be inferior vena cavas this big gaping hole right there alright next thing I want to show you guys something really cool if I turn the heart a little bit over here you can kind of see the posterior interventricular artery kind of confuses or Anastamoses with the marginal artery over here that we already saw so here’s our marginal artery and it forms an anastomosis a collateral alternative channel for the blood to flow through with the posterior interventricular artery so that’s a cool arterial anastomosis alright so if we look here we got the circumflex artery right this was the one of the branches off of the left coronary artery well guess what it can anasta Mose with the posterior interventricular artery so there’s an anastomosis between the circumflex artery number 11 over here and the posterior interventricular so that’s a pretty anastomosis now it’s go to the anterior side to see some more anastomosis but look over here this artery coming off another branch of the left coronary artery is the anterior interventricular artery and it actually comes off and look there is another anastomosis with the circumflex artery so this is an anastomosis between the anterior and interventricular artery and the circumflex artery alright but then if we turn it over just a little bit more again we have the marginal artery over here and the marginal arteries look it anastemosis here with the anterior interventricular arteries so we have all different types of astemoses here and it’s just really really important to know that arterial Anastomoses provide alternative or collateral routes for the blood to flow to in case there might be some type of thrombus or embolus or clot of some form it just ensures that enough oxygen will get to the tissue alright guys so now what I’m going to do is I’m going to take this and this part off here so we can kind of look inside of the heart alright let’s take a deeper look inside of the heart so if you look here we have the two top chambers this chamber right here is going to be called the right atrium this chamber right here is going to be called the left atrium alright so together we call them atria right then if you look here we have a valve a nice little valve right here that separates the right atrium from the right ventricle this valve right here is called the tricuspid valve okay and if you see these little cords coming down from that valve the leaflets this is going to be called the chordae tendineae the little collagen cords all right and they’re going to be anchored down by these muscles right here they’re anchored down by these muscles which are called the papillary muscle you can see that one right there 154 and you can see the other one over here really really well which is angering down that chordae tendineae nice all right let’s turn it over a little bit more so we can see a couple other structures inside the right atrium alright so now that I got a better view here let’s take a look you can actually kind of see a little bit of scar tissue if you remember from the fetal circulation video there was a hole here and that hole was called the foramen ovale right and that’s what allows for blood to get shunted from the right atrium all into the left atrium to bypass the pulmonary circuit well after the fetus is born this turns into a scar tissue right here and it’s now called the fossa ovalis again it’s called the fossa ovalis it’s just a scar tissue right there okay and then if you look here that number 26 that little black hole right there that’s the opening of the coronary sinus so if you remember the coronary sinus the one who collected the blood from the middle cardiac vein, great cardiac vein, small cardiac vein Posterior vein of the left ventricle and anterior cardiac veins it that that’s the part that it’s emptying into the right atrium alright and again we already said tricuspid valve here we already said the chordae tendineae there and we already said the papillary muscles and then again this whole chamber down here is the right ventricle all right so now let’s go ahead and take a look here if you remember the ventricles the ventricles re you’re pumping chambers so they’re the ones that are designed to contract and pump blood out of heart so what they do is they pump blood up through this pulmonary semilunar valve okay this little crescent-shaped looks likes it looks like half a moon right so that’s again that your pulmonary semilunar valve right there and remember we’re going to talk about this it goes up into the pulmonary trunk now you’re into the pulmonary arteries right and if you look right here i’m going to turn a little bit more go for you guys you can see this little structure right there that little white structure there that is called the ligamentum arteriosum oh if you remember when we did fetal circulation it’s called the ductus arteriosus and it’s a shunt that shunts the blood from the pulmonary trunk into the aorta to bypass the blood going to the lungs so whenever the baby is born it turns into a ligament to close that hole off right and again becomes the ligamentum arteriosum alright so now let’s go ahead and turn it over more so we can see the left atrium and the left ventricle over here so these look you got that big hole right there that’s the opening of the right pulmonary veins so the blood that’s coming from the right lung is actually empty into the left atrium over there and that hole and then if you look over here we got these two little tiny holes over here is coming from these veinss right here that’s actually going to be the opening of the left pulmonary veins and they’re going to be taking blood from the left lung and taking and dumping into the left atrium again remember that this left side is only getting oxygenated blood the right side is adding deoxygenated blood so oxygenated blood here gets pumped down right through this valve right here this is called the mitral valve or the bicuspid valve right then it has these little collagen cords dangling down from the leaflets which are going to be again are called the chordae tendineae and if you look right there 154 you can see the papillary muscles right there which anchor the chordae tendineae down alright guys so what I wanted to do is I want to take another view right here to look inside of the ventricles you can see this little valve right here this is called the aortic semilunar valve so again the aoritc semilunar valve is what prevents the back flow from the aorta into the left ventricle I just want to give you guys another look at that that’s your aortic semilunar valve right there and we look you see all this thick part here this structure this is called the interventricular septum and certain types of defects and like the tetralogy of fallot there can actually be a little a little septal defect there where actually blood can jet between the two all right now next thing is if you look here which we can kind of highlight all of this muscular layer which again is made up of cardiac muscle right so all of this is cardiac muscle right here cardiac muscle cardiac muscle we get that specific layer a name and we call this part the myocardium all right the lining the internal chambers of the heart which can be any part anything allowing the internal chambers of the ventricles any internal chamber of the atria and he’s in lining the valves contains a simple squamous epithelial tissue which is actually going to be consisting of a little bit of areolar connective tissue and we call that endocardium alright endocardium it again aligns the internal chambers of the heart and the valves alright so again guys you can see the anterior part of this right so now what I’m going to do is I’m going to take this piece off here so we can kind of look at some of the more internal structures inside here so if you look there’s actually going to be these little muscle linings right here so a little muscle tissue again and to your walls of the atria and they’re kind of hard to see it’s actually kind of looks like someone combed them they’re called the pectinate muscle so pectinate muscles are up here in the anterior wall of the atria right and then down here you can see all these gnarled irregular fibers of muscle this is called the trabeculae carne and the trabeculae carne is only in the anterior walls of the ventricles against the trabeculae carnae and the anterior walls of the ventricles and pectinate muscles here in the anterior walls of the atria alright so now that last thing to kind of wrap everything up for the hard guys if you look the outer layer of the heart is actually consisting of a specific type of tissue that actually can call mesothelium and what it’s made up of it actually the outer layer is actually called the epicardium but it’s made up of simple squamous epithelial tissue with a little bit of aerial or connective tissue and it’s again it’s going to be covering outer part of this heart right here alright so if you remember in our videos on structures and layers of the heart we go into more detail on that but again just showing the anatomy here this outer layer of the heart is going to be consisting of epicardium which is a made up of simple squamous epithelial tissue a little bit of areolar connective tissue and again you can call that mesothelium alright that pretty much takes care of everything for the heart see ya ninja nerds!

Only registered users can comment.

  1. Thank you for all the hard work and passion that you’re dedicating for this channel ❤️❤️❤️❤️ keep going

  2. You explained the whole heart in one video!!! Thank you!!! This helps put everything together for me and now it all makes sense.

  3. In a 2nd degree heart block how come you can't see atrial repolarization following the P-wave even though there is no QRS segment present. Does the EKG not read atrial repolarization?

  4. I hv got2write my PG entrance exam soon sir. If u can do this favour by putting acid base balance video asap, thn it'll b easy for me to crack the exam sr.

  5. Great video!! Just a quick note, in the very end you say that the outer lining of the heart is called epicardium. But in reality it's called "pericardium" and epicardium is one of the layers of pericardium, more specifically the visceral layer of the serous pericardium. Other than that it was very useful, thank you!!

  6. Just curious besides your AWESOME videos, what books/textbooks do you recommend to read as I also follow your videos for mastery? (for a non-school student btw) Thank you!

Leave a Reply

Your email address will not be published. Required fields are marked *