I'm engineers in this video we're going to talk about the coronary circulation the coronary circulation is very very important it is the circulation that's provides the actual oxygenated blood to the myocardium of the heart so the coronary circulation is again one of the most important circulations within the body the reason why is it's supplying oxygenated blood to the myocardium the muscle of the heart now the coronary circulation where does it actually begin well it starts particularly in the left ventricle so let's go ahead and start there so first off we're going to have the left ventricle the left ventricle is super super important because it's the systemic pump and in this case the coronary pump so this is going to be the first one the left ventricle the left ventricle is going to be pumping blood okay when it pumps the blood out of the left ventricle it's going to go up through a very important structure which is called the aortic semilunar valve so the next structure that is going to move through is it's going to move through what's called the aortic semilunar valve okay so the left ventricle pumps the blood up into the aortic semilunar valve when it pumps it through the aortic semilunar valve it goes into the ascending aorta the order is actually rising up right so then it's going to go into the next which is called the ascending aorta now the valves right behind those valves there's actually into these tiny little arteries okay tiny little areas called the right and left coronary artery they are super super important here's the next thing whenever the ventricles are contracting they're pushing the blood out into the aorta now this is during the systole whenever the heart goes into diastole it undergoes relaxation the valve flaps are going to snap shut right to prevent the blood from flowing back into the left ventricle but one snaps those valves shut it shunts that blood right into the coronary circulation so what does that mean then that means that the myocardium of the heart is getting its oxygen supply when the heart is in diastole when it's relaxing that is super important okay so ascending aorta is going to pump the blood into two different coronary vessels let's say that this is the right side that's the left side this one here is going to be called the right coronary artery okay this is the right coronary on the other one over here is going to be the left coronary artery now here's where it's really important the right coronary artery is going to move down this nice little sulcus okay there's a nice little groove a fat-filled groove called the coronary sulcus that right coronary artery is going to run right down that little sulcus and when it comes down the soak it's going to give off a little branch one of the branches is going to give off on the rights of the heart is going to be called the marginal artery so one of the branches is going to be called the marginal artery that's one really important one it's going to supply some of the actual right ventricle and a little bit of lateral side of the right side of the ventricle is a little bit of right and inferior part of that ventricle another one is called the posterior interventricular is going to continue to move around and it's going to supply the posterior aspect of the heart and this is a really really important one again so this is called the posterior interventricular artery okay so this is the posterior interventricular artery then the left corner is going to give off two branches so why were the left coronary artery comes in and gives off a branch that moves completely down it descends on the anterior aspect of the heart if you have two names for this one you can call the anterior interventricular artery or you can call it the left anterior descending artery okay it doesn't matter but again you might hear one of those two different terms I'm going to keep it kind of consistent here since I did post here in to matriculate on the right anterior interventricular so one of the branches that comes off of this coronary really really important one is the anterior interventricular artery this is probably one of the most important ones and the reason why is this artery is actually one of the most common arteries to get occluded by certain types of atherosclerosis and this artery is also referred to as the Widowmaker okay because if a clot if some type of actual either an embolism or some type of coronary atherosclerosis developing there it can include the blood flow to the actual surrounding myocardial which can lead to a scheming of the model car game and if the actual ischemia persists the tips you can become necrotic and die okay and this can lead to a myocardial infarction so very very important artery one of the most common ones to get occluded and lead to a very severe mi the other branch is called the circumflex the circumflex artery okay that's called the circumflex artery is kind of going to wrap right underneath the auricle okay right underneath the left auricle it's going to supply a little bit left H and a little put off part of the left ventricle now in general just in general cuz we already covered every aspect that these arteries will cover in our anatomy of the heart video two guys up and watch that watch that if I was you we cover the model we go through every single branch of these arteries and what part of the myocardium they support for right now we're just going to say that it supplies the myocardium that's what we discuss we said that its purpose specifically supplying the myocardium of the heart that is the muscle area so the marginal artery is coming down the rights of the heart and supplying the myocardium on the right side of the heart the posterior de matrícula artery supplying the myocardium on the posterior aspect of the heart so this is the actual model Khardung on the posterior aspect of the heart the anterior interventricular artery supplying a large amount actually supplying the interventricular septum it's applying a little bit of left ventral even a little to the right ventricle so this guy here is going to be supplying the myocardium also and then you have the circumflex which is applying a little bit of left the actual atria the left atrium muscle and it's even supplying some of the actual left ventricular muscle so this is going to be again supplying the myocardium now we were to be really particularly you guys now the arteries it's like we had circumflex artery it actually branches into smaller arteries called arterioles and then from the arterioles they go into these tiny little exchange vessels called capillaries so if you guys really want to be specifically could say left coronary artery goes into the circumflex artery which goes into the circumflex arterioles which goes into the circumflex capillaries and those capillaries are found in the myocardium of the heart okay so again circumflex artery branches into arterioles which branches into capillaries and those capillaries are the exchange vessels in the myocardium coming out of the myocardium you're gonna have these tiny little veins called venules those venules are going to come together and form decent-sized veins what are these veins call well let's go back in order again the vein that's actually drained myocardium that was supplied by the marginal artery this is a very important one this is called the small cardiac vein okay this is called the small cardiac vein so again remember arteries are different delivering blood away from the heart veins are taking blood back to the heart so now we're going to take this blood and we're going to try to bring it back to the heart so again marginal artery goes to the myocardium and it gets drained from the mono cardian by the small cardiac vein if you really want to be particularly venules and then the small cardiac vein okay over here post-independence going to be picked up by another type this is actually going to be picked up specifically by the middle cardiac green the middle cardiac li okay then anterior ventricular goes to the myocardium it's going to be during that myocardium from the answer to the tricular artery is going to be drained by the great cardiac vein so this is a dream' by the great cardiac vein then the last one the circumflex re are going to go to the myocardium provide the exchange and it's going to get drained by what's called the posterior vein of the left ventricle that's a weird one right but that's what they call it they called the posterior vein of left ventricle okay so real quick recap myocardium from the marginal artery is drained by the small cardiac demonic ardian which has come from the post interventricular artery supplied drained by the middle cardiac the myocardium that was supplied by the anterior interventricular artery is going to be drained by the great cardiac and the myocardium that was supplied by the circumflex is going to be drained by the posterior vein of the left ventricle now what's really cool is these veins are going to dump into one big old sucker big ol vein this big old vein is actually called the coronary sinus okay so this big old vein is going to drain into is called the coronary sinus it's a very very large vein and now what happens is when this vein gets the blood from the small cardiac vein the middle cardiac vein the great cardiac vein and the posterior vein left ventricle it takes up a lot of blood so what's going to happen is this coronary sinus is going to into that blood into one of the chambers of the heart now this is deoxygenated blood right because at the myocardium we're dropping off oxygen picking up co2 deoxygenated blood is found on the right side of the heart so what do you think this is going this is going to the right atrium and then from the right atrium it would go down to the right ventricle and then it would start to pulmonary circuit which already had a video on and then it would go get oxygen to come back to the left side of the heart and then get pumped to the next destination right so again real quick recap left ventricle pumps button to the blood into the ordered semilunar valve then from that into the ascending aorta that branches into the right coronary artery left coronary artery the right coronary goes to the marginal artery and the posterior ventricular these go to supply the myocardium by dropping off oxygen picking up co2 they are correspondingly drained by the small cardiac vein in the middle cardiac vein which empties into the coronary sinus the left coronary artery gives off an anterior interventricular branch and a circumflex branch which go to there recording myocardium and supply oxygen pick up co2 out of the waste products then they are drained accordingly by the great cardiac vein and the posterior band left ventricle which empties into the coronary sinus the coronary sinus now with all of this deoxygenated blood empties into the right atrium which goes down to the right ventricle and gets sent out to the pulmonary circulation to get reoxygenate 'add and the last thing I wanted to say again is this circulation you have to remember the myocardium of the heart is only getting that blood supply when the heart is in diastole which is the relaxation period if the heart is actually there you have an excessively high heart rate the heart will not be in diastole long enough for the myocardium to get that actual supply of blood so it's very important that the myocardium is a nice diastole period so they can get the oxygen it needs to continue to function properly iron engineers I hope all of this made sense I really do hope that you guys enjoyed it if you guys did please hit the like button comment down the comment section and please subscribe as always engineers until next time what I'm going to do now is I'm going to step out of frames that you guys can take can write down all of this actual diagram here for you guys on convenience okay take anything is 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