Transcript for:
Understanding Blood Flow and Heart Valves

[Music] blood flowing through the heart so here's that Superior view of the heart on the left side of the screen with the Atria removed and then this here is an anterior view of the heart on the left side so the heart valves work together as one-way valves to make sure blood is Flowing properly through the heart when the ventricles are relaxed blood is flowing in the atrium from The Atrium through the open heart valve down into The ventricle but the heart valves leading out of the ventricles in this case in the picture the a Arctic valve but it's also the same for the pulmonary semi lunar valve so when the ventricles relax blood is flowing into The ventricle and the atrio ventricular valve is open but the other valve leaving out into the artery is closed and that allows The ventricle to fill with blood without that blood escaping out into its artery we can see over here this is a real picture on the bottom left this is that aortic semi lunar valve right here okay however when the ventricles contract those atrio ventricular valves all right the pressure builds up and slams The atrio ventricular valves closed but the ventricles contract with so much force that without the cordi tendine and the papillary muscles here the cusps of the atrio ventricular valves would get pushed upward into the atrium and blood would flow backwards the wrong way up into the Atria so Contracting ventricles also we get the those papillary muscles Contracting Which pull in the Cordy tendon e which help prevent the cusps of the atrio ventricular valves from going too far backwards and causing a backf flow of blood but the valves the aortic semilunar valve and Pulmonary semi lunar valves they are built to open up when the ventricles contract so the blood gets forced out of The ventricle out into their artery because the valve freely gets pushed open by the blood but the atrio ventricular valve stay shut preventing the backf flow of blood there are some diseases that you can get with your heart valves themselves so any kind of problems that you have with your heart valves generally that's referred to as heart valve disease um there are various factors that can cause heart valve disease so you can see here on the left um they're more common as you age there are genetic components to it so it could it can run in in the family various types of what we call metabolic risk factors those are things like you know having diabetes having really high levels of atopos in the body having um your having bad having too much bad cholesterol LDL cholesterol so various um conditions like that you know certain kinds of infections Medical Treatments not having very good lifestyle habits like smoking and drinking all the time not exercising enough there are many many different aspects are contributing factors to these heart valve diseases and sometimes it's just when the when the the embryo and fetus is developing those heart valves don't quite develop correctly and so you're it's born with a defective heart valve we'll call that A congenital Mal formation so congenital means you're born with it and the heart valve never formed correctly in the first place that's a congenital Mal formation there are two basic types of ways that heart valves can be um cannot work properly there's stenosis and regurgitation now in stenosis what happens is the heart valve doesn't open properly it doesn't open all the way so if you look down here in this picture right when a heart valve pops open it should be have a nice big opening for plenty of blood to flow through it with a stenotic heart valve if you have stenosis of a heart valve then it it can close pretty well but it doesn't open up all the way so you're getting less blood flowing through the valve either into the ventricles or from The ventricle out into the artery depending on what the valve is the other issue that we have is regurgitation so with regurgitation that's the opposite problem of stenosis in regurgitation the valve can can open properly but it doesn't close properly so then you can get with regurgitation you can get the blood flowing backwards or regurgitating going the wrong direction backwards um because it doesn't close properly it's partially open instead of sealing shut completely and the blood goes a little bit of the blood goes backwards regurgitation now stenosis both of these can be caused by many different reasons are many risk factors for stenosis and regurgitation but generally stenosis is caused by things like calcification of the heart valves so so calcium ions get deposited on the heart valve and it makes it too stiff because it gets calcified and then it just isn't able to open all the way because you get this calcium buildup on the valve it could be congenital so birth effects it could be from different kinds of genetic diseases causing stenosis or depending on how a heart valve gets damage certain types of damage to the valve could prevent it from opening properly or causing stenosis so things like inflammation of the heart valves May prevent it from opening all the way certain types of infections can damage the heart valves Medical Treatments like certain kinds of drug treatments or surgery heart surgery that could damage the heart valve or you know radiation treatments so certain types of Medical Treatments can also damage the heart valves for regurgitation it can happen due to prolapse which I will discuss in just a minute again certain types of birth effects and genetic diseases can cause regurgitation of a heart valve certain types of infections heart attacks can damage the valve in a way that or damage that valve or the surrounding muscle in a way that causes regurgitation and hypertension hypertension is chronically high blood pressure if you cannot get your blood pressure under control and it stays too high for too long and high blood pressure high hypertension can also damage the heart in a way cause cause regurgitation so sometimes when the heart valve either doesn't open properly or doesn't close properly either way you get it you get these weird abnormal heart sounds normal heart sounds are ldub ldub the heartbeat right ldub ldub ldub every time the heart beats you can hear it with the stethoscope so those are normal heart sounds the normal heart sounds are caused by these heart valves slamming shut during a heartbeat anything other than ldub is an abnormal heart sound that we call a murmur now there are different causes for murmur or abnormal heart sounds a common cause of a heart murmur though is regurgitation again the valve doesn't close all the way and so some of the blood leaks backwards the wrong way during contraction and it creates sort of like a hissing or a whoosh kind of a sound and that's that some of the blood squirting backwards the in the wrong direction there are murmurs that are what they call innocent though an innocent murmur is just an abnormal heart sound other than ldub but there are no problems it's just a a weird sound that your heart makes like sometimes the the septum of the heart sometimes the septum kind of vibrates and creates a weird noise but the septum is okay it's just it in an abnormal heart sound so prolapsed valve again a pro prolapse of a heart valve can cause regurgitation when a heart valve prolapses this often happens with the mital valve here the left atrial ventricular valve um when the cusps of the valve slam shut it should be roughly it should get pushed up to this red line but with a prolapsed heart valve the cusps of the heart valves get pushed backwards too much and it starts to protrude up into the left atrian so when that happens the custle of the valves get pushed backwards a little bit into the left atrium they don't form a nice tight seal and blood from the left ventricle when it contracts instead of going out into the aorta alone blood moves through this little opening between the cusps of the valve and squirts back up into the left atrium so this is a a valve prolapse it causes regurgitation