- so when most people think of the heart, they think about something like this. or love or valentine'sday, and that's all great. but what if you're a littlemore medically inclined, or scientifically inclined? well then maybe you thinkabout something such as the heart sounds, or lub dub. and i'm gonna give you a secondto put in your headphones because those will actually help you
hear these sounds better during the video. (heart sounds) and so you can hear thosenormal heart sounds. but what happens ifmaybe, when you visited your cardiologist, he orshe heard something extra while they were listening to your heart? well maybe they told youthat you have a murmur. and so keep those headphonesin because i'm gonna play you one of the more common murmurs.
(abnormal heart sounds) you'll notice that you actuallyhear the lub and the dub, but in the middle youactually hear this whishing or blowing sound. so what's a murmur? well, it's really pretty simple. it's actually just the soundof turbulent blood flow. and when we say turbulent, all we mean is the same thing that wemean when we talk about
a turbulent plane ride, rough. so it's the sound of rough blood flow through a cardiac structure. and in particular, we're gonnabe talking about the valves. and so this is a good time to remind you that we have four valves in the heart. and those are the mitral, the tricuspid, the aortic,
and the pulmonic. so when someone's toldthat they have a murmur, they automatically freak out. and that shouldn't always be the case because murmurs can actually be normal, or abnormal. and so normal murmurs arealso called functional, or innocent murmurs. and abnormal murmurs are alsocalled pathologic murmurs.
so you may be thinking,well how can a murmur be innocent or normal? well, let me draw you a picture here, and see if we can help explain this. so here we're just gonnadraw any normal valve. and so this would be a valvelike the tricuspid valve or the aortic value oreven the pulmonic valve. those all have three cusps, and so this is a trileaflet valve.
and so in a normal, or functional murmur, you simply have an increase in flow. and when we say flowhere, we mean blood flow. and so you really justhave a lot of blood flow through this normal valve. and that can actually causea little bit of turbulence and lead to a murmur. but the important point is that this valve is absolutely normal.
now in the abnormal murmurs, the valve is actually dysfunctional. and that is what's causing the turbulent blood flow and murmur. and so instead of it being nice like this, well maybe you have alittle situation like this. or maybe some of theseedges are scarred up or old, and not working correctly. and so now either not enoughblood can get through,
or blood can actually leakback when it's not supposed to. and so again, it's reallyimportant to know that in this case, the valveis what is abnormal. and so in abnormalmurmurs, the valve can be dysfunctional in one of two ways. and the first is that thevalve can be stenotic, where you can have asituation of stenosis. and the other is called regurgitation. and you'll also see this as insufficient.
and so the way i like to think about this, because i always usedto get them confused, is by using a typical high school. and so here we're gonna drawthe halls of a high school. and we're gonna usedouble doors as our valve. and so when the kids are still in class and the bell hasn't rungyet, these doors are closed. and no one's going in or out of them. now when the bell rings,students push open the door,
and if everything's working normally, these doors open very wide,just about all the way. and all of the students can get through, and they do this in apretty orderly fashion, and everything's kinda smooth,and everyone gets to go home. but what if these doorswere a little bit sticky, or maybe the hinges hadn'tbeen greased in a while? well now you get a situation like this. and so now when students try and get out,
they're kinda forced fromall over to get through this tighter space, and notas many of them can get out. and so there's all thispushing and shoving, and this is the picture of stenosis. in this case, we have a stenotic door, or in the case of the heart,we would have a stenotic valve. and so let me go ahead andlabel the normal conditions. so this is normally howwe want the door to open. so this is normal open.
and then this is normally howwe want the door to close. so this is normal closed. now let's talk about thesame thing for regurgitation, but in this case, we're gonna start with the normal open scenario. se let me draw these hallways again. so in the normal opensituation, remember these doors are all the way open. and we're gonna assume thisis a little bit later in time,
and so that the kids areactually a little bit further ahead here. and so the doors aregetting ready to close. now once those kids haveleft, we need the doors to close properly so thatno one else can get back in. and so normally these doors will close, and no one can get backin, even if they'd want to. and you'll see these are kindalike students coming back for after school activities,but they're not gonna be
allowed in because the doors are closed. now what happens if thesedoors become a little floppy? well now, let's say maybeone comes back to normal, but the other one overshootsor something like that? and the details of that are not important, but what is important is that you now have this little pathway throughwhich students can kinda get back through, but notmany, and there's still some pushing and shoving.
and so this is the case of regurgitation. and then we'll go ahead andlabel the normals again. and so this is normal closed. and this is normal open. and so what you reallyneed to remember from this, because it'll help somuch when you're trying to remember the differentvalvular diseases down the road is that stenosis is aproblem with opening. so this is an opening problem.
the valve, for some reasonor another, is stenotic, and it can't open enough,meaning not enough blood can get out. and so again, this is an opening problem. now regurgitation is kind of the opposite. and so this is a closing problem. now the valve, for whateverreason, is regurgitant, and can't close all the way. and so now this cancause back leak of blood,
and again, this is a closing problem. so you can imagine thatif we're having problems opening valves or closingthem in the heart, that we can actually get somesigns and symptoms, such as fatigue, and then you cansee this guy laying down and not feeling so well. shortness of breath, andyou'll see i've drawn you a little pair of lungs herethat's just a little too short. and finally swelling, andthis is usually swelling
of the extremities, such as the feet. and so these are somegeneral signs and symptoms that would be associatedwith valvular heart disease.
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