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Current time:0:00Total duration:14:39

Systolic murmurs, diastolic murmurs, and extra heart sounds - Part 2

Video transcript

so the last systolic murmur or sound that I want to talk to you about is mitral valve prolapse and this is pretty much exactly what it sounds like the valve actually prolapses or billows into the left atrium and so this causes a click and so this is a click that's kind of similar to the one that we talked about in a or text enosis which was an ejection click but this is a click that's not associated with ejection of blood through a valve and so this is really a non ejection click and it's also not right at the beginning of systole it's actually a mid or mid to late systolic click and so you'll see I've labeled that for you there and what causes that is as the left ventricle begins to contract remember this would make the mitral valve closed to cause s1 so the valve closes normally not like what's shown in this picture closes and causes your s1 and then as the pressure builds this valve will actually accelerate into the left atrium and when it stops abruptly because it's held by or should be held by these chordae tendineae here then there's this rapid tensing of either the chordae or that leaflet and that causes this little click now this condition is also associated with mitral regurgitation and so you can imagine if this valve kind of billows up here there's probably some problems closing and maybe it doesn't close completely correctly and so you can get blood flow in here and if that's the case then after the click you're going to have the murmur of mitral regurgitation and so you'll get this and so I want to make a point here I've seen some textbooks that show that this is a flat murmur and others that say that it's a crescendo murmur for our purposes here we're not going to dwell too much on the shape of the murmur following the click but what's important is the click itself because the click a mid-systolic click is virtually diagnostic for mitral valve prolapse so overall this is described as a mid-systolic click with a late systolic murmur and then it's like mitral regurgitation is heard best at the apex or the mitral so now that we're done with systolic murmurs let's move on to the diastolic murmurs so now that we're going to talk about diastolic murmurs I'm going to switch my pen color here to green and we're going to move on to the first diastolic murmur and that's going to be a or tic regurgitation and so we know that this means that blood is going to be coming back through the aortic valve when it's supposed to be closed and so for aortic regurgitation this is a little counterintuitive because you would think maybe a or t'k would go to the aortic area but because this blood is coming back this way we're actually going to listen for this kind of in this area and so this wasn't really one of our defined areas but we're basically going to say along the left sternal border meaning on the left side of the sternum and the reason is because the Bloods flowing the other way so why would you listen in the normal aortic area when the Bloods going to be traveling the other direction and so this time because we're talking about diastolic murmurs these murmurs are actually going to occur between s2 and s1 and so let's talk about s2 for a second s2 is actually going to be caused by the closing of the aortic valve and then soon after that the mitral valve will actually be open and then the heart's in diastole meaning it's filling with blood but because this is a or decree Gurjit ation that means there's a closing problem with this aortic valve and so blood right when this tries to close because the pressure will actually be greater here then here right at s2 blood is going to be coming through here but blood is also filling the ventricle from the atrium and and so the pressure this little P is actually going to start to get a little bit bigger and so at the beginning when the pressure is still little a bunch of this blood is going to come back through the aorta and so you get this very intense part of the murmur that I've drawn and as that pressure gets a little bit bigger in the ventricle then this is kind of kind of diminish and this is the shape that you actually get with aortic regurgitation and this is called an early diastolic murmur it's happening in the beginning of diastole and its shape is d crescendo and just to mention the right-sided condition a pulmonic regurgitation would be the same type of murmur an early diastolic decrescendo murmur but this time it would actually be heard along the upper left side of the sternum whereas this one was kind of generally just along the left side of the sternum so the last murmur that I want to talk to you about is mitral stenosis so now that mitral valve is having trouble opening and because the mitral valve is open during diastole this is also a diastolic murmur so if we start at s2 again remember that's the closing of the aortic valve and that would be here what happens just milliseconds after that is that the mitral valve should open and it does this to fill up the ventricle in diastole and so instead of a nice big opening we kind of get this tiny little opening then we're going to show like this and so in the beginning of diastole you actually have the most blood coming from the left atrium through to the left ventricle and this is known as rapid filling so the ventricle actually fills up with more blood in the beginning of diastole than it does at the end and that's due to a pressure difference meaning throughout diastole the beginning of it is where that pressure difference between the atrium up here and the ventricle down here it's when that pressure difference is actually the highest is the beginning portion of diastole and so at the beginning portion you're going to have the most intense part of that murmur but before that happens we have to talk about this extra sound that we may hear and so right after the aortic valve closes the mitral valve is going to open but because this valve is stenotic when it's about to open the leaflets can only just open a little bit and they kind of snap open and so this is an opening snap and this is kind of similar to an ejection click in the systolic murmurs but in diastole this is called an opening snap and it's from these stenotic valve leaflets shooting open during the rapid filling phase of diastole and so what you get is just milliseconds after s2 you get an opening snap OS and then like I said because the pressure difference is greatest during this rapid filling time you actually have the highest intensity of the murmur here and then it starts to slow down as the pressures become a little more equal and then finally what happens at the end of diastole is that the atrium actually gives a little contraction to push any leftover blood into the left ventricle and so we're going to show that like this and it's going to push any leftover blood into the ventricle and that's going to give you this little upslope like this little extra kick at the end and so this is called pre systolic right before systole accentuation which is really just a fancy word for getting bigger pre systolic accentuation and so this murmur is heard in the mitral area or again like some people like to call it the apex or apical area and so the way people describe this murmur is actually an opening snap followed by a mid diastolic Rumble and people say this sounds like a rumbling sound and it's also kind of because that murmur is a weird shape you see how it kind of goes down and then comes back up and so they say an opening snap followed by a mid diastolic Rumble and just to mention the right-sided valve condition tricuspid stenosis this would produce the same murmur an opening snap followed by a mid diastolic Rumble but instead you would hear this in the tricuspid area and so the last thing that I want to talk about are extra heart sounds and so whether you've realized it or not we've actually covered two types of extra heart sounds already one of them being the click and remember this can be an ejection click or a non ejection click the ejection one being associated with aortic stenosis and the non ejection one being a little bit later in Sicily and being associated with mitral valve prolapse the other extra heart sound that we've covers the opening snap and remember that's associated with mitral stenosis the other two really important extra heart sounds that we're going to talk about are what are called s3 and s4 and so you'll realize that we have s1 here s2 here so these are the next two heart sounds but generally when these are present it's not a good thing so s3 and s4 are really not murmurs they're just another sound it almost sounds like another s1 but just in a different location or another s2 and in a different location and so these are actually heard best in the mitral or apex position here but specifically if you have the patient line in what's called the left lateral we're going to abbreviate that lat decubitus position two-qubit cysts and all that really means is that the patient rolls over to their left side and the physician or the nurse or whoever's taking care of you will listen with their stethoscope in the mitral position and the reason for this is just that it brings the heart closer in position to where the actual stethoscope is going to be when you roll over your heart will shift a little bit and actually come closer to the ribcage so what causes this s3 and s4 well s3 is classically a volume overload condition and so you hear this in early diastole so around here and this occurs during the rapid filling phase during diastole that we talked about before and so in this rapid phase if you have too much blood too much volume this ventricle is going to fill up really quickly and what happens is you get a tensing of these strings or these chordae tendineae here and that tensing actually causes the s3 sound so quickly again it happens in the rapid filling phase of diastole due to the tensing of the chordae tendineae when all that volume fills up the left ventricle and so in kids or adolescents and we'll kinda just right young here an s3 can actually be present but that's usually normal and this kind of just means that the heart is capable of taking extra volume and expanding and you'll still hear that sound but it's a normal condition but in a middle-aged or old person or that's not very nice an elderly person this is usually a bad thing and it's usually due to heart disease something like congestive heart failure where they have too much volume coming into that ventricle and you get an s3 and there are many other conditions that can cause an s3 but for our purposes let's just know that it's related to volume overload so s4 is a pressure overload problem and what happens is when the heart has to contract against increased pressure so let's kind of just say that maybe there's increased pressure here greater than the normal amount so let's say maybe in a case of high blood pressure the heart is contracting against this increased pressure and over time the heart is going to actually hypertrophy or increase in size but this is actually called concentric hypertrophy meaning the muscle increases in size but inward and so it actually makes this ventricle really stiff and so the s4 sound is what you hear when the atrium remember that the atrium at the end of diastole contracts to get that last little bit of blood out and so the s4 is what you hear when the atrium contracts into a very stiff ventricle and so this sound occurs at the end of diastole just before the next cycle of systole is going to take place and I'm not sure if we mention this but s4 is also heard in the mitral area and best heard in the left lateral decubitus position and so if you'll notice both of these sounds are in diastole just different parts of diastole and so other common names I should probably tell you so that when you hear them you're not confused or that people call s3 a ventricular gallop remember this is a large volume of blood coming in and tensing those Corday in the ventricles and people call s for an atrial gallop and that's because this sound is really caused by this atrium contracting into the stiff ventricle and so the s4 is always pathological meaning it's always bad news and so I'm going to run you through that original montage of heart sounds and murmurs and let's see if you can figure it out I'm going to put up a label of which murmur it actually is towards the end of each individual murmur you you you