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Current time:0:00Total duration:9:02

Video transcript

if you look at the top of the screen you'll see that I've drawn you these two diagrams and if you'll notice they're actually a little bit different in terms of which valves are open and which valves are closed and so these are great diagrams to demonstrate systole and diastole and so what I first want to do is remind you of the heart sounds which are s1 and s2 and if you remember between s 1 and s 2 we have systole and then between s 2 and s 1 we have diastole and we'll finish that over here just to kind of remind you that this is a cycle between systole diastole systole diastole and so in this diagram right here the heart happens to be in systole and you can kind of notice the relationship between s 1 here and systole and if you remember the heart sounds are actually caused by the closing of valves and so the mitral and the tricuspid have actually just closed and then when the aortic and pulmonic labeled a and P here open that will start systole now in diastole in this diagram we kind of have the opposite situation so now the aortic and pulmonic valves are closed but the mitral and the tricuspid labeled m and T are now open and so if you remember s2 is caused by the closing of the aortic and the pulmonic and so that will occur just before the mitral and tricuspid open as seen here and when those valves open you're in diastole and so I want to give you this logical algorithm to figure out what's going on in a patient with a murmur so the first question that you want to ask yourself is is there a murmur and if the answer to this is yes then we move on with more questions so if there is a murmur the next question is when does that murmur occur so when and the obvious answer to that would be well it's when I listen to the patients with my stethoscope but we need to get a little more specific is it in systole or is it in diastole well how do we figure that out so a good method for this is to actually use s1 and s2 because remember we showed at the top of the diagram up here where my cursor is that systole is between s1 and s2 well what if the patient's heartbeat is really fast and it's kind of hard to tell which one is s1 or s2 well then you can use something like the radial artery and so you can take a radial pulse on the patient and every time you feel their artery tapping up against your finger that corresponds to systole or the ejection phase of the heart and so what's closest to that beginning of systole well s1 is closest and so you'll know that the sound that you hear right when you feel the pulse tap your finger should be s1 so now if you determine that this is in systole the next question is going to be what valves are normally open during systole and what valves are normally closed so let's go ahead and answer those questions in systole and you can use the diagram above what valves are normally open well the aortic is normally open the pulmonic is normally open and the other two are closed so that kind of answers this question well what's normally closed the mitral and the tricuspid and so since stenosis is an opening problem and the only valves that are open during systole are the A&P or the aortic and pulmonic that means these two valves in order to give you a systolic murmur would be stenotic and will rights enosis here because you would have a order or pulmonic stenosis on the other hand the only valves that would be closed during systole would be the mitral or tricuspid and so since regurgitation is a closing problem for the valve this would be regurgitation and so just to reiterate this means that if we have a systolic murmur we have one of four choices based on which valves are open and closed this same thing can happen in diastole and we'll ask ourselves the same questions so which valves are open during diastole well if you look at the correct diagram at the top of the page the mitral and the tricuspid are open here and which valves are closed the aortic and the pulmonic are closed during diastole and so for the same reasons that we just described before since stenosis is an opening problem that means that here you would have mitral or tricuspid stenosis and here you would have a aortic or pulmonary Gurjit ation so you may be thinking okay well now we have four possible choices well how do I figure out which murmur it actually is so let me scroll down here and give myself a little more space the next step is to really consider location so if you've ever been to the doctor and you watch them while they listen to your heart I usually put the stethoscope in at least four different places and if you look over here I've drawn a sternum and some of the ribs that go with the sternum to give you an idea for where to listen with the stethoscope and so one of these locations is in this second intercostal space meaning the second space in between ribs and this is called the aortic area and other people will also say the right upper sternal border and that's kind of pretty self-explanatory this is the right side of the patient so right side left side then this would be the right upper sternal border another location is again in the second intercostal space but now it's on the left side and so this is the pulmonic area and this is also known as the left upper sternal border the third place where you usually listen is here and so this is the fourth intercostal space and this is called the tricuspid area and finally if you haven't realized we're pretty much giving each valve its own area so the last one is the mitral area and this is in the fifth intercostal space but you'll notice it's a little more to the side of the other ones or lateral to the other ones and the anatomic description of that would be the fifth intercostal space in the mid clavicular line meaning if you drew a line from the midpoint of your clavicle or your collarbone down your body in a longitudinal fashion so straight up and down that it would intersect with this point at the fifth intercostal space so what I want to do is quickly take you through an example of this algorithm to see that this can actually be pretty logical and easy so take a second and listen to this murmur and if you're having trouble hearing this on just your computer go ahead and plug in your headphones and it'll make the sound a lot better so the first question is is there a murmur well duh we just heard it now is it in systole or diastole so let me replay you that murmur again but a little bit slower now you'll realize that you actually hear s1 and s2 and then in the middle you kind of have all this stuff or this this blowing sound so what can we say from that well we know that systole is between s1 and s2 so this is a systolic murmur now with our knowledge of what's open and what's closed we have choices between a or tech implement exposés and mitral and tricuspid regurgitation so now if I told you that you actually heard this murmur in the mitral area that pretty much gives it away and so this murmur was that of mitral regurgitation now there are other ways of confirming or identifying which specific murmur it is such as the shape and intensity of the sound and other features but those are a little more advanced