The ECG Course - Atrial Rhythms

hello and welcome back to the ECG course this is chapter eight in this chapter we're going to talk about atrial rhythms atrial rhythms in the first chapter we talked about sinus rhythms we said originate from the SA node in this chapter we're talking about atrial rhythms which originate from anywhere in the right or left atria the right or left atrium except for those rhythms that originate in the SA node okay so let's uh let's take a look now with sinus rhythms we noticed we have a P wave it's a regularly regular rhythm it's within 60 to 100 beats per minute you have a normal PR interval and you have a normal QRS width but also a few things that make it sinus are that you should have an upright P wave in all of your limb leads except for AVR and sometimes AVL so if this was lead to okay if we were looking at lead to we go back we were looking at lead to here and we saw these negatively deflected P waves they're inverted okay we would say that this is not a sinus rhythm it's some other ectopic foci since there is a P wave we know it's coming from the atrium so it is an atrial rhythm sometimes we call it an ectopic atrial rhythm okay it looks like it's a sinus rhythm in every way except for a negatively deflected P wave in an inappropriate lead we'll talk about that a lot more in 12 leads when we're looking at all the leads together okay ectopic atrial tachycardia does not have to have a negatively deflected P wave it might be negatively deflected but it doesn't have to have happen you know it occurs because of these rules your rate is going to be between 100 180 beats per minute all right your rhythm is regular your p-wave is present but it will be different with the tachycardia okay so this P wave will be different from this P wave that's how you know it's an ectopic atrial tachycardia because if it was a sinus tachycardia it would have the same shape throughout all right the PQRS ratio is still going to be one to one you have one P wave for every QRS complex your PR interval is still going to be normal okay and it's going to be a different PR interval with the ectopy so the spacing alright let me bring in my calipers here the spacing here for this PR interval is going to be different then over here the tachycardia is going to have a different PR interval that's how you know it's an ectopic atrial foci and all that means is that somewhere else in the atria and either the right atrium or the left atrium is causing the polarization to take over in a different area of the heart your QRS width is still going to stay narrow it's going to be less than 120 milliseconds which is three small boxes so topic atrial tachycardia alright the next arrhythmia we're going to talk about is wandering atrial pacemaker and multifocal atrial tachycardia so these are both this sort of the same concept what happens is you'll have all these different atrial foci for instance you'll have the atrium will do polarize for over here alright and cause the tricular polarization to occur and then the next beat it might occur over here and then cause matriculated polarization occur and then over here and cause ventricular depolarization to occur so it's again it's not a sinus rhythm because it's a different part within the atria that's causing the de polarization all right so here's a better example of what I was trying to explain you'll see that the first QRS complex is coming from atrial focus in the right atrium there it's still in the right atrium here but it's a little further down and then over here it's you know close to the atrial septum and then over here it's in the left atrium alright doesn't always occur in that pattern but you'll notice that your p-waves will change with every change of those different foci so wandering atrial pacemaker here are your rules it's less than 100 beats per minute that's an important rule it'll be less than 100 beats per minute the rhythm is going to be irregularly irregular you'll notice that this rhythm is going to change it's not going to stay consistent like it does with a normal sinus rhythm okay if we map those out does not stay consistent your P waves you should have at least three different morphologies and all that means is you have to have three different shapes of P waves if you look at these P waves down here you'll see that they do not look like at all okay they constantly are changing shape alright that has to be true with a wandering atrial pacemaker your PQRS ratio is still going to remain one to one there's no extra P waves with these arrhythmias your PR interval is going to be variable it's going to change one PR interval but might be you know let's say 140 milliseconds the next might be 150 milliseconds and so on and so forth and your QRS width should stay normal it should be narrow less than three small boxes point 12 seconds multifocal atrial tachycardia is exactly the same as wandering atrial pacemaker except the rate is greater than 100 that's the only difference so that's why with W AP the wandering intro pacemaker it's so important to remember that your rate must be less than 100 beats per minute with ma T multifocal atrial tachycardia your rate must be greater than 100 beats per minute and then it has all the other rules the same it's irregularly irregular okay if we measure these are our intervals you'll see that it's a regular the p-wave must be at least three different morphologies your peak to QRS ratio should it be one one your PR interval will vary and you're curious width should be narrow so those are two arrhythmias that are very similar to each other here's an example of multifocal atrial tachycardia because this one's obviously faster than 100 beats per minute you'll notice the P waves are rapidly changing you have at least three different P wave morphologies you don't have any extra P waves your PR intervals are changing on on this EKG and your QRS complexes are narrow alright so this would be considered a multifocal atrial tachycardia this one's ma t because it's faster than 100 beats per minute and again it's very irregular if we measure that out it's very irregular okay it's very regular your P waves if you look at those things they're all different shapes and your PR interval is constantly changing this is a multifocal atrial tachycardia here's another example of multifocal atrial tachycardia and remember W ap wandering actual pacemaker looks exactly the same it's just slower than 100 beats per minute alright now you might be saying well I don't see P waves over here I don't see any P waves okay now right there you're right you can't see the P waves and the reason you can't see because the rhythm is too fast but it's very unlikely okay since all the QRS complexes are the same that's really changing anything other than the atrial focus alright you do have a P wave here alright it's in that t way we talked about that before the same thing happens here it's in that T wave that's that extra bump it happens over here to that little bump is the P wave and the fact that this is so irregular kind of indicates that this is possibly a multifocal atrial tachycardia all right moving right along to atrial flutter now atrial flutter is a much different type of tachycardia this is considered reentry tachycardia and what happens is somewhere in the atria alright a lot of times it happens like this okay you will have the polarization and then that the polarization will stay in this reentry and it usually occurs about 250 to 300 times per minute that's pretty dang fast so those eight rate of atrial are two polarizing really fast they're two polarizing about 250 to 300 times per minute way too fast to sustain life now every so often the ventricles will take that to polarization and continue it down into the ventricles hopefully not 300 times per minute because that is way too fast to live alright so here are the rules again the atria under polarizing really fast this is 250 to 350 times per minute the ventricles 125 to 175 times per minute but potentially they could be two polarizing faster than that the rhythm is usually regular the P waves are sawtooth F waves I'll explain that in a second called flutter waves or F waves your PD QRS ratio will vary not usually on the EKG rhythm itself but it depends on which EKG you're looking at for example this one we would call right here a two-to-one atrial flutter what that means is we have two flutter waves okay for every QRS complex so we call this a two-to-one atrial flutter now this line here this B line down here is showing us this rhythm without the QRS complexes so the bottom rhythm is just the top one without the QRS complexes just to show you that sawtooth F wave pattern alright that sawtooth pattern is easy to see sometimes when you cover up those QRS complexes you can see that sawtooth pattern and identify atrial flutter I promise you that this quick little lesson is not going to give atrial flutter the justice it's due when we start looking at a bunch of 12-lead examples you're going to see why the PR interval is variable and the QRS width is less than 120 milliseconds usually now with atrial flutter the ventricular rate the heart rate is going to depend on that ratio we talked about now whatever your atria depolarizing at for instance if these atria are polarizing at 300 times per minute down here which is very common since this is a two-to-one flutter it would the heart rate would be exactly half of that atrial rate okay so if the atria too polarizing at 300 times per minute then the heart rate for a two-to-one flutter would be 150 times per minute 150 beats per minute so that's very common so I'm just quickly showing you this atrial flutter rhythm but we're going to have to revisit it because it's such a difficult one for a lot of people to identify and here's why a lot of times people especially with these two-to-one flutters they'll see this first one here as a T wave and then this one is a P wave and they'll think it's a sinus tachycardia that's very common to think that but it is an atrial flutter in the way that you identify it is by looking at many many examples and noticing that you have to cover up those QRS complexes sometimes and see that sawtooth pattern here's a good example of atrial flutter now this one is a little bit slower as far as the ventricular rate okay and the PQRS ratio we have one two three this is considered a four to one atrial flutter you have four flutter waves for every QRS complex and again if you cover up those QRS complexes sometimes it makes it easier to see that sawtooth pattern another important concept to remember is that the flutter waves will go right into and continue through the QRS complex and the T wave okay so they don't care about you know what's happening in the ventricles they'll just keep occurring in P waves generally if the P wave is causing the QRS complex you won't see it go into the QRS complex with a sinus rhythm or something like that here's another example of atrial flutter and again it's important to look at many examples of these because they're hard to identify alright and you'll see that this one has what we call a variable ventricular response what that means is that you have a 1 2 3 2 1 atrial flutter here and then right here okay you have maybe a 2 2 1 alright so you have a varying ventricular response a variable ventricular response this is the same rhythm across the bottom in a different lead okay notice how different it looks I wouldn't monitor in this lead because the ventricular activity is so small I would monitor in this lead up here because you have nice big QRS complexes that's an important concept to remember when you have a patient on the monitor don't choose the lead with the smallest QRS complexes and the most artifact change your lead until you have one that kind of shows you the best example of the rhythm a lot of people forget to do that here's another example of atrial flutter and a lot of people might miss this one thinking that you know we have our t wave here and our P wave here but if you continue this one right there you can see if we draw them in that this is an atrial flutter all right this in fact is a three to one atrial flutter those typically occur around 100 beats per minute when you look at the heart rate here's another example of atrial flutter and again you would have to continue that F wave that's hidden in there that's what Macy's so - identifies these F waves will just become hidden alright sometimes you have to look at them upside down if I flipped this you could see this sawtooth pattern a little bit easier alright then covering up the QRS complexes sometimes so that's another example all right our next atrial arrhythmia is atrial fibrillation now this is a common occurrence and cardiac patients especially you know the elderly any elderly patient that tells you that they have an irregular heart rhythm it's possible if they have atrial fibrillation check and see if they're on blood thinners check and see if there are negative Crona Tropes if they're on drugs that slow down the heart those are common medications for atrial fibrillation all right atrial fibrillation is caused by a fibrillating or fibrillating atria basically they're quivering alright the atria are quivering they're not really depolarizing fully the way they should they're too polarizing close to 800 times per minute which is not sustainable with life if you do polarize the ventricles that often all right in fact we call that ventricular fibrillation which we're going to learn about later so the atria are quivering so that it doesn't typically have you know pacemakers that are just randomly occurring in fact if you think about it that way it might help but really it's just an entire atria are just constantly quivering sending signals down to the ventricles almost 800 times per minute and hopefully the ventricles are only picking up some of those and this is what it looks like you you sometimes will have what we call a fibula Tory wave all right instead of P waves or sometimes it's completely flat you don't always see if they're boat or e wave all right but you notice how it looks like artifact but the big giveaway here is that you can't really truly identify any P waves there are no P waves with atrial fibrillation the rate is going to be variable okay it's going to depend on the ventricles and how the Mitchells respond to that chaotic atrial rhythm all right there is no true rhythm all right it does not maintain a normal rhythm at all it is a regularly irregular alright it is the most common irregularly a regular rhythm you will see so again there's no P waves you have chaotic atrial activity if any that you can see on an EKG there's no P wave so there's no PQRS ratio there's no P wave so there's no PR interval and York us width should make a stain arrow less than three small boxes okay since afib is such a common arrhythmia I'm going to show many examples of this taking a look here you cannot identify any there's no clearly identified P waves it's an irregularly irregular rhythm with narrow QRS complexes it's a fib say no more here's another one let's take a look at the rate of this one's 1 2 3 4 5 6 7 8 9 10 about 100 beats per minute controlled a fib will typically be close to 100 beats per minute rapid afib will exceed 100 and it becomes a needy of treatment depending on the patient's condition okay again we have here a febrile Tori wave we don't have any clearly identified P waves and the rhythm is irregularly irregular you don't even have to get out the calipers for this one it's obviously a regular take a look at another one you see the top rhythm here it doesn't have any obvious artifact looking way but doesn't have a fibula Tory wave the bottom one you can see in a differently that it does have a purgatory wave it's an irregularly irregular rhythm it's narrow it's a fib again very very common arrhythmia especially amongst the elderly here's a fib again this one's a little bit slower 1 2 3 4 5 6 7 8 that's very controlled okay we don't have any idea clearly identified key waves it's irregularly irregular and narrow we got to call it a fib that is it for this lesson I tried to make it a little bit quicker than the last one we still reached about 20 minutes okay if you want to go back and look over sinus rhythms again click on the left image it will take you back to chapter 7 on sinus rhythms if your regular ready to move on to the next chapter chapter 9 we're going to start talking about junctional rhythms okay and if you haven't subscribed yet click that subscribe button on the bottom and make sure you're getting all these videos

Channel: The Resuscitationist

Views: 167,784

Keywords: ECG, Cardiology, Paramedic, EMS, Prehospital, EKG, 12-lead, arrhythmia, clinical, emergency, emergency medicine, EMT, advanced life support, ALS, P101, paramedicine101, meducator, ER, CEU, CME, drug math, clinical education, medicine, ambulance, trauma, medical, electrocardiogram, ETCO2, capnography, premed, med student, medical school, physician, axis determination, meducator01, adam thompson, EMT-P, nurse, RN, LPN, CEN, board review, education

Id: FtGiphQBuaI

Length: 20min 27sec (1227 seconds)

Published: Sun Jan 05 2014