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and I'm sure. And so Oh, hi, everyone. Thanks for coming and see if I am content on one of the chemical fellows in medicine down in Cornwall. I've got a particular interesting cardiology which really have developed over the past couple of years from working and severe. And I were talking a few moments ago. What? We're waiting for people to join on. It can take a bit of time. I think when you graduate and start working to realize what you want to do. But it is really nice when you start to bring together the ideas of what you enjoy most and put that in. So what, you're going to do a work in the long term. So yeah, so it's a bit about me. Um, I've just actually come off a three month rotation in cardiology, working mostly on coronary care. So a lot of what I'm talking about come straight from what I've experienced on, but if not from my experience, from very rigid guidelines, So without any further delay, I think probably get started there. A few people just joining. But the first couple of slides are less critical, so we'll get started. So that we can finish on time. So what we're gonna talk about? Well, going to talk about the basic physiology of cardiac electrical conduction on when I was put in these two slides together, These stories too serious together. I've got elected today and tomorrow. I wanted to make sure I hit content that was clinically really relevant. Came up a lot, and exams on was sort of generally very, very useful to be aware off whether or not you want to do cardiology or not, Um, electrical conduction on a very basic level will really help with understanding the pharmacology, the physiology, E c. G. So we'll go through some really basic stuff on that on. Hopefully, it'll be a bit luminant in, if not a reminder. I'm going to try and give you a bit of a framework for organizing arrhythmias. I think there's a lot to learn in cardiology, as there is in most of medicine, without having a rough way of splitting that information up. It's very difficult to memorize all of it or memorize it. Well, so we'll be doing that. Um, we're going to talk a little bit about arrhythmia management. Um, ever sort of push from my electric tomorrow I'm going to be talking about a F and bradycardia is so if you want to know the other half of what we're gonna be talking about, please attend that. But this is a standalone lecture on its own things. I'm not going to talk about VF forces, uh, HVT, a Sicilian pa. That's because these things are covered quite well in BLS. And a less course is to work in the UK You as an F one or two progress through to have to You do need to complete those courses. So rather than covering something that you're going to get some fantastic teaching on, I'm going to fill in some areas that you may get less teaching. Um, so let's get started. So I thought we'd open out with a question that I worry very similar questions. This I got this on my MRC people. What one last year? So it does come up. Maybe we can just start with this one Sophia, and see how people go. So which part of cardiac conduction is the fastest? Um, we're going to see how long it takes you guys to answer Will probably give you about 40 seconds or until about 70% of people have responded. Just so we've got time to get through everything good to see. Some people are still coming in. Perfect. Okay, so it got real split down. We really between a be on a, which is kind of the point of these questions, Really. I think if you're over writing, teaching or preparing teaching, you don't want the questions to be so easy that everyone gets the right answers. On the correct answer is the back injury fibers. So why is that the case? Well in cardiac conduction, in order for the electrical signal to travel from the top of the heart down to the bottom, you actually have your sinoatrial node where the signal is it initiated. That passes through the atrial muscle down towards the Atrioventricular node, where it's temporarily halted before being conducted down the bundle of hiss and then on the back injury fibers. That's really important that the package E fibers these long strands that sit at the bottom of ventricles are the fastest part of conduction because that allows for your rapid ventricular contraction, which ultimately creates your BP and forces but around your body. So, um, so thinking about it like that is really important. And I just thought that was a nice way to open up this talk. So moving on a little bit, going from this sort of physiology at that level to moving on to how E. C. GS demonstrates some of that in the real terms on, I think understanding STDs is quite difficult thing to do, even if you've seen a lot and there's a way of spotting pattern recognition and if you don't want to be a cardiologist's very easy to learn some rules and get to the right answers. But I do think understanding it is really helpful. Um, so one way I was taught it, which I've always remembered, which works very well for me, which I'm hoping will rub off on to you guys is to think about the E. C G stickers, the leads that are attached to somebody's chest as listening ears that listen along a direct line of of the body. So down here, where lead to usually would sit on the patient's body in that access or the generated lead to a point here on line on that line represents the signal that that here picks up. So I've now translated that onto a diagram of the heart in the same plane. Again, you can see the sinoatrial node. The atrioventricular node on the bundle branch is on the Kinji fibers that we just talked about on. Whenever a signal moves towards the ear, you'll see in the top right corner of the screen. We've got positive the line. The golden line will move towards the plus, and whenever the signal moves away, the line will move away from the ear towards the negative sign. So in a normal conduction, you start with a resting level of electricity in the body or in the heart. And as the signal the polarizes from the atrial sinoatrial node down to the atrioventricular node on down to the apex of the heart, you can see that the signal generally moves towards the ear or towards lead to once it reaches the bottom of the heart. It rapidly depolarizing is now. The left side of the heart has a greater amount of muscle my cardio, um and therefore electrical activity than the right side. So the amount of electricity which passes up. That side is typically more therefore, you get this kind of slightly greater electrical conduction to one side. But the overall amount of that electrical activity is away from the from the ear, okay, away from your lead to listening. And so you get this large negative deflection in the signal that you measure. And then over time, as they report arise, the signal returns to baseline and hopefully you'll see that's basically demonstrate what you'd see in lead to on a normal person's E c. G. So that is what your E. C G lead is picking up. So why does this matter? Well, this time we'll talk about lead. One has an example rather than lead to lead one being on the left hand side of the body, usually the one that's generated from the anterior leads on the left. So in this instance, your lead one. Listening here, rather than going in direct line of the heart, sort of splits the heart in two splits the top half on the bottom half of the heart. So you're atrium ventricles apart. So in this case again, you start with an isoelectric line with a baseline amount of electricity and you get this electrical conduction which moves from the atrioventricular does node down to us S. O. U s. A know down ta atrioventricular node on that is towards the But as your conduction is passed down, the bundle branch is and down your interior, part of the heart. It then moves away from the air. So this is going to give you this big negative deflection. And then later on, you'll see that as the signal moves back up again, it moves back up. Both sides is before and then towards the ear again. And in some of circumstances you'll see that that deflection goes away from the ear before returning to baseline. So you may get a little positive flick up so you can see how in the normal heart that's how you would expect the signal to be measured in lead one. So while I'm rambling on about this, well, it's because I want you to understand, is what what happens in a bundle branch block on why a bundle branch block looks the way it does, because I think once you understand, that is actually quite easy to spot on the branch block and I think you'll be less confused by all these cheap ways of remembering it that you'll have been talked through medical school, things like Williams and Marrows and things like that. There's there's ways of remembering it, which are generally easier than that if you understand what's going on. So in this situation we've knocked out all of the left side of the conduction. The left bundle branch is in this patient, and we're gonna walk through again exactly the same as we've done before with our listening ear or our lead one reaching across the heart Say we start with our usual isoelectric line, the signals depolarizing towards the ear like it did before. In this circumstance, that signal is deflecting away from the ear, and it will do so down the right bundle, which initially will look very similar to a normal conductive pathway. But you will notice that towards the end of that it will take longer because there's less fast contracting Ah, faster conducting electrical tissue and you'll also find that the signal moves much slower back towards the isolate the line that we're listening with our ear, and that's because instead of having that big, strong, left sided, very thick muscle full of electrical fibers. You've got the more thin right side of the heart, which is what you're measuring. And so that's what gives you this notched appearance at the bottom of the V, which sometimes looks like a double you. For William, in cases of remembering like that's that's what gives you the notch. And then you could you could ask, Well, how does the left side then conduct electricity? And it does that by diffusion from the right through the remaining conductive tissue, which is either the my card in itself or or residual fibers on. So you get really slow, wide conduction of the left ventricle, which gives you the bronchi or s back towards your ears, said That is a very simple way off, sort of running through why left bundle looks the way it does. And I hope that if you can't take anything else where you take that away so that in future you can spot a left bundle on any CG. So what's all this matter? Well, I think keep the understanding of rhythm. Years really helps with the ciggies. We've talked about that later on We'll have a quick flip through a few drugs. We have time on this sort of stuff does come up in finals. So it's definitely worth knowing. Right then, let's move on to another case. So which of the following terms of does not describe instability? So I've got 68 year old lady. She came into the emergency department with palpitations. She described a horrible pulsatile headache and she felt generally quite dizzy. Uh, one on one C is she started to black out. She she sort of came to very quickly, but did feel very faint. Um, when I examined her, she was very breathless. Shed crackles across both sides of her basis. Um, at the lungs. She'd had some urgent Bloods, which the nursing team had sent when she initially came in on her troponin came back at 103 on her arms of that for you to read Which of the following terms of does not describe instability? What do you guys think? Keep voting, See where we get so this this case is based on a very, uh, similar to really case. Although some parts is slightly interested for the question which I saw any D few weeks ago. It's not unusual to see somebody coming in with cardiac symptoms who is unstable or unwell, and it's important for you to be able to explain what features of that person make them unstable. Um, so I think the majority of people got the runs here, which is good. So he severe pull started aching. So all of these other features shock my card. Ischemia, heart failure and syncope all represent causes off or described terms of instability. So in this patient shock, it's prescribed by a tachycardia on the hypertension. The Micardis scheme years, evidence by the troponin, which is raised heart failure. Although we don't have a BNP to confirm, it seems like there may be some element of heart failure. She's got some crackles at her basis, possibly consistent with pulmonary edema on she's describing, or I've described that she's had a syncope. So why is this the case? Well, when you're thinking about tachycardia, there's analgesic, um, that usually you'll know and you should work through in your head if know with in front of you if you wish, which is almost infallible and it's very well put together by the research council. Obviously, the first part of all assessment when you see in patients is your 8 80. But in the focus of a tachycardia, the real thing you're asking of yourself when you're performing night is is the patient unstable and they describe in stable by these features which you've correctly identified on? It does matter, because if they are unstable, that changes your algorithm and what you do next. And actually, if they're unstable as long as they've got a pulse, you we're going down one pathway. You don't even need to look at the c G necessarily. Um, so let's move on then. So, this lady I was performed my eat 80 on the nurses have thrust this, uh, PCG in front of me. Could you describe what I with me and this represents? Um, so we do have a 12 lead EKG on the next slide, but I think that's enough for you to answer off. Hopefully, that's the rhythm strip of a 12 lead, E c g. Very good. Good. Say it's quite reassuring to see that people can spot some of these arrhythmias, so we've got 65% of people going for monomorphic, uh HVT, which is the correct answer. This is the 12 lead version off that hcg, which is even more obvious, I think, than the rhythm strip alone. For those people who answered ventricular fibrillation, I can see why you'd be thinking enough. They do share some similar features. They are broad in nature on day. Just look generally a bit bizarre, don't they? The thing that makes this much more likely to be VT than the F is the fact that the R interval or the interval between the peaks of all of these waves, looks to be regular. The general height of the waves looks to be similar, and if you took a snapshot of one bit of this and compared it to another bit of it, they look very similar. Ventricular tachycardia is or monomorphic. PT is an organized state. It's the ventricle beating very fast in a northern eyes way, whereas ventricular fibrillation relation is a sort of confused. Fibrillating is the bag of worms in your ventricle, which doesn't produce these nice regular patterns that you see in here. So let's talk about the CT, what's were on it and why I started with it started with a V T. I think partly because I was expecting people to mix it up with the F, which in some cases a few people did, and partly because it's one of the most likely off these arrhythmias to be unstable, which we're going to talk about today. Um so well, the fundamentals is that you must know about VT. Well, it's an arrhythmia. It originates in your ventricles. It causes rapid, usually unsustainable heart rate. You can't sit with this for very long before you start to decompensate. By that, I mean fluid on the lungs, chest pain, blacking out on DPA, sublet, progressing to V F on. Then you know, essentially ending your life. If you're not resuscitated, it can be described a stable or unstable, so stable VT is Consider if you have a pulse unstable. BT If your pulse less And if that's the case, of course, you're going to go down your airless protocol for life support rather than the tachycardia algorithm. Um, sometimes you hear that term sustained or non sustained. V t. What that means, technically is, is any episode of enteric you a tachycardia that's being recorded as lasting less than 30 seconds and self terminates. So sometimes you have patients on cardiac monitors in the hospital or who have had 24 hour EKG is in the community or loop recorder have demonstrated runs, which essentially just means a section off their heart rhythm, which has ventricular tachycardia in it. If it's less than 36 seconds and it stopped on its own, then that's non sustained V T. That's important because if it's non sustained, that suggests that the arrhythmia is more stable, of course, in somebody who's got up on ongoing arrhythmia. So what causes it? Well, usually it's because of a circuit inside the ventricle, so signal pathway, which is going around in a circle amongst itself. And typically that's because of a bit of a scarred muscle or Scott lining of the heart, Um, or in some occasions it can be because of congenital defects or in extreme drug toxicity is a swell on digital Less or digoxin is one that in extreme cases Kenly TVT. So they're reason why I turned. The answer specifically is Monomorphic VT is because in exams that they do get a little bit picky about it sometimes and it's worth knowing the difference. So Monomorphic VT is bit like this EKG we looked at before. They all look very similar. All of the waves have a kind of equal height, usually a similar with on. But like I say, you could take one section of it and compare it to another section, and they would look fairly similar. The other version of ET you might hear about his polymorphic, VT. So that's a ventricular tachycardia, which is often more likely to be mistaken with the F because the height of the complexes are more variable on. But they're not as equally comparable. Sometimes this term for this very specific type of polymorphic VT. Is called torso depart or toast on the point. Um, I'm not mean spinning around the point in French, which basically means that the EKG looks a so it's kind of turning on its axis. So it goes big and then smaller than big and then small. You don't need to read into the small print of this, but the cause is of polymorphic VT and toss. Odds are different to the causes of Monomorphic, VT. In some circumstances. So if you were investigating someone's arrhythmia on a loop recorder. And you had the bottom one of these that the polymorphic, VT. That might lead you down different further investigations compared to the top one, which is why it matters. But from a simple perspective, it's less important. So what the CD features we've talked about already? They're rapid abroad, They're regular and they're large. Okay, so I said I was going to give you a, uh, sort of a way of putting all this information together. It's try and help you remember it on. As we go through, we're going to fill out this table. Really, All you need to know to identify most tachycardia is and keep your patients safe is to be able to say, Is it broader? Is it narrow and is it regular or irregular? And if you can answer those questions, you Kenbrell it down into a very few number of options that could be going on, and you can usually treat without knowing necessarily. The specific diagnosis is well, so we filled out VT in this one right and show you move on. Um, so let's say you did manage to identify this lady's easy GI most of you got it right. You thought she'd got monomorphic VT? Um, what you going to do for her? So what is the first line management off unstable monomorphic PT. So you've got defibrillation synchronized direct current cardioversion load with amiodarone, identity and stops. Court don't know which is a perfectly legitimate option. Because as a junior doctor, if you were left with this situation, I would not be expected Anyone's deal with this on their own. Andi don't know is safer than going for something that you don't know. I get it wrong. But in for the purposes of my lecture, have a guess and see what you get. Give it another few seconds. A select few more people Answer. All righty. Okay. So most people have got the correct answer, which is synchronized direct current cardioversion Um I think the second most answered was defibrillation. And if I'm being slightly unfair in the sense that synchronized direct current cardioversion is a form of deliberate defibrillation, Aleve every similar. But there's a really, really important key difference, which is why I've highlighted this. So defibrillation usually refers to providing electrical stimulus, cross heart muscle without timing it to any particular part of the patients existing rhythm, So essentially it just means shocking the patient without doing anything in particular. So perhaps that's when you're doing CPR on a patient. You have the pads on you come away from the patient and you shock and then you're back on to the patient. You're not looking at the rhythm strip to see what's happening when you supply that shock. Synchronized direct current cardioversion or D. C. C V Cardioversion is where you are timing your shock very specifically to what's going on on the patient's existing rhythm. That matters because if you apply a shock across someone's heart, who's got VT at the wrong time, there's a chance that rather than put in the rhythm back to normal, you could potentially push them into the F or ventricular fibrillation, which is obviously her worst place to be. So why is it not amiodarone? Well, we'll move on to that in a moment, but in an unstable patient. Amiodarone is second line, and I'm pleased to see not too many people put a dentist. See, we're going to come back to Adenosine later, so this is our this is our algorithm or quickly demonstrate where we are now. So we've just been through this case of this lady. She was unstable. We've given her a shock. Hopefully, that's worked. If it's not, we're going to do that on up to three successive attempts, usually with like sedation led by an anesthetist. So not with someone completely awake, because it's very painful and very distressing. If that is unsuccessful, you move on to loading them with amiodarone on. You certainly wouldn't be on your own, hopefully anywhere near these events. But it's very useful to know what's happening, and you do get quest on them in the context of time. I have not run through a case of a patient who is stable with this, But let's imagine that this lady was stable and she was, well, she didn't have any features of shocks into the Micardis cream or heart failure. She was sat there just with the palpitations in a headache, and she wasn't feeling great. We'd move down this algorithm so we'd say that her curious was brought on, would say her that her cure her rhythm was regular on def. That's the case. Then, rather than proceeding straight to DC cardioversion you start with amiodarone. Um, in that particular scenario, you'll see the bottom of the algorithm they've talked about possible other things that can cause a broad regular tachycardia. Um, and it will come on to that later. But if that's the case, then you don't give them amiodarone. You work through the narrow, complex pathway. Well, right, so let's move on something different now we've sort of brought the T to a conclusion. So looking at this CCG rhythm strip in the bottom right hand of corner of the screen which term most accurately describes the most prominent ECD finding. So this is a Ganic similar case I experienced. It's a 29 year old man. He was in the emergency department and he'd come in with palpitations and dizziness was feeling a bit embarrassing. Been well on. He admitted that he'd been using quite a bit of cocaine recently. Hey was otherwise quite fitting Well, on the nurses sort of thrust CCG next to me and I can tell you is hard. It was quite fasting is about 160. So what term most accurately describes that rhythm strip? Okay, great. Okay, So we've got nearly 60% of people with atrial fibrilation, which is the correct answer on then. Second most on high answer was atrial flutter, followed by super ventricular tachycardia. So there's a couple of points is gonna make about this question with some of the focus on finals, things like that. It's really important to read the question when you're answering questions, which sounds really dumb, but it's really easy to miss points. So this particular question. Ask you what the most accurate term is for describing this. Now we're gonna move on super ventricular tachycardia later. But super ventricular tachycardia is a capsule term, which includes any tachycardia is which are originate above the ventricles. So technically, this is a form of SV tea or supraventricular tachycardia. But it could be described more accurately than that. Um, so I put the 12 lead EKG up just so we can try and speak about whether this is flutter or fibrilation, because I think it's really difficult in some circumstances to be able to describe what makes one different to the other on There are circumstances where you won't be able to necessarily be certain there are features of this SED, which make atrial fibrilation correct answer. So it's an irregularly regular rhythm. So if you were able to draw on your computer screen, you would see that although some of the complexes look like they're in a regular pattern, that actually the distance between the peaks of the R waves is not consistent across the C G. On in the gaps between the R waves, you can see this kind of wandering, messy looking baseline. And if you look at lead V one, you could be convinced that this might be flutter because it does look a little bit sore tooth in that lead. Um, the thing that makes up less likely, even though that that is what it's slightly looks like in that case is you've got this wandering baseline so it doesn't look flat is kind of moving up and down is there. It's on a wave. The distance between the R waves is not consistent. Um, on the it's regularly irregular on also the rate, So I haven't calculated it, but I think this when I looked before was about 120 23. Something like that, and usually atrial flutter will be a very specific rate, which will come on two later. About why? That's the case. Um, see, a dancer was atrial fibrilation. So going back to our algorithm, then. So you've got this patient who is stable? He was Well, he was younger, was fit. You stop the palpitations. Um, Andi, he had a narrow complex, so moving on to the right inside of the algorithm. Irregular. We've described tachycardia, so that plus is down here. Um, on that means that this is probably F, which I think we agree. Um, So what you gonna do for him? Well, we're gonna talk a lot about a half tomorrow if you're gonna come into my teacher tomorrow. Um, but you usually rate control these patients with be two blocker or diltiazem, or in some cases, you you get up for rhythm control. I'm not gonna get into a lot about that today, but we'll talk a little bit about F that for those you can attend tomorrow. So what is a f? It's disordered, atrial extra collectivity. It's not one focus of of an initiated rhythm. It's confused. Electrical mess, basically in your atrium on. Along with that, you get abnormal irregular conduction into your ventricles, which is why you have a sort of irregularly irregular rhythm is incredibly common. It's the most common atrial tachycardia have seen in in medicine, and it's very, very common in those over 70 years old. I think it's been like 15% of people over 80 present with a F or have a If so, while you're ACG features what we've talked about it being irregularly irregular people were coming on absence of peewee Aves. That is true. There aren't technically ever any P waves in any ABCG with a F. But often there will be something called a pseudo P wave, which is and then that looks very much like peewee but isn't one on what you're actually seeing. Where the pseudo P wave is is some of that electrical activity being slightly more organized than it is elsewhere along your e C. G. So, yes, you don't see peewee aves, but sometimes you see things that look like the waves. And there no. So the thing to think about is it regular or not? And if it's irregular, is it regularly irregular? I use it a repeating pattern of abnormal beats, or is it just confused? Massive abnormal beats don't say half on. You have this wandering up and down isoelectric baseline because the total amount of electrical conduction in the evening in that area we will, um it will change over time. And of course, it's narrow. Complex. Um, we're talking about tachycardia is today, but you can get slow f so you can have a F with rates less than 60 now, they have rates after than 40. It doesn't have to be fast. It's just about how well your body is able to conduct those funny waves down the down the bottom of the heart. So sorry. So management, then so includes either controlling the rate so slowing them down or putting them back into a normal rhythm. And usually in both of those cases, you need to talk about how you're going to reduce the risk of stroke, which usually includes anticoagulants. But again, we'll talk a bit about that tomorrow if anyone would like to know more. So we're gonna put that in the bottom left corner on our on our chart here. So that is a narrow, complex, irregular rhythm. All right, so I think here we're just gonna have a sort of a 22nd break If anyone wants to have a breather, Sophia, you Do you want to just ah, shouters back in when you want us to start again? Charles, I'll do that. Yeah. So therefore, more minutes to go. Quick burst into drink, and we'll get started again in a minute. All right, Otherwise, I just talked to you fast. Think you think we can restart? All right. I'm sure we get going. So let's have the next case up for everyone who's available. Eso another arrhythmia you've got here. Surprise. Surprise. So how would you describe this patient with me? So this was a 50 year old nurse. She was any d. She had had a really, really busy day on about two. About the thing was the night before, she had had a long night shift, so she'd gone from a night, had sort of half a day off, and then go on holiday. Had half a a day off and gone into a night. So she's not really Give yourself a break. Um, she was asthmatic and and used, uh, Bentyl inhaler three times in the night. She so accidentally breathe in some deodorant when she was in one of the changing rooms and she just felt lightheaded with the racing course, and it got a bit of chest discomfort. So we went to see her and her EKG was similar to this. So how would you describe this patient arrhythmia. So is that SPT is a f Is it VT, or is it flutter good? Okay, So most people have gone for S V. T, which in this circumstance, I think describes our TCG very well because with the limitations of only having lead to to look up is very difficult to say specifically. What kind of, um, s V t that is I think I've got the 12 lead EKG here and you'll see so even better on that, that actually I don't think there's any where you can see obvious sort of flutter waves. It looks very regular. The curious complexes on narrow on there. Some evidence, if you look in the anterior leads the V one vtv three before even some of the lateral leads to be five and b six of what looks to be like ST Depression as well, which would suggest that this person's heart rate's going so fast that they're my cardio Ms Struggling toxin it itself, and it's starting to show some signs of early scheme years. Well, um, so let's talk about CT. But before we get to that, if you've got this lady in front of you, she's as described here. What is the first line management? So I'll tell you now that she's stable. She doesn't have any of those features of instability. So what's the first line management off SBT in a stable patient? Great. Well, I think this has come out excellently, some free, very pleased by that. So yet most people who have answered are correct. The answer is vagal maneuvers on. And I think, uh, we talked about vagal minute. So you may have heard vagabond. It was come up a lot, but I'll talk about while the other answers on correct in a moment so hopefully we can move on to the next. Here. Onto the next slide, you'll see where the other answers were. Incorrect. So we've moved down algorithm again. We've gone down the narrow side this time have decided it's regular on the first line management off a narrow, complex, regular tachycardia in a stable patient is a vagal maneuver. If that is not successful than adenosine, is the next line management. So that's dance. It was the second line monitoring. That's why that was incorrect. Amiodarone was incorrect because amiodarone and typically is used for either unstable patients or in cases of broad, complex tachycardia is like VT, which is what we talked about initially. I'm not sure yet. So if that is the case and you perform of able maneuver on, the patient goes back into normal Sinus rhythm. It's highly likely that that rhythm that they were in was re entry paroxysmal SPT If that's not successful, then probably what you're looking at his atrial flutter, because flutter is less likely, Teo resort to a normal Sinus rhythm in the context of vagal maneuvers and adenosine. And that brings on, I think, quite nicely to talk about what is SPT um because we've related to a few times throughout the lecture on D. I think it's quite helpful to get your head around. What s V t means so I sort of start talking earlier to expend that s V T is super ventricular tachycardia. It refers to any tachycardia which originates above the level of the ventricles that includes the junction. So the Atrioventricular node, as well as the atria on it, includes all of these things. So it's got your regular tachycardia. So a Sinus tachycardia someone who has been on a run. Technically, they've got on SPT off some sort atrial flutter, which is a very specific type of re entry circuit, which we'll talk about later with our classic flutter sawtooth waves. There's something called inappropriate Sinus tachycardia, which might have heard of which is really interesting on could be quite debilitating of patients. That's that's, Ah, a condition where patients get this inappropriate fast heart rate, which is just a regular Sinus tachycardia. But it can come on for complete Rest said it might be watching TV and just get this really banging heart rate the mix and feel awful. Um, it's that's an interesting the might have seen before. There's these atrioventricular rhythms, so these ones that go through the atria is down into the ventricles and back up to the heart now includes a V N R T, which we're going to talk about. You can have a junctional rhythms originated at the TV node or you can have these irregular atrial rhythm. So that's a F which we talked about before, Um, or eight. Your flutter with the variable block, uh, which I'll talk about in a moment. So let's just focus on these two, because these two are the ones that help you understand the physiology on there, the two that you get Kristen under the to that, if you pick him up on a CD, you can do something about. So what is a VI nodal? Reentrant tachycardia? Because this sounds really posh, doesn't it? But it's really not that complicated that the fundamental thing is that it's a very common cause of palpitations in a normal heart. Structurally normal, no heart wise. So you don't have to have scar tissue, and abnormal circuit and abnormal pathway toe have a navy nodal wrench in tachycardia. Usually it's not life threatening, and people compensate for it really well. So you may have had an episode of it in your life and never know about it. Um, it can occur spontaneously or sometimes on provocation with drugs, so that includes, um, Arthrogenic causes. So salbutamol, which is a beta agonist, which this lady in our case was using overnight help with her asthma attack. Can provoke SPT um Ondimba particular a v nodal rendering tachycardia. But also stimulant drugs, things like cocaine. Um, the symptoms are typical of most tachycardia. Is is palpitations and anxiety. Occasionally, people describe a precinct people, they don't usually collapse and they don't usually lose consciousness. Um, and the C G features all this rapid, narrow, complex regular tachycardia. So much like before, I've put together a little diagram of kind of what's happening. So the signal is conducting down initially through the normal circuit, down the heart of the right upper lobe of the left of the right side of the heart. But when it reaches the A V node, it starts to go in this looping circuit around the A V node, and every time it reaches on area of reconnecting sort of signal that passes down the hall, it stimulates it again. So you get this kind of rapid wheel turning around your a V node, which suddenly starts to set you ventricle going, and your ventricle will keep listening to that as long as it can, on a long as it can keep up with it. um, so that's a V nodal. Be entering tachycardia in one slide. So how does that differ from flutter? Because flutter is the other thing. You might see a lot of flutter rather than going just around the A V node. I'll just move back for purposes of describing this. It goes around the whole atrium, so it's not just looping around. That tiny bit of note is looping around whole atrium, and that is why atrial flutter has a typical heart rate of 150 because most people's Atria take a very specific size and therefore a specific time for that signal to pass around. So in cases where you've got a super ventricular tachycardia with a rate of 1 50 you have to be very suspicious that the signals going away around the atria on that is describing atrial flutter. Um, most patients who have atrial flutter have an anti clockwise pathway. That means that the flutter waves are up right, because the signal moves towards thie. He had the listening ear. The EKG leads, which is why they're all right. Flutter waves, but you can't have an anti clock by circuit where it goes. The opposite you kind of a clot while circuit where it goes the other way around. And then you will get flutter waves that just look the same upside down so quickly running through our fundamental. So it's a type of STD can be stable or unstable. So it should our patient have flutter and have had heart failure. My cardio ski me a shock or syncope, Then we'd still be going down. Are D. C C V cardioversion route. It can have something called variable ventricular conduction, So usually atrial flutter will be a regular Sinus tachycardia. But to make things slightly more complicated occasionally you can have something called a variable block, which means that the signal is conducted down into the ventricles, a different amounts so you might have three beats in your atria for warm beat in the ventricles. Three beats in the atrial, one being the ventricles and then two beats in the atrial for one B in the ventricles before it goes back around again so you can have a sort of 332332 type pattern. Or you could have a three to to sort of pattern, which can look irregular But the thing that's important to know is the difference between two R waves will on the difference between your atrial waves were always look should look similar, which is should help you describe it between a f and a flutter. It can be really dangerous and deteriorate VF, um on do you you don't get as much loss of the also electric bass line is you do in a The thing that some people will do is if you have got an atrial tachycardia and you happen to have given adenosine because he thought it was an S V t. That wasn't flutter where you went down. The algorithm is unlikely to terminate, but it might show for the time that it stops up. Conduction Really obvious sore tooth waves. So then you know what you're dealing with. So it's unlikely to stop it. But occasionally it's diagnostic had a scene in the circumstance, so I'm going to just move on. So I don't want Teo run out of time, But I've put that down here. So are narrow, complex, irregular tachycardia is we can have atrial flutter on atrial flutter could also be a narrow, complex, regular tachycardia as well on That's in the context off having a variable block that we just described before. So case full. Then, um, so we've got this nurse. We're just going back to her again. We've described her as having a super ventricular tachycardia. We're going to give her a We're going to give her a formal vagal maneuver. Which of these is is the a less recommended vagal maneuver? So we've got criticized massage, modified valsalva, patient breath holding or dunking into ice cold water or a nice bath. Pleased to see no one's planning on dunking their patients in iced cold water or ice bats have put that on there for a reason, though they're often stories off. Um, well, I say. Often I've heard stories off men and women training in the Army, where they've gone out running, put themselves into SPT Andi. People have helped reserve revert them back into Sinus rhythm by tricking them in ice cold rivers because the shock of going into the cold stimulates very good maneuver. So it does work, but it's not recommended. So crowded Sinus Massad. Well, why is that wrong? That's recently been suggested that it can be harmful in some patients because there's a risk of I'm massaging the carotid area you could potentially damage. Stable plaque can increase the risk of stroke. In reality, I think the evidence of that's very poor, but it's now considered to be the wrong thing to do. So you shouldn't do that. You should do something, called a modified Marsal vermin Evil, which is not the same, was asking the patient to hold their breath. So I'm not gonna play this video, but I recommend you have a look around on YouTube about this or the videos. This is one from the University of Extra on YouTube. It describes how to perform the valsalva maneuver on is very easy to do. Essentially, you ask a patient to blow and hard and fast for a long as they can into 10 mills. Ringe, which generates a lot of negative pressure when they start to get like they can't blow anymore. You rapidly put their head down on the bed and lift up their legs on. That has a sort of almost 60% conversion rate, which is significantly better on evidence compared to the or the maneuvers. So let's move on to case five aware that we've not got so much time and I don't want to run late. Um, so you're working So this is the next question. So which of the following is the most appropriate first line management? So you're working on a M. You on the nursing team bring you an admission E c G that they're quite worried about. And you look over the patient notes and you find out that this is a 69 year old man is come in initially with a community acquired in your own year, and he's on some antibiotics. You look at his background. And he had a non ST elevation myocardial infarction about 10 years ago when he had warned regulating stent. He's got known bundle branch block following that on disease, otherwise quite fitting. Well, really, the nurses have done some obs on. He looks to be stable, is on a small amount of oxygen for is pneumonia. Andi feels much the same as he did before. He's not really sure what all the forces about, but you feel is pulse and it's regular. It's definitely not normal. So which of the following is most appropriate management so Is that gonna be direct current cardioversion. Are we going to give him a modified valsalva? Are we going to give him some flak and I'd or are we going to give him some adenosine? Where are we going to give him some boss up for long. And if you can't think of the answer, just think about that. The algorithm that we were talking about before on this is a hard question on the others. But we're working. We're working up to it, working up to it. Yeah. Give you another few seconds for those that were on the fence. Okay, right. So this is the C g when it's larger, and we're gonna walk through it together. So let's just look at this is a rhythm on the bottom rhythm strip so you can see that it's irregular on Did looks to be irregularly irregular. Um, and we only know one irregularly irregular rhythm, I think, which generally is atrial fibrilation. Although, you know, the other thing that could be irregularly irregular is an atrial flutter with a variable block. We talked about that before, but I can't see any obvious flutter waves and this patient's heart rate was not 150 so I'm not suspicious of that. The other thing that's very obvious in this gentleman is he's got these big, wide, curious complexes. And I think we talked about this before. We were talking about bundle branch block, but that's a very nice example of a left bundle branch block. So bringing that information together, it would look at the This gentleman's got a F with a left bundle branch block. So if we go back to have our tachycardia algorithm, where does this leave us? So without knowing what it was, we said, Well, it was brought on. We said it was irregular, and so we should be asking for some health, which I think is perfectly acceptable. But let's say that we're going to try and look at what we would potentially deal on our own. Um, and the options are that this could either be a f with bundle branch block, which this PCG is all that. This could be something called Precose. I today F um, practice. I step is a little bit complicated, and it's quite rest. I'm not going to go into that today, but you might see occasionally in a patient with atrial fibrilation because it's so common with a bundle branch block, and in those cases you treat because the it's a f. You go down your narrow, complex side and you look at your regulars and you go, Okay, this is a F, and I'm going to manage. That is a F um, So what I'm trying to say is you long as you know this algorithm well, and you understand how to approach it and have to go through step by step. You don't have to know the diagnosis to be able to keep your patient safe on do the right thing. Um, and it comes up loads and exams, and it's really worth getting your head around. So it was very quickly. Talk a little bit about bundle branch block, since we've mentioned it a few times today, so it's an abnormal conduction. It's usually secondary to something else, so it's either you've had some X scheme year, which is damaged. The bundle her hypertension, dilated cardiomyopathy or aortic stenosis of the most common causes that lead to a bundle branch block. Remember, that new left bundle branch block is considered a stemi or an ST Elevation, am I equivalent until you've proven that it's not new. So any new damage bundle branch block is considered to be very harmful. And actually, there's some literature suggests the new right bundle branch block is also concerning. But any broad, complex looking E c g. If you're not confident in the context of someone with chest pain which isn't isn't old, I would get somebody to look at with you. Um, so what determines this to be bundle branch block while it broad usually have a dominant s wave, which is a partially of saying you've got this big downward deflection, the signals going towards the ear first in V one, which usually looks like a V with a notch in it on you usually have what they describe as a big are wave or a big upward deflection in V six. He may seen some textbooks people describing that as a marrow type picture and m. A story is a William Topic chairs a W N. V. One and a M N V six. I don't and find out as a very helpful way of remembering it, and in fact, the way I tend to remember. Is that right? Her is that left bundle? Branch block isn't a s heart s part and it goes down, up, down. Um well, it usually has a sort of notching looking appearance to it with a V all left bundle branch block should have left axis deviation by definition because that's how access works. You're measuring the electrical conduction down on the on an angle and that's changed because of the conduction and the EKG. We'll just look unusual. If you want some special brownie points whenever you're asked by consultant, if you want to identify in somebody who's got known left bundle branch block, if they have possibly had an M I awesome ischemia, then there are a set of crude criteria called the regard criteria, which can give you evidence to support the thoughts that there might be ongoing ischemia in the context of bundle branch block on on. That might come up later on in and your exams and that kind of thing. But typically that's bit higher level. But I thought it's for in there for those who are a bit keen. So that moved onto right Wonder Branch block, which again is very similar to left in in some ways in the sense that it's a feature of abnormal conduction. But it's different in the sense that it doesn't necessarily mean you've got a harm for pathology can be congenital. It could be completely asymptomatic people who go through the whole life with it, and it makes no difference in real terms to their lives. But if it's new on someone's got chest pain than it is considered nowadays to be more concerning than someone with a normal looking the CG without a new right bundle branch block, so again, do you get someone to look at it with you If you're concerned, Um, you have this broad complex because the signals taking longer to conduct and you usually have a dominant are way from the ones you usually have a big upward deflection in V one under A S wave in P six Onda. The rule is that you always have a normal access in right bundle branch block off put sort of inverted commas around that because there's always going to be one reason that it breaks the rule. But typically the access will look normal in right bundle branch block where is in left? One branch block. It's left axis. So let me move on a little bit. So I think we're coming towards put in all of our bits of information together. So we've now put another cause of a broad, irregular rhythm in the bottom corner starts F with a form of a bundle. Branch block can look like a broad, irregular complex. I've got one last question for you. I think if we just got time, I think it's worth going through. So you're on. See? See you. You've been looking after a lady with long QT syndrome. She's coming to hospital. She's unwell. She's feeling dizzy, and she's being worked up for some investigations, possibly for some ablation or a device to stop her heart. Going into these funny rhythms, the nurses put the leads on and you can see this this rhythm. Um what electrolyte abnormality should be checked urgently. So I think we've got most people answered now, so I'm gonna just keep moving for the sake of time. And yes, you're mostly right. C is correct. So potassium. So why is that the case? Well, all of these electrolytes and these tests are important. So sodium, magnesium, potassium and calcium or electrolytes. TSH is a, uh is viral load hormone start stimulating hormone, which not really an electrolyte but is important. Um so sodium itself being very low, very high is very harmful but doesn't typically lead to arrhythmias before it causes other problems. Magnesium can potentiates arrhythmias and can cause problems. We're usually in the context off the magnesium, affecting the potassium level. Um and, oh, high, very high or very low. Potassium can be very harmful. High for hypokalemia. Um, thyroid disorders can lead to a rhythm ears, but not usually acutely. In this circumstance like this in calcium, high or low again can be harmful. But what should you check? Herget Lee. Well, you could get a blood gas with a potassium on it within a minute to get your sodium again. You'll have that on the blood gushed getting the magnesium and the calcium, but could take you 40 minutes. So you should urgently check the potassium. And it'd sort of briefly brings me on to how you gonna investigate arrhythmias, which hopefully is how you would think about most things going to take your history and in part of that history. You've got to focus on drugs. Think about caffeine. Think about things you've given them. Think about cocaine use. Think about their cardiac history, which hopefully will come out in there. But I think about ischemic heart disease. We talked earlier about scar tissue on the heart and how that can potentially it's, um, of these arrhythmias or cause some of thumb. So anyone who's had previous MRI that should be going around your mind on. Then, when you move on to your 80 examination, Really, what you're thinking is, is this patient stable or unstable on that takes you down your your a less pathway that we've talked about. Then you're gonna come on to look at your E C G on. All you really need to know at that point is, is a broad. Is it narrow? Is it regular or irregular? Wouldn't you've done those things? That's when you move onto these parts later. So you're going to take some blood tests. You get a blood gas to know what your potassium is. Think about your TSH. Do you need to do anything clear for, like, drug levels? Could this be somebody on digoxin? that's have too much, Um, on then. Usually, you move on to think about whether or not the sort of structural function of the heart is abnormal. So do you need to look at whether or not their valves normal? Whether or not they're pumping function is normal. That's identified, usually by cardiac cardiogram. On then last line things which are usually decided. It sort of by a senior level is whether or not there's anything underlying this that you need to look for. So do we need to do an angiogram to look at the perfusion to the heart? Is there any possible longstanding conduction problems? So my final slide, then, So bring in all of this together. When you see these patients, you're going to do your history and all of the good stuff we've talked about hopefully going through your mind. Once you've looked at your patient, you examined them. You've decided if they're stable or unstable, you've looked at their ECD. You decided, if its broad, if it's narrow, if it regularly regular, you can put that into this context of this framework we've been talking about today. That would give you an idea about where you are on what your patients probably got wrong with them or least narrowed it down. You gonna go to your tachycardia algorithm? If the patient is unstable, then you know exactly where to go. If you're patient is stable. Your work through that broad, narrow, regular, irregular protocol on, you're gonna act on the things in there. So by the vagal maneuvers, you're gonna give them adenosine. You're going to give them. I'm the odor own. He gonna give him be two blockers, etcetera on, then later down the line. Once you've stabilized that patient and you've achieved what you what you've set out to do with those guidelines, you're gonna take blood test on formula Echo. So that was a big whipped through thank you all so much for listening. I know we've gone nothing with just a time, which is just good for May on. I hope you found that helpful. There's a lot of information in there. Please do go through the slides read over them again. Get your head around it, go to life in the fast lane. Read the information on their websites. If you if you do anything after this video going to Google Google how to do a modified of ourselves a maneuver because it's really good to be able to do that and know how to do it, and you can do anywhere. So if you're out walking, you see someone collapse. It's not a difficult thing to do. Um, you know, you could do it any day you can do on the Ward's. It's a very easy procedure to do, and it could make a big difference to somebody. Um, so thank you all for listening. That's the end of my slide show. I'm not sure if Sophie a had anything that she'd like to say with the boys. No, just basically, thank you for coming. Everyone. I'm sure we'll see you again tomorrow for a second. Cartilage. A lecture. And don't forget to fill of the feedback forms. Fantastic. You Thanks, guys would appreciate up feedback if you can. It does make a big difference for our training and that kind of thing, and it also helps me improve for next time. So I'll leave them upon the screen for a little while just so that you can. You can get hold of those in the slides if you need to. I'm also opposed to the length in the charts