Easy EKG: Interpreting Rhythms

April 28, 2019

okay so I just wanted to create this quick little video with me and my friend Charlie here in the corner I'm just to reiterate that this first video you're watching here is designed to teach you the ropes about the specific rhythms and the second video that I just made I have a link in the info of the video that you're watching is designed to test you on those rhythms so again if you have any issues with either of these videos always revert back to the first video I made that talks about the electrical physiology of the heart if you understand that video you'll be able to understand these rhythms no problem so always let me know if you have a question I enjoy these videos right YouTube will welcome back to another one of my cardiology videos about the heart and this is a second video after my first video that I talked about where we went over the basic electro physiology of the heart and I said I was going to get around to doing some videos where we talked about different rhythms that the heart can display and how those would be interpreted and so that's what we're going to do today I apologize it's taken so long medical school has completely consumed my life but I never nonetheless I guess we are here right now we're ready to go do some rhythms so um before you jump into this video make sure you have watched the other video the link is posted in the info if you watch my other video it'll really help you understand what's going on here I've gotten a lot of positive feedback so give her a shot and let's see what we can do here so as you can see up here this is our normal sinus rhythm so we look we have AP wave which is a normal height and the PR interval is okay and we have our cue our s and then we have a T wave so the key RS is the ventricles depolarizing T wave is the repolarization of the ventricles so everything looks good and this is supposed to look good this is a normal sinus rhythm so it looks kind of weird when you let it scroll by and it's just because of the way the software works so you can see up here we have our heart rate which is 72 beats a minute that's normal and then each one of these little squares here can be used just like if it was on a EKG 12-lead printout that you would see so let us get started we'll go and start with the first pathologic rhythm so first off we're just going to start with something easy so we're going to look at this is a sinus bradycardia so what is a sinus bradycardia well it's just essential in your heart rate is a normal sinus rhythm but it is a rate less than 50 beats per minute this isn't necessarily pathological it can be normal in athletes or people who have just a normal low resting heart rate it's only pathological when it causes symptoms such as lightheadedness passing out things of that nature so you can also have sinus bradycardia caused by intense vagal stimulation so you can do a vagal rub on your carotid sinus to get some vagal stimulation but it's typically non-pathological but you know it is something to watch out for so to contradict this we're going to go and we're gonna look at sinus tachycardia so this is typically it's just it's a fast heart rate it's a normal sinus rhythm it's typically caused by increased sympathetic stimulation so you can have that from pain fever creased oxygen demand hypovolemic hypovolemia so if you're dehydrated if you note up here we have a narrow QRS complex and the rate is typically below 150 beats a minute but greater than 100 let's see here so now we're going to go and we will pick let's give you one of these here this is going to be a funnel so what do you think is going on with this rhythm so if we go up here and we look we see we have these QRS complexes right are they're not very well I guess the main thing you want to do when you're looking EKG strip is you want to look for three things a do you have a lingo back to sinus rhythm we'll come back to this one okay so look for three things a do we have a p-wave followed by a QRS wave in every single instance and that's correct we do in this situation the next thing you want to look at are the P waves and QRS complexes evenly spaced so in this situation it looks like they're spaced so we go one two three four squares so they're about four squares I guess you could say and you go member here count one two three four they're good one two three four that's fine with me you can also use these little squares to calculate the heart rate and so to do that you want to go from a QRS to QRS when you count each square so we're going to go 300 150 175 so this is a little under 75 and we see up here that this is at 72 so the way I did that is you count down from 300 each square is equal to 300 so um what's even that out here there we go 300 150 175 so this is around 75 beats per minute now if this one was moved over here to the left then our heart rate would be 300 150 100 beats a minute if it was moved from here to here it would be 300 150 175 60 so it'd be 60 beats per minute so it's just a quick wave you can look at your EKG rhythm and figure out your heart rate so now let's go back to this other one we had going on here so um do we have P waves that we can see well I don't see any P waves there are no P waves are there QRS waves following P ways well we don't have P waves so the QRS is are kind of random right and if we look here at the baseline or the equilibrium electrical potential there is no baseline it's just all over the place it's squiggly it's jumping everywhere and so that is indicative of the atria just going crazy they're fluttering fibrillated fibrillating this is actually an atrial fibrillation so we're not going to get into atrial flutter in this video but yeah this is a fib it's characterized by crazy little squiggly lines here on your equilateral or your equal potential on electrical line followed by a random QRS complexes it's a pretty straightforward thing people it's can be non pathologic typically people are treated with you put on a blood thinner or in a coagulant the only thing that you can have that can make it pathologic um you don't have your atrial kick which is where your atria contract a four-set blood into the ventricles and the reason why I put them on the anticoagulants because since the atria aren't contracting you have the risk for stagnant blood so you can develop clots so that's not what we want so now let's look at this type of rhythm so we did what we did last time we're going to look okay is the P wave in front of a QRS and all times yes that's correct Q waves evenly spaced well let's see 300 150 175 300 150 175 so they look pretty evenly spaced around 75 beats per minute and that's confirmed with our number up here so now the next thing we're going to look at is are there any irregularities in the rhythm I don't see any irregularities just you know looks like a pretty straightforward rhythm however we go in here we look at our P wave to our wave our PR interval this is elongated okay so this little first bump here is the P wave and then we have our cue our s and then our little T wave okay the distance from this P wave to this R wave is greater than 0.2 seconds okay and I can tell it because each one of these little squares is equal to 0.2 seconds essentially and so you're able to tell that because the distance from the P wave to the R wave is elongated this is a first-degree AV block arm and so what this is is essentially you're having a delay in the electrical conductivity through the AV node so it just takes longer for the atria send their signor for excuse me the SA node to send its signal through the atria into the AV node and then down into the ventricles so there's a delay in that AV node so it's can be pathological but we're not going to get into the treatment stuff in this video so that's what it looks like it can be pretty benign you won't catch it if you don't look for it so be sure to look at that one now we're going to move into this rhythm I'll let it play for a little bit so what do you notice are the QRS waves and P waves are they equal are they equally spaced are they normal do they have any irregularities is there a P wave in front of every QRS wave and so just quickly looking here yeah it looks like there's a P wave in front every QRS wave however there is no QRS complex following this P wave right here this is a T wave and here's a P wave and there is no QRS wave here so that's a problem now when you let this play here you see the theme P waves are kind of randomly firing and sometimes they don't have a QRS and sometimes they do and so if you look here let me let this play here right here here's our P wave and there's a very short distance to this QRS complex here's our second P wave and the distance gets longer here's the third P wave the distance gets even longer and the fourth P wave the distance is super long we get to the fifth P wave and it drops the QRS complex completely because what's happening here is again you're having a delay of electrical conductivity through that AV node and the delay is so long that you're actually hitting the cells when they're in the refractory phase so they're not able to conduct a electrical impulse so you just have an inability of that qrs to even fire so this is a second degree AV block type one okay there's also a type two which is seen here so in a type two the difference is let's up that clear off there we go I'm here in the type 2 we can have multiple P waves that are firing without the QRS complex firing so that's the key characteristic is you have one or more QRS complexes being dropped with the PR intervals and so the thing about the PR interval is in type 2 a V or a second degree type 2 AV block is the PR intervals don't change so you see how they're all evenly spaced PQRS PQRS PQRS though are evenly spaced when we go to a second degree type one they get longer PQRS a short PQRS is long PQRS is even longer okay so this is a type one as second-degree AV block type one and this is a second degree AV block type two okay now we're going to move on to the third type of 80 AV block so this is I think the easiest to diagnose this essentially is where your P waves are not having any influence on QRS complexes whatsoever they're just randomly firing and then you're having random QRS firings um it's pretty explanatory I mean you can see it here there is absolutely no pattern that's being followed it's just completely random so that's all there is for that one almost don't get a couple more here to go through so the next one we're going to look at is called a junctional rhythm and this is where the rhythm does not start in the SA node but it actually starts from the AV node um or the AV Junction and so the pacemaker rate in the AV Junction is anywhere from forty to sixty beats per minute and so when we're looking at a lead to here when you have a lead to junctional rhythm you have inverted or absent P waves because remember my other video um when you're looking at the heart if the heart has the electrical impulse going down and away from the SA node you're going to have a positive spike right and in this video or in this situation if we have the impulse starting in the middle of the heart and going up and going down we're going to have an inverted P wave but we're going to have a normal QRS way because the QRS wave is still conducting the electrical impulse the rates of like the right direction but the P way or the atria which are represented by the P waves are not conducting it correctly they're conducting it backwards so if it's backwards you're going to have an inverted P wave but we don't have P waves in this situation that's normal it just it really depends on your patient in that situation so um yeah this is a junctional rhythm alright now let's go to what this one hmm so this is also a normal sinus rhythm which is noted by pqrst all of them are equally spaced there's no random you know depolarizations in between them except for right over here and so we have a pqrst pqrst and then we just had this random spike with an inverted repolarization so this is telling you I guess what this is called is this is a PVC or premature ventricular contraction these can be pathologic you don't want to have a PVC because these things can turn into v-fib very very quickly if they happen at the right time because you can get a reentry rhythm or reentry phenomenon as people will call it also um so essentially this is just a ectopic or a specific part of the heart that is depolarizing that's not supposed to be polarized and when it depolarizes it sends its signals in all directions which can you know it'll depolarize all the cardiac muscle that's not good just make sure you recognize these this is a big red flag okay we have two more so this is a bad rhythm okay this is awful you never want to see this this is called VTEC the way you characterize would be the way you look at it is if you imagine this was a saw it looks kind of like a saw blade doesn't it like you cut down a tree with nice and evenly spaced little sharp points um you know I wouldn't want to have a blade like this come to my arm and that's the characteristic feature this is v-tach so this will kill you because the heart's beating so fast it does not have time to fill up with blood to pump so it's essentially kind of like you're pumping nothing at all it's just beating way too fast so this can be caused by remember the PVC we just looked at a second ago when you have a PVC that happens on top of a tea wave so the repolarization of the ventricles then you can have this phenomenon occur and this will kill you unless it's corrected so but again we're not going to get to the treatments right now next thing this is also deadly this is v-fib this is just random lines of electrical activity the heart is essentially quivering like a bag of worms there is no coordinated contraction there is no cardiac output and this needs to be cured with either successful defibrillation or other pharmacological treatments which again we won't get into so um those are the main rhythms that you should be friendly excuse me should be familiar with as a bonus rhythm I'll give you this one I want you to tell me whether or not you can get it I want you look at it for a second I'll pause it here for you so what this is is this is normal but this is from electrical pacing of the ventricles so when you have a pacemaker or if you have somebody that is in the emergency room and you can do cardio pacing which is where you're applying an electrical stimulus at a specific rate to sort of stimulate the heart artificial um this is what the rhythm will look like in some situation so this little line right here looks like little miniature QRS this is actually the electrical impulse provided by the machine stimulating the heart de contracts and this is stimulating the heart to contract excuse me and this Ridge here depolarization repolarization this is actually the ventricle that's depolarizing so that's what the QRS complex looks like in a paced rhythm from a lead to it's not always going to look like this but this is a good example of one so if you see a really really sharp demarcation here in a line the human body cannot conduct electricity this fast to have this straight up-and-down of a line if you ever see this think that this is artificially induced by some means so I hope that this video has helped you in some ways if you have any questions feel free to send me a message or leave a comment and if there's any other videos you want me to do please let me know and I will try my best to put those out there for you thanks

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  • Reply Magdalene Phakoe April 28, 2019 at 8:41 am

    Thank you. You are the best!!!

  • Reply Dantrell G April 28, 2019 at 8:41 am

    This video just simplified every rhythm for me.

  • Reply Frank Mauromatis April 28, 2019 at 8:41 am

    Guys an asshole

  • Reply Frank Mauromatis April 28, 2019 at 8:41 am

    Again v tach a fusion beat confirms v tach v fib is cardiac arrest dumbass

  • Reply Frank Mauromatis April 28, 2019 at 8:41 am

    Don’t listen to this guy

  • Reply Frank Mauromatis April 28, 2019 at 8:41 am

    Wrong wrong wrong first degree heart block one large square in ever cycle mobitz p wave no qrs also advanced mobitz 2:1 3:1 4:1 winkebach final p wave does not elicit a qrs complex 3 degree hearblock ectopic foci escapes to make a qrs complex juction 40-60 normal narrow qrs ventricles 20-40 pvc like complexes you do not belong teaching stuff you do not know about

  • Reply Amber Martinez April 28, 2019 at 8:41 am

    I found this very helpful thank you!

  • Reply Pippinm7 April 28, 2019 at 8:41 am


  • Reply Shade Tree Cardiology April 28, 2019 at 8:41 am

    Thanks for being a part of the cardiology community here. It's amazing how much people learn when they turn to youtube. More good sources like this are exactly what is needed.

  • Reply Sherlin G April 28, 2019 at 8:41 am

  • Reply Zeynep Başlılar April 28, 2019 at 8:41 am

    u r a blessing!!…

  • Reply Ydnardi Zond April 28, 2019 at 8:41 am

    SB you mean rate less than 60 not 50 .

  • Reply Joseph Lee Canton April 28, 2019 at 8:41 am


  • Reply Drblack M April 28, 2019 at 8:41 am

    Can you tell me the name of the program?

  • Reply c April 28, 2019 at 8:41 am

    What is the name of the software?

  • Reply Elizabeth Dreams April 28, 2019 at 8:41 am

    Thanks for the video…well explained

  • Reply Luky the savage Zombie killer April 28, 2019 at 8:41 am

    Thank you.

  • Reply Too Blessed April 28, 2019 at 8:41 am

    Thank you. Thank you. THANK YOU! I literally thought I was going to have a nervous breakdown after class tonight. Our teacher went waaaaaay too fast, didn't slow down enough for us to take notes nor did they explain it in a way that made sense. I am literally praising God that I ran across your video! LOL

  • Reply drjeyvanthjeyasingh April 28, 2019 at 8:41 am

    can u please tell me what app u r using to show the ecg waves……

  • Reply Anita Blanco April 28, 2019 at 8:41 am

    Great video!

  • Reply Hiền Nguyễn Thu April 28, 2019 at 8:41 am


  • Reply Yeppy 01 April 28, 2019 at 8:41 am

    What program are you using or are you using a website?

  • Reply Patrick Reckner April 28, 2019 at 8:41 am

    Thanks homie very helpful

  • Reply TourStar Productions April 28, 2019 at 8:41 am

    Wrong, sinus bradycardia is a rate less than 60, not 50. Thats why the screens says 54 (which is above 50) excellent video and program, just need to proofread/prewatch your videos dawg, also your wrong again, the small boxes do NOT correspond with a EKG print off, if you look at it the entire P-QRS-T in inside only 3 small boxes (in sinus rythm), which is soo not accurate, the mistakes are now so frequent I cant watch anymore..

  • Reply Jared Gross April 28, 2019 at 8:41 am

    what web site are you using?

  • Reply multisomebodyelse notme April 28, 2019 at 8:41 am

    am 40 an v fit
    use bike a lot and train a lot

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