Fantastic video as always, although just a quick doubt: some medicine textbooks indicate that SVT actually encompasses afib, flutter, PSVT & WPW. Is this actually inaccurate, or has the classification changed over time? What classification would you recommend following these days?
That's a great question! I usually spend a few minutes talking about this specific point when I teach this topic in person, but I guess I inadvertently left it out here! The term "SVT,"is actually a bit problematic. Semantically, it would seem to include all tachyarrhythmias other than VT (including sinus tach), but no one uses it in this way. Most PMDs, most subspecialists, most nurses, and some hospitalists use "SVT" to encompass a-fib, a-flutter, atrial tach, AVNRT, and AVRT (among other rarer rhythms). On the other hand, almost all cardiologists, most critical care docs, and most anesthesiologists use "SVT" to encompass a-tach, AVNRT, and AVRT (i.e. leaving out fib and flutter). The reason they do this is that this latter group of rhythms act decidedly differently than fib and flutter, don't require anticoagualation, are relatively difficult to discern from one another (unlike fib and flutter), and usually warrant cardiology referral if recurrent. In other words, the clinical and practical similarities between a-tach, AVRNT, and AVRT are much greater than between those rhythms and fib/flutter. My personal recommendation is to use the term "SVT" as cardiologists do (and how I use it in the video), but to understand that other clinicians may use the term more broadly, which isn't necessarily wrong.
@@StrongMed also once more for good measure-thank you so much for taking the time out of your busy schedule to make videos like these! I'm a student currently rotating through medicine and these videos have been nothing short of a blessing for my friends and me. 🙏
Hello Doctor I would just like to thank you very much for all your impeccable work and exceptional teaching method! I read an ECG book cover to cover, paid for 2 differente courses on the subject and it was your series of videos that had me mastering the subject - by the end of it I was the one my colleagues turned to for questions. Yesterday I had a practical exam and, as part of it, my teacher showed me an ECG. Instantly I could tell it was Atrial Flutter with 2:1 block just by glancing at it, earning me the teachers admiration - and a solid 18 out of 20 in the exam. The feeling of mastering something you once thought was impossible to learn is a very empowerin one indeed. So doctor, once again, thank you. Even though we never met, you are responsible for this success. Thank you, from the bottom of my heart.
Thank you for the update Des!!! You're loved and cherished by everyone! Take it easy and if you want to continue to post or not, it's totally understandable. Sending you much love. 💘 💘 💘
You are so gifted! Thank you so much for your kind lectures! Hope all teachers had your knowledge and the ability to make med students understand these difficult concepts!
That´s by far the best tutorial I have found so far! Thank You very much. :) And now let´s all repeat "regularlyirregular-irregularlyirregular" hundred times :D
mitotianiMartin Good luck with that! A nice thing about recording these videos instead of presenting them in person is that I can go back and record a section again if I can't get the words out.
Thank you Dr Eric Strong. I found you because i search for EKG teaching. I watched this series and went on to watch others. You are a good teacher and very kind to provide knowledge to Doctors,students around the wolrd. Otherwise this will be only for Stanford residents . This is my third watch of this one. . So You are busy with Covid-19 ,arnt you? or it turned out to be seasonal rain, not hurricane ,i heard from Stanford Grand round.
"Occasionally a student or resident can look like a superstar by suggesting flutter from only looking at a rate-as-a-function-of-time graph before having the opportunity of looking at an actual rhythm recording." ... Do you... want us to be superstars? I think I'm gonna cry that is the nicest thing anyone's ever said to me. :D
At 19:30, you point out the P waves are after the QRS (SVT). I am guessing that is a T wave following the P waves. How do I distinguish between the two? Had I looked at this without your description, I would have seen what I thought was inverted T waves and early, but prominent P waves.
This is exactly what I was thinking at this point as well and I'm sure I wouldn't know how to differentiate them either. I'd love to have an explanation for this
HI Dr. Eric, in atrial flutter with variable conduction i dont think its irregularly irregular, because all R-R intervals are a multiplication of "x" (2x,3x,4), they are constant reflecting the circle motion of AF
+Moises Lima You're absolutely correct that the RR interval in a-flutter is usually an integral multiple of x, where x is usually ~200ms. However, when we talk about the "regularity" of the rhythm, we categorize it based on the consistency of the RR interval. If the RR interval is always the same, it's "regular". If it varies according to a predictable pattern, it's "regularly irregular". And if it varies according to an unpredictable pattern, it's "irregularly irregular". In some cases of a-flutter with variable block, we may know that the next RR interval will be a multiple of x, but we don't know what multiple it will be until it happens, and therefore, it's classified as "irregularly irregular". There are other instances of a-flutter with variable block with a consistently repeating pattern (usually 4:1 block alternating with 2:1 block - as seen around 12:20),, in which case it would be referred to as a "regularly irregular" tachycardia.
Megh o Roddur, thanks for the feedback, and thanks for watching! I'd love to do a series on echo. Unfortunately, a major obstacle is that echocardiography falls much further away from my usual scope of clinical practice than EKGs (and other topics already posted), and thus, I would lack sufficient authority to make a high quality and trustworthy series at this time. Also, the barriers to recording, transferring, and displaying patient echos on RU-vid (e.g. software compatibility, privacy issues, and actual ownership of the echos) are much greater than with EKGs. I hope to post videos on echos someday (after I've had time to learn more myself), but sadly, it won't be in the near future.
P. Aliyev Phramacology is definitely on my list of topics to cover. Unfortunately, the list of requests from viewers has grown long, so I can't make any guarantees of when it will get posted, but I promise it will at some point. Thanks for watching!
Hello Dr. Strong, your videos are fantastic. I`ve been through all Intro to EKGs videos. I can`t find the Advanced EKGs videos, are they on youtube. Can you provide a link please. Can`t wait to master the EKG. Thanks
Thanks for your interest! Unfortunately, the advanced EKG videos aren't up yet because I haven't created them yet! (I post videos as I create them.) I will likely be posting one advanced EKG video every 1-2 weeks over the summer and into the fall until they are completed, interspersed with other topics.
U missed Ventricular Fibrillation.. Also I have a basic question. How to differentiate (in ECG) between Sinus tachy and Atrial tachy ? Is the P wave in atrial tachy abnormal unlike in sinus tachy where the P wave should be of normal morphology ?
>Is the P wave in atrial tachy abnormal unlike in sinus tachy where the P wave should be of normal morphology ? Yes. Also, even if the P wave during the arrhythmia looks normal in morphology and axis (i.e. upright in II, downgoing in aVR), you should also make sure that it looks identical to the P wave of the patient when at a normal rate (if a recent baseline ECG is available). Atrial tach can occur from a ectopic focus very close to the sinus node, leading to an ECG which looks like sinus tach when examined in isolation, but only becomes noticeable as something more abnormal when the comparison is made.
Can you send me the links to the videos where you go over AVRT vs. AVNRT as well as ventricular tachycardia versus supraventricular tachycardia with aberancy? Thanks!
Eric's Medical Lectures Hi Dr.Eric, is there a mistake in 11:50 regarding the regularly irregular subtype of atrial flutter? Isn't it 3:1, 2:1 instead of a 4:1, 2:1 AV block? Please enlighten me, thank you very much in advance!
Kal. Jr It's not so much a mistake as it is suboptimal terminology/convention. There are 6 flutter waves for every 2 QRS complexes (some are less visible than others as they are occurring simultaneously with QRS complexes). It's typically described as 2:1 alternating with 4:1, though in reality, it is more like 2.5:1 alternating with 3.5:1. The reason for the inconsistent flutter wave to QRS relationship is probably because of a Wenckebach type phenomenon occurring in the AV node. Although it would seem that this pattern is super specific and very rare, in reality, it's not all that uncommon, and may be the most common form of "a-flutter with variable block".
I can't remember in which of the ECG series I discuss this, but it is a matter of semantics. Logically, it would seem that MAT is a "supraventricular tachycardia" because it's originating from above the ventricles. But then again, so does sinus tachycardia and no one ever refers to sinus tach as such. When most cardiologists, and electrophysiologists in particular, refer to "supraventricular tachycardia" they are using it as an umbrella term for regular, narrow complex rhythms that are frequently mistaken for one another. This includes most notably atrial tach, AVNRT, and orthodromic AVRT, but a few other rarer rhythms as well (e.g. sinus node reentrant tachycardia). MAT is very distinctive and usually not mistaken for something else, as long as one is familiar with it and takes a close look at the full 12 lead ECG. In short, the term SVT would seem to imply inclusion of MAT, but few cardiologists do so.
