Intro to EKG Interpretation - Bundle Branch Blocks

A lecture on intraventricular conduction delays, including bundle branch blocks (complete and incomplete), fascicular blocks, and non-specific intraventricular conduction delay. Major etiologies of these diagnoses are reviewed as well. I highly recommend watching it in full screen mode in 1080p.

[sunny-handa]

3 am and non medical person watching this for no reason. Irony

[KarenCHS]

Hi there, I'm a junior off-service resident on my first internal medicine/cardiology block of the year. I really appreciate the video. The clearest explanation of Bundle Branch Blocks that I've found. Thanks, and I will definitely recommend to my junior colleagues!

[StrongMed]

block has very subtle variations in how it's defined by different sources.  The most commonly cited definition is: trifascicular block = RBBB + (left anterior fascicular block OR left posterior fascicular block) + 1st degree AV block.  However, as per my wife (an electrophysiologist), it's best defined as: trifascicular block = RBBB + (LAFB OR LPFB) + (1st degree AV Block OR type 1 2nd degree AV Block).  Most cardiologists, my wife included, don't like the term trifascicular block since block of all three fascicles (e.g. right bundle branch, left anterior fascicle, and left posterior fascicle) would necessarily result in complete heart block.  In addition, even if one uses the infrequent term "incomplete trifascicular block" to refer to the situation where conduction in the 3rd fascicle isn't completely blocked, but just slowed (i.e. the definitions above) - it's still misleading because the AV block one sees in this situation may actually be located in the AV node, and not in the 3rd fascicle as implied by the term.  In summary, trifascicular block is a term with which clinicians should be familiar, but shouldn't necessarily use themselves.

[StrongMed]

Jason, thanks for the feedback. I thought about a couple different approaches to the organization of that diagram, but maybe didn't choose the best. I'll try a different one the next time one of the EKG lectures calls for it.

[_ShaDynasty]

great video, but your diagram @ 4:05 is a bit confusing, a top down view would be better.

[sibhare]

6:48 "A tall, single R wave in v6"! What's their number? ;)

[bronzee]

Don't understand the dislikes! Thank You Amazing lecture.

[agnieszkasoteljackson]

I don't understand the orientation of the transverse section of the heart and placement of precordial leads. If the placement of the precordial leads indicates the front of the body ("top") then the heart and the leads are on the right side ...? if, on the other hand, the front of the body is on the "bottom", then the precordial leads appear to be placed on the pt's back....?

[knowledgepower]

Amazing content - incredibly informative & educational. PUT MORE QUIZES AT THE END TO HELP the people who watch to understand the knowledge better. The way you set up the Quiz for Chamber Enlargement was phenomenal. Pocket Brain by Ken Grauer is top notch btw.

[Karma_-l]

its been 9 years and we still benefits from this. thank you.

[zaidmousa]

I find it strange that Ventricular Depolarization in V1 would be Negative rather than Positive. Does LV still have a stronger vector than RV during LBBB, just that the whole process is prolonged?

[viciu]

Love all the lectures but this one is little chaotic, that would be great if you circle things we need to look at. Also with Bifascicular Block on the last strip I don't see RBBB anywhere and there is no explanation why it's different from "classic" RBBB

[naderfayek]

If bufasicular block is due to right bundle branch block and left posterior hemiblock, there will be RBBB and right axis deviation is it true ??

[elenakennebury]

Thank you Eric. It's so incredibly visual and clear explained

[maxusadoc]

Hi Thanks for the lecture very helpful.
What I would like to see is to show on the actual ekg what you mean with a red cursor preferably. This would be much clearer than just talking about it!
Thanks again

[aymanradwan]

brilliant it is the best ECG explanation i ever heard Thanks a lot
it would be great if you explained the whole ecg in such way

[kamlight]

hello! trying to come to terms with all blocks this morning. Is there always an axis deviation with fascicular blocks? that is if i first look at axis, then eliminate either a LBBB if there is a left axis, then a partial block could the next step be eliminating a left posterior fascicular block? I'm trying to understand the relationship with axis and fascicular block.

[criticalthinking]

Thank you. Great lecture.
In the post-Soviet countries there are no such videos.

[jelenalenaable]

I thought I will never understand EKG before I watched your videos! Thank you so much! you are much better than any book! Very helpful! <3

[kuvanr]

Extremely useful for medical students. Helping me a lot for my cardiology rotation. I really enjoy these lectures. amazing stuff. Very well explained. it couldnt be clearer.