Second degree AVB LBBB

This ECG shows second-degree AV block, Mobitz Type II and an interventricular conduction delay, probably left bundle branch block. The QRS width is about 130 ms, or .13 seconds. It appears that this ECG was run with the right and left arm electrodes reversed, so we cannot demonstrate the usual criteria of LBBB:  Wide QRS, Supraventricular rhythm, V1 negative deflection and Leads I and V6 with positive deflections.  When the arm electrodes are reversed, Lead I becomes negative, Leads II and III switch places, and Leads aVL and aVR switch places.

Second degree AVB type Mobitz

Here is the ECG of an 80-year-old lady who has collapsed or syncopated several times. The ECG comes from a Holter-ECG. She has arterial hypertension and acoronary heart disease. The ECG shows a second degree type mobitz AV block. In contrast to second degree AV block type I, in type II the PP intervals are usually the same and the PQ intervals before and after the failed QRS complex are necessarily identical. At the moment i can`t upload the files with high resolution.


Here is the EKG of a 54 -year -old woman without known cardiac disease. The EKG was routinely carried out before a surgical intervention. It`s a screenshot. You can see a normal SR with narrow QRS, followed by an incompete LBBB and then a complete LBBB. A LBBB is often associated with cardiac diseases, but it also occurs without a heart disease. At the moment i can`t upload the files with high resolution. You can download (in German: herunterladen) the image with high resolution here:

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Welcome Dr. Andreas Roeschl

Welcome to Dr. Andreas Roeschl, who is a cardiologist and ECG instructor in Germany.  He will have a recurring blog on the Guru, contributing his knowledge about ECG and teaching, along with ECGs from his collection.  His ECGs are digitized and beautiful quality for reproduction, and his contributions will be a great asset to any student or teacher of ECG.  Dr. Ken Grauer and I want you to feel free to ask us and Dr. Roeschl any questions you have about ECG or teaching ECG.  That is the mission of this website - to make it easier for instructors to teach.

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The ECG Guru's Big Wish For 2020

Hi, everyone!  Happy Winter holidays.  We are so happy you are here.  We have one BIG REQUEST that would make the ECG Guru team so happy.    We would love to hear your comments and field your questions!  There is a "Comments" section below each piece of content.

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Do You Teach ECG or Cardiology Classes?

This ECG Guru website exists for the purpose of sharing teaching resources with anyone who teaches ECG or Cardiology classes.  It can be difficult to find non-copyrighted and free images to use in presentations.  Often, those resources that are available are too small to reproduce well for a handout or projector.  Our website seeks to fill this gap to make it easier for more people all over the world to receive ECG education.

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Want Some Tips On Teaching Axis Determination?

Teaching Axis Determination


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Basics of ECG Rhythm Diagnosis Videos From Dr. Ken Grauer, M.D.

Those of you who have followed the ECG Guru for a while are very familiar with the work of Dr. Ken Grauer, M.D.  He is a generous contributer to the ECG Guru website, and functions as our official Consulting Expert.  He has published many books and e-publications which are (in our opinion) some of the BEST ECG references available, and he has worked hard to keep them low priced to make them available to all of us.  He also offers seemingly endless ECG knowledge and insights for FREE, via this website, his own website, and social media.

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Are You New to Laddergrams?

A laddergram is a diagram of conduction through the heart, presented in a minimum of three tiers, one for the atria, one for the AV junction, and one for the ventricles.  Laddergrams are very useful for presenting and testing your theory of a dysrhythmia.  Instructors often use them to illustrate complex dysrhythmia mechanisms.  

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ECG TEACHING VIDEOS - An Important Tool For Teachers and Students Alike

If you are a teacher, watching a masterful teacher present your topic can help you develop your style, and increase your own knowledge of your subject.  We don't all have the opportunity to attend live classes by the real ECG Gurus of the world, but many of them are now making FREE video lectures available to all of us. Even if you are not an instructor, for many of us, hearing and seeing the presentation is a more effective way to learn than just reading.    


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