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Left anterior hemiblock

Teaching Series - Tachycardia and Left Anterior Fascicular Block

Sat, 10/15/2016 - 15:48 -- Dawn

This series of three ECGs is from a 60-year-old man who was brought to the Emergency Department after being involved in a motor vehicle accident.  No injuries were found, but the patient was severely intoxicated by alcohol consumption.  He was conscious but agitated. 

ECG NO. 1     15:07:23

Left Anterior Fascicular Block (Hemiblock)

Sun, 09/13/2015 - 22:10 -- Dawn

This ECG provides an example of LEFT ANTERIOR FASCICULAR BLOCK (LAFB).  It is from a 71-year-old woman for whom we have no other history.  She also has first-degree AV block and right bundle branch block.  RBBB and LAFB together are called bifascicular block.  It is not uncommon to see this type of bifascicular block, as the right bundle branch and the  anterior fascicle of the left bundle share a blood supply. 

Right Bundle Branch Block With Left Anterior Fascicular Block

Thu, 02/07/2013 - 23:00 -- Dawn

This is a nice, clear right bundle branch block pattern: wide QRS, supraventricular rhythm (NSR), and rSR' pattern in V1. Wide little s waves in Leads I and V6 are also diagnostic. The left axis deviation indicates a left anterior fascicular block, since there is no other apparent reason for the left axis deviation, such as pathological Q waves or LVH. Left anterior fascicular block is a diagnosis of exclusion, also considering that RBBB and LAFB are often seen together (bifascicular block), since the two fascicles have the same blood supply.

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Jason's Blog: ECG Challenge of the Week for Nov. 4th - 18th.

This is a "Routine" resting 12-lead ECG I performed on a patient several months ago in the Outpatient ECG Lab.

72-year-old white man; asymptomatic; resting comfortably in recumbent position.

This is an exercise in "anomalous" beats.

(1.)  Specifically, what are 3rd, 4th, and 10th beats?

PACs With Left Anterior Fascicular Block Aberrancy

Mon, 10/08/2012 - 19:08 -- Dawn

A good example of aberrantly conducted premature beats (PACs or possibly PJCs) that are conducted with a left anterior fascicular block.  The underlying rhythm is sinus at about 80/min.  The timing of the premature beats is best seen in the Lead II rhythm strip at the bottom, as this ECG machine does not print the 12 leads in an uninterrupted manner.  You will see interruptions each time the leads change.

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Jason's Blog: ECG Challenge of the Week for June 10-17. Why did the ventricular rate abruptly decrease?


From June 10, 2012:   As is the case with all practical blogs, I’m encouraging ECG Guru members to engage in active group participation.  Share your thoughts, observations, impressions, findings, and interpretations.  Feel free to compare notes with one another and pick each other’s brains.

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