ECG Guru - Instructor Resources

A gathering place for instructors of ECG and cardiac topics.

       

Subscribe to me on YouTube

PAC

Left Bundle Branch Block With Left Ventricular Hypertrophy

Tue, 09/20/2016 - 23:14 -- Dawn

This 92-year-old patient was diagnosed with left bundle branch block on ECG, and left ventricular hypertrophy on echocardiogram.  The two conditions are very often seen together, in fact, a majority of LBBB patients have LVH.  Since the two conditions can have similar ECG changes, it is difficult from the ECG alone to determine the presence of LVH when LBBB is present.  If the ECG criteria for LVH are present, it can be assumed that LVH is present, even in the presence of LBBB.  For determining LVH by ECG criteria, the Sokolov-Lyon criteria are commonly used (

ECG Basics: Sinus Bradycardia With A Premature Atrial Contraction

Mon, 04/13/2015 - 21:45 -- Dawn

This strip shows an underlying sinus bradycardia with a rate less than 40/min.  There is one "premature" beat, which can be considered to be ectopic, because it interrupts an otherwise regular rhythm.  The interesting thing is that the premature beat is not terribly early - it is about 740 ms from the previous beat.  If all the beats were spaced like this, the heart rate would be about 84/min.  There is probably an element of "escape" here, in that the ectopic beat is able to express itself due to the slow rate.

Left Bundle Branch Block

Thu, 08/07/2014 - 21:57 -- Dawn

This is a good example of sinus rhythm with left bundle branch block.  There is some irregularity due to a PAC at the beginning.  The QRS is wide at 144 ms (.14 seconds).  There is also first-degree AV block, with a prolonged PR interval of 228 ms.  The criteria for diagnosis of left BBB are:  wide QRS, supraventricular rhythm, and a negatively-deflected QRS in V1 with a positive QRS in Leads I and V6.  

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.

All our content is FREE & COPYRIGHT FREE for non-commercial use

Please be courteous and leave any watermark or author attribution on content you reproduce.

Subscribe to RSS - PAC