Download ECGs, Illustrations, and other Resources for your classes.

ALL OUR CONTENT IS FREE OF CHARGE AND FREE OF COPYRIGHT IF USED IN A CLASSROOM SETTING

ECG Challenge from
Limmer Creative & ECG Guru

Great practice strips for your students. Easy to use app for your mobile device

GET THE APP

ECG & ILLUSTRATIONS ARCHIVES SEARCH (SCROLLABLE LIST)

Dawn’s Classes

Are you transferring to a monitored area? About to start EMT, Paramedic, Nursing, or Med school? Having trouble with ECG classes? Dawn Altman 0ffers customized ECG Classes on site or via Zoom. We offer many topics and levels. Individual tutoring via Zoom also available
[email protected]
CONTACT DAWN
Dawn's picture

Instructors' Collection ECG - Inferior Posterior Wall M.I. In Cabrera Format

Does something about this ECG look "different" to you?    This ECG shows a “classic” presentation of inferior-posterior M.I. when it is caused by a lesion in the right coronary artery (RCA). There are ST elevations in leads II, III, and aVF.  Reciprocal ST depression is seen in Leads I and aVL.  There is also reciprocal ST depression in Leads V1 – V3.  These more rightward anterior leads are reciprocal to the posterior (or posterior-lateral) wall, so the ST elevation is actually posterior.  Another sign that this is an RCA lesion is that the ST elevation in Lead III looks worse than the STE in Lead II.  It would be helpful to check the right precordial leads, or at least V4 Right, as elevation there would indicate right ventricular M.I. 

Depending on how experienced you are at evaluating ECGs, you might have immediately noticed something “different” about this tracing.  It is printed in Cabrera format, which groups the leads (viewpoints) more geographically than a traditional ECG does.  In addition to grouping the leads more geographically, instead of aVR, the machine records - aVR.  That reverses the negative and positive poles of aVR, putting the positive ("seeking") electrode at 30 degrees - halfway between Leads I and II.   Those of us who have been looking at ECGs for decades often feel a bit disconcerted by this format, because we have developed almost an intuitive way of seeing the ECG as a “map”, and this rearrangement thwarts our brains’ approach to the ECG.  I would imagine, however, that this might make interpretation a bit easier for someone who is not prejudiced by the standard way of printing.  This method is especially helpful when looking for inferior wall M.I., as we see here, because the lateral leads are together in a row, and the inferior leads are grouped together. 

Dr A Röschl's picture

AVNRT TYPICAL FORM

18-year-old male; palpitations lasting hours, beginning at the age of 10. What arrhythmia is present? Let's first consider the heart rate: with a heart rate of 194 beats/min, the heart rate is too low for atrial flutter (1:1) (except in patients who have been pre-treated with medication), and the rate would be unusually high for atrial flutter with 2:1 conduction. Due to the regularity of the heart rhythm, atrial fibrillation can also be ruled out. This leaves atrial tachycardia, junctional tachycardia, AVNRT, and AVRT as possibilities.

Dr A Röschl's picture

Nonconducted PACs

A common cause of pauses and bradycardia are non-conducted PACs, which generally do not require treatment. Therefore, it is important to differentiate between pauses or bradycardia that require treatment.

Dr A Röschl's picture

Polymorphic ventricular tachycardia during a stress EKG. What is the most likely cause?

This EKG shows a sinus rhythm with ventricular bigeminy and retrograde conduction leading to retrograde depolarization of the sinus node, resulting in a longer pause (sinus node reset).
Then, a polymorphic ventricular tachycardia occurs over 7 beats. The QT interval of the sinus beats does not appear prolonged, thus ruling out Torsades de Pointes tachycardia. The most likely cause of this type of polymorphic ventricular tachycardia during a stress EKG is cardiac ischemia/coronary artery disease.

Dr A Röschl's picture

SICK SINUS SYNDROME

This EKG shows the classic features of sick sinus syndrome. Initially, there is an accelerated atrial rhythm/atrial tachycardia. After a pre-automatic pause of 2609 ms, a ventricular premature beat occurs, followed by a junctional escape rhythm. Pre-automatic pause is a pause after a tachycardia and before an automatic rhythm, like sinus rhythm or, in this case, junctional escape rhythm. Therefore, there is an alternation between tachycardic phases and very bradycardic rhythms, the classic bradycardia/tachycardia syndrome. Paper speed is 12.5 mm/sec.

Dr A Röschl's picture

Impending Trifascicular AV Block

Here we see the EKG of a 63-year-old man with CAD without relevant coronary stenosis. He complains of slightly reduced performance, but no other symptoms. The ECG shows the following changes:

Dr A Röschl's picture

WHY IS THIS VT

The tachycardia starts with a premature broad QRS complex. We see nonconducted sinus P waves. There are more QRS complexes than P waves, so it is AV-dissociation. There is no doubt that there is a VT present here.

Dr A Röschl's picture

SINUS ARRHYTHMIA

Here we see the EKG of a 15-year-old girl. The rhythm is irregular, with the heart rate fluctuating between approximately 60 and 90 beats per minute. All P waves are identical, and the PR interval is always constant. Therefore, a sinus arrhythmia is present. In this case, it is a respiratory sinus arrhythmia, which is commonly found in younger individuals. The heart rate increases reflexively during inspiration and decreases during exspiration. This physiological sinus arrhythmia is usually no longer present in older individuals.

Dr A Röschl's picture

SECOND DEGREE AVB TYPE I (WENCKEBACH)

We see the EKG of an 81-year-old patient with a pacemaker; the PM was briefly deactivated to assess the patient's intrinsic heart rhythm. At the beginning of the EKG, there is already a prolonged AV conduction time, which progressively lengthens from beat to beat. The last conducted P-wave has a PR interval of nearly 800 ms (!). The next P-wave is blocked, but the subsequent displayed P-waves are conducted again, with the PR interval increasing from beat to beat. This indicates a classic second degree AVB Type Mobitz I (Wenckebach).

Dr A Röschl's picture

SSS (SICK SINUS SYNDROME)

Why does this EKG indicate a sick sinus node? First, we observe a sinus rhythm with a rate just below 60 bpm. Then, there is a pause of approximately 3000 ms, followed not by a sinus beat, but by a junctional escape beat (retrograde/inverted P-wave immediately after the QRS complex). This ECG was recorded at the general practitioner's office, and it can be assumed that no vagal stimulus contributed to the arrhythmia.

ECG Guru Ads - Products and Services of Interest to our Members

 If you would like to place ads for products or services of interest to our readers, please contact us at [email protected]

 

1924:  Willem Einthoven wins the Nobel prize for inventing the electrocardiograph.

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.

Become an ECG Guru Member!

By registering as a member, you will be able to comment on our blogs, ECGs, art and other content.

Help Support the ECG Guru

in our efforts to provide high-quality, copyright FREE content for instructors and their students