ECG of the Week – 26th January 2015

These ECG's are from a 70 yr old male who presented to the Emergency Department following an overdose of unknown agent / agents.
The first ECG was performed on arrival the second ECG following intervention.  



Vital signs on arrival: 

  • GCS 8 (V=1 E=2 M=5)
  • BP 103/67
  • Temp 36.4 C (97.5 F)
  • BSL 5.8 mmol/L

ECG 1 On arrival to the Emergency Dept
Click to enlarge

ECG 2 Post Intervention
Click to enlarge

Things to think about.

  • What are the key features on the first ECG ?
  • What investigations would you want ?
  • What interventions occurred ?
  • What are the key features of the second ECG ?


ECG of the Week – 19th January 2015 – Interpretation

This ECG is from a 23 yr old female who presented to the Emergency Department following an episode of palpitations. She is fit & healthy and was asymptomatic when this ECG was performed.
Check out the comments from our original post here.


Click to enlarge

Rate:
  • ~66 bpm
Rhythm:
  • Regular
  • Sinus rhythm
Axis:
  • Normal (~40 deg)
Intervals:
  • PR - Short (100ms)
  • QRS - Prolonged (140ms)
  • QT - 440ms
Segments:

  • Discordant ST-segments changes
    • ST Elevation leads aVR, V1-3
    • ST Depression leads I, II, aVL, aVF, V5-6

Additional:

  • Delta-waves lateral leads
  • Dominant S wave lead V1
    • Type B Pattern
Interpretation:
  • Wolff-Parkinson-White Syndrome
    • Short PR segment
    • QRS Prolongation
    • Delta waves

Accessory Pathway Location

There are a number of algorithms that can be used to estimate the location of the accessory pathway (AP). Many of these algorithms can be found in smartphone apps, I use EP Mobile which contains the following algorithms:
  • Arruda Algorithm
  • Milstein Algorithm
  • Modified Arruda Algorithm
For this particular ECG are the algorithms give the same AP location which is antero-septal.
You can find an overview of each of these algorithms at ECGpedia's WPW page.

What are you going to tell your patient ?

I've put some links here to various patient information resources for WPW, I have not vetted or reviewed all these links but have chosen those from government / institutional sites.


If there are other links you feel should be added please comment and I'll add them.

References / Further Reading

Life in the Fast Lane

ECGpedia.org


Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.

ECG of the Week – 12th January 2015 – Interpretation

This ECG is from a 74 yr old female. I don't have any more clinical information on the case unfortunately.
Check out the comments on our original case here.


Click to enlarge


Rate:

  • Ventricular rate ~136 bpm
  • Atrial rate ~ 270 bpm
Rhythm:
  • Regular atrial & ventricular activity
  • Atrial activity best seen in leads I & V1 
    • Notching in terminal portion of QRS and also in isoelectric segment
Atrial activity highlighted in leads I & V1
Click to enlarge
Axis:
  • LAD
Intervals:
  • QRS - Prolonged (140ms)
  • QT - 310ms
Segments:

  • Appropriate ST segment & T wave discordance
  • Sgarbossa Negative
Additional:
  • Typical LBBB Morphology
Interpretation:
  • Regular Wide Complex Tachycardia
  • Evidence of 2:1 conduction 
    • Likely atrial tachycardia or atrial flutter
  • LBBB Morphology
    • DDx - Native, rate related or aberrancy
What would we want to ask our patient ?

The first thing to establish is whether we have time to take a full and detailed history. Clinical instability, e.g. hypotension, mandate urgent resuscitation and rhythm control.
But if we time for a 'chat' there are a number of things to establish in this patient including:
  • Are they symptomatic ?
    • Do they have palpitations ?
    • Do they have - chest pain, dysponea, syncope or pre-syncope ?
  • Do we have a cause ?
    • Concurrent or recent illness ?
    • Has this happened before ?
    • Do they have a chronic dysrhythmia ?
    • Do they have a cardiac history ?
  • What are we going to do about it ?
    • Do we have an accurate onset time ?
    • Are they on long term anti-coagulation - warfarin, NOAC etc ?
    • What do they want us to do ?
  • Do we anticipate sedation / DCCV difficulties ?
    • Previous episodes and outcome
    • Previous sedation or GA
    • Fasting status
  • What is the long term plan ?
    • Consider co-morbidities ?
    • Social circumstance ?
    • Patient / NOK wishes ?
Management Options

Without knowing more about our patient it's difficult to establish the best management but broad consideration are:

  • Rate vs Rhythm Control
  • Correction of any underlying / precipitating condition e.g. infection, electrolyte abnormality, ischaemia etc.
  • Anti-coagulation
  • Long-term management / prevention

References / Further Reading

Life in the Fast Lane


Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.

ECG of the Week – 5th January 2015 – Interpretation

This ECG is from a 78 yr old male with known severe dilated cardiomyopathy. He presented complaining of worsening peripheral oedema, anorexia and weakness.
Check out the comments from our original post here.


Click to enlarge
Rate:
  • 72 bpm
Rhythm:
  • Regular
  • A-V Sequential Pacing
  • Nil native cardiac activity
Axis:
  • Extreme Axis Deviation
Intervals:
  • QRS - Prolonged (200-220 ms)
Segments:

  • Appropriate discordance ST segments / T waves
  • Lead V3 not quite isoelectric but there appears to be some concordant ST depression
    • This was non-dynamic with no history of chest pain
    • Need correlation with old and serial ECG's
    • Sgarbossa criteria do not apply to LV / CRT pacing only RV pacing with LBBB morphology

Additional:
  • Ventricular pacing consists of 2 spikes ~40ms apart
    • Likely LV pacing followed by RV pacing
    • Referred to as LV-RV Offset
  • Negative QRS vector leads I, II, III, aVF, V4-6
    • Due to infero-apical lead positioning
  • Wide tall R wave lead V1 & V2
    • Predominant LV capture
  • Notching within QRS complex
    • Likely reflects significant myocardial scarring and injury as does QRS prolongation
Interpretation:

  • Bi-Ventricular Pacemaker / Cardiac Resynchronization Therapy (CRT)

What happened ? 

The patient had worsening uraemia likely secondary to increasing diuretic dosing contributing to his anorexia with general de-conditioning due to chronic illness. He was admitted for medication review with the aim of symptomatic improvement.

More examples 

We've had a couple of other ECG cases with CRT pacing that can be found here:


Further Reading

For more on Cardiac Resynchronization Therapy (CRT) check out the following resources:

References

Life in the Fast Lane

Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.