ECG of the Week – 8th February 2016

The following ECG is from a 56 yr old female who presented with 3 hours of typical cardiac chest pain. The pain onset coincided with an episode of emotional distress.





Click to enlarge


Things to think about

  • What are the key ECG findings ?
  • What are your differentials for these features ?
  • How would you manage the patient ?

ECG of the Week – 1st February 2016 – Interpretation

The following ECG is from a 60yr old male who had an out-of-hospital cardiac arrest. Return of spontaneous circulation was attained pre-hospital.




Click to enlarge




Rate:

  • 120 bpm

Rhythm:

  • Regularly irregular
  • Bigeminy 
    • Alternating sinus complex and PVC

Axis:

  • Sinus complex – normal axis
  • PVC – extreme axis

Intervals- Sinus Complex:

  • PR – Normal (~200ms)
  • QRS – Normal (100ms)
  • QT – 480ms


Intervals- PVC’s:

  • QRS – Prolonged (120ms)

Segments – Sinus complexes:

  • ST Elevation leads V2 (2mm) V3 (3mm) V4 (2mm) V5 (2mm) V6 (1mm)

Additional:

  • T inversion lead aVL
  • Hyperacute T waves leads V2-4
  • Excessive discordant ST elevation in the PVC’s leads V2-6 – see edited ECG’sbelow

Interpretation:

  • Antero-lateral STEMI
  • Bigeminy

What happened ?

The patient was taken for urgent angiography and PCI and has a mid-LAD lesion stented.

Whilst the key features on this ECG and reasonably apparent the presence of frequent PVC can distract the eye and male interpretation difficult. I’ve edits the ECG below to show only the sinus complexes.

ECG with only sinus complexes shown

The ECG below is edited to only show the PVC’s as they exhibit excessive discordant ST elevation due to concurrent infarction.


ECG with only PVC’s shown

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 – 25th January 2015 – Interpretation

This week’s ECG is another ECG from our patient from last week and the week prior to that. He is an 88yr old male who had an episode of VT on a background of ischaemic cardiomyopathy. Following successful cardioversion he underwent an ICD insertion. He then presented to the Emergency Department complaining of palpitations.



Click to enlarge



Rate:

  • 168

Rhythm:

  • Regular

Axis:

  • LAD

Intervals:

  • QRS – Prolonged (140ms)

Segments:

  • Concordant ST depression in leads V3-6
  • Limb leads show expected discordance

Additional:

  • Regular atrial activity best seen in leads V3-5 in 1:1 ratio with QRS without AV dissociation
  • No precordial concordance
  • RBBB Morphology Rsr’ in lead V2
  • Absence of pacing spikes

Interpretation – Broad differentials include:

  • SVT with aberrancy / pre-existing conduction abnormality
    • Clearly different morphology from prior VT seen here
    • Lack of AV dissociation / Concordance
  • VT
    • Prior episode of VT and known cardiomyopathy
    • Not favored due to lack of ICD shock delivery and morphology features noted above – possibility of ICD malfunction should be considered
  • Pacemaker mediated tachycardia
    • Nil evidence of pacing spikes
    • Morphology clearly different when compared with prior v-paced ECG here


What happened ?

The treating clinicians were concerned about the possibility of ICD malfunction and treated the ECG as VT and performed a successful DC cardioversion.

So why didn’t the ICD shock the patient ? There are only two simple possibilities:

  • Something is wrong with ICD
  • It’s not VT

In this case the ICD didn’t fire because this wasn’t VT. On pacemaker interrogation this was an episode of atrial tachycardia with aberrant conduction and a further episode whilst an in-patient was terminated with iv sotalol.

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 – 25th January 2015

This week’s ECG is another ECG from our patient from last week and the week prior to that. He is an 88yr old male who had an episode of VT on a background of ischaemic cardiomyopathy. Following successful cardioversion he underwent an ICD insertion. He then presented to the Emergency Department complaining of palpitations.



Click to enlarge



Things to think about

  • What are the key ECG features ?
  • What are the differentials for these findings ?

ECG of the Week – 18th January 2015 – Interpretation

This week’s ECG is another ECG from our patient from last week. He is an 88yr old male who had an episode of VT on a background of ischaemic cardiomyopathy. Following successful cardioversion he underwent an ICD insertion. His CXR and ECG are shown below.




Click to enlarge

Rate:

  • 60

Rhythm:

  • Regular
  • Retrograde P waves visible in mid-portion of ST segment
    • Inverted P leads II, III, aVF

Axis:

  • RAD

Intervals:

  • QRS – Prolonged (130ms)
  • QT – 420ms

Segments:

  • Discordant ST segment changes

Additional:

  • Prominent T waves especially leads V2-4 in comparison to QRS magnitude
  • Notching in S wave leads V1-2

Interpretation:

  • V-Paced Rhythm
  • Retrograde P waves
  • Prominent T waves should raise possibility of hyperkalaemia or acute ischaemia but in this case represent patient’s ‘normal’ paced ECG – likely secondary to associated scarring from ischaemic cardiomyopathy
Click to enlarge
What about the CXR ?

I don’t normally cover x-rays on this blog but this one has a few interesting points relating to implantable devices. There is a disconnected old RV pacing lead which ends in overlying the right hemithorax- labelled in green below. There is a new left ICD over the left mid chest with the lead also implanted in the right ventricle. The distal portion of the new lead is the shock coil. This ICD also has an atrial sensing function, the sensors are the two dense square blocks situated in the right atrium.


Click to enlarge


This patient has a Biotronik Lumax ICD which has the ability to provide atrial sensing via a single lead. This allows differentiation between SVT, AF and VT without having to implant an atrial lead. The advantage of a single lead insertion is that it is a quicker procedure and is associated with less complications.

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.