ECG of the Week – 6th April 2015 – Interpretation

This week's ECG is from a 32yr old female with a history of palpitations. She takes flecanide and verapamil. She presents to the Emergency Department complaining of palpitations for the last few hours. She is conscious, denies chest pain or dysponea and her blood pressure is normal.
Check out the comments on our original post here.

Click to enlarge
Rate:
  • 132 bpm
Rhythm:
  • Regular
  • Evidence of possible AV dissociation
    • Notching best seen in rhythm strip irregularly occurs at differing portions of QRS ( red circles in abridged rhythm strip below)
Abridged rhythm strip - atrial activity circled

Axis:
  • Right / Inferior (105 deg)
Intervals:
  • QRS - Prolonged (100ms)
Additional:
  • Discordant ST / T-wave changes
  • LBBB morphology
Interpretation:
  • Broad Complex Tachycardia
General DDx include:
  • Ventricular tachycardia
  • SVT with aberrancy
  • SVT with pre-existing block
  • SVT with pre-excitation / WPW
  • Paced rhythm
  • Electrolyte abnormality / toxicological / environmental

 So what does our ECG show ?

The combination of LBBB morphology and right axis deviation is consistent with Right Ventricular Outflow Tract Tachycardia (RVOT). This is a type of monomorphic VT originating from the right outflow tract or tricuspid annulus it is commonly seen in structurally normal hearts and is usually haemodynamically well tolerated. RVOT can be terminated with vagal maneuvers, adenosine and is also sensitive to verapamil. 

Following vagal maneuvers the patient's subsequent ECG is below.

Post vagal maneuver
This ECG shows a combination of sinus rhythm and ventricular ectopics. Note the normal T wave morphology in the precordial leads, inferior axis and lack of epsilon wave in the sinus complexes. The ventricular ectopics share the same LBBB morphology and inferior / right axis seen in the first ECG and are occurring frequently. 

The patient was given iv verapamil and returned to consistent sinus rhythm, long term management will be with plan ablation therapy.

RVOT can also be seen in arrhythmogenic right ventricular dysplasia, you can read more about this condition in the Life in the Fast Lane ECG library (link below).

There is a great and brief overview of idiopathic ventricular tachycardias from the E-Journal of the ESC Council for Cardiology Practice that I would recommend:




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 – 13th April 2015

This ECG is from an 89 yr old male with multiple co-morbidities including cognitive impairment, cardiac failure and diabetes. He presented to the Emergency Department with several hours of chest pain and has a PPM in-situ for an unknown indication.





Things to think about


  • What are the key ECG features ?
  • What are you going to do about them ?

ECG of the Week – 30th March 2015 – Interpretation

This ECG is from an 80 yr old male who presented to the Emergency Department feeling generally unwell for the preceding 10 hours ! He denied chest pain, dysponea or syncope. He had a history of paroxysmal atrial fibrillation and had a single chamber PPM in-situ for bradycardia. Vital signs were within normal limits.
Check out the comments form our original post here.



Click to enlarge
Sorry about the image quality my scanner is broken so I had to take a picture with my phone !

Rate:
  • ~192 bpm
Rhythm:
  • Regular
  • AV Dissociation
    • Notching in upstroke of some QRS complexes and notching in T wave of complex 21
    • Could be Josephson's Sign rather than dissociation
Axis:
  • Right axis deviation
Intervals:
  • QRS - Prolonged (120-140ms)
  • QT - 280-320ms
Additional:

  • Positive precordial concordance
  • All QRS complexes in leads V1-6 are positive
  • Discordant ST segment and T wave changes
  • Nil fusion or capture beats


Interpretation:

  • Broad Complex Tachycardia
  • Multiple features support VT as listed above plus patients age

What happened ?

The patient was successfully DC cardioverted. 
His post-cardioversion ECG is below.

Click to enlarge
Post-cardioversion we can see a regular ventricular paced rhythm with LBBB morphology consistent with RV pacing and expected discordant ST / T wave changes (Sgarbossa negative). Note the absence of native atrial or ventricular activity.

DC Cardioversion when PPM/AICD is present

Australian Resuscitation Guideline 11.4 makes reference to pad/paddle placement in patients with ICD/PPM in situ.

Click to enlarge

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 – 6th April 2015

This week's ECG is from a 32yr old female with a history of palpitations. She takes flecanide and verapamil. She presents to the Emergency Department complaining of palpitations for the last few hours. She is conscious, denies chest pain or dysponea and her blood pressure is normal.




Click to enlarge

Things to think about
  • What are the key ECG features ?
  • What are the potential diagnoses ?
  • What are you going to do about it ?

ECG of the Week – 30th March 2015

This ECG is from an 80 yr old male who presented to the Emergency Department feeling generally unwell for the preceding 10 hours ! He denied chest pain, dysponea or syncope. He had a history of paroxysmal atrial fibrillation and had a single chamber PPM in-situ for bradycardia. Vital signs were within normal limits.




Click to enlarge
Sorry about the image quality my scanner is broken so I had to take a picture with my phone !

Things to think about


  • What are the key ECG features ?
  • What are you going to do about it ?
  • How does the pacemaker affect your plan ?

ECG of the Week – 23rd March 2015 – Interpretation

This ECG is from a 35 yr old male who presented to the Emergency Department following an episode of exertional syncope. He has 1 previous episode of syncope several years prior without investigation. Otherwise he is fit & well with no relevant family history.
Check out the comments on our original post here.



Click to enlarge
Rate:
  • 78 bpm
Rhythm:
  • Regular
  • Sinus rhythm
Axis:
  • Normal
Intervals:
  • PR - Normal (~180ms)
  • QRS - Normal (100ms)
  • QT - 360ms (QTc Bazette 410 ms)
Segments:
  • Concave ST elevation leads V2-4
  • Nil ST depression
Additional:
  • Voltage criteria for LVH
    • R wave V5 + S wave V1 ~35mm
    • R wave aVF >20mm
  • Narrow deep Q waves leads II, III, aVF, V4-6
  • Partial RBBB pattern - rSr' in lead V1
Interpretation:
  • Given the history of exertional syncope plus LVH with infero-lateral deep Q waves the major concern would be hypertrophic cardiomyopathy.

What happened ?

The ECG changes were appreciated and the patient had a cardiology review and urgent echo. His echo was entirely normal and he was discharged with out-patient cardiology follow-up.

For a bit more on echo findings in HCM and new echo modalities check out the following:

  • Williams LK, Frenneaux MP, Steeds RP. Echocardiography in hypertrophic cardiomyopathy diagnosis, prognosis, and role in management. Eur J Echocardiogr. 2009 Dec;10(8):iii9-14 PMID: 19889657 Full text here
  • Afonso LC, Bernal J, Bax JJ, Abraham TP. Echocardiography in Hypertrophic Cardiomyopathy The Role of Conventional and Emerging Technologies. J Am Coll Cardiol Img. 2008;1(6):787-800. Full text here.
  • Losi MA, Nistri S, Galderisi M, Betocchi S, Cecchi F, Olivotto I, Agricola E, Ballo P, Buralli S, D'Andrea A, D'Errico A, Mele D, Sciomer S, Mondillo S; Working Group of Echocardiography of the Italian Society of Cardiology. Echocardiography in patients with hypertrophic cardiomyopathy: usefulness of old and new techniques in the diagnosis and pathophysiological assessment. Cardiovasc Ultrasound. 2010 Mar 17;8:7. Full text here
I was wondering on our readers thoughts on diagnostic criteria for HCM and the reliability /negative predictive value of a normal resting echo in these cases. Do patients need to go on for dynamic testing (stress echo) and/or cardiac MRI ?

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.