ECG of the Week – 11th July 2016 – Interpretation

The following ECG is from a 38 yr old male who presented complaining of chest pain. Current smoker but nil medical or family history.




Click to enlarge
Rate:
  • 66
Rhythm:
  • Regular
  • Sinus Rhythm
Axis:
  • Normal (-33 deg)
Intervals:
  • PR - Normal (~160ms)
  • QRS - Normal (100ms)
  • QT - 380ms (QTc Bazette 380-400 ms)
Segments:

  • Subtle ST depression leads V4-6

Additional:

  • Deep T wave inversion lead III
  • Biphasic T wave lead aVF
  • Prominent T waves leads I, aVL (of equal or greater height than QRS)

Interpretation:

  • Very suspicous ECG for ACS


What happened ?

The patient had serial ECG's which showed dynamic T wave changes in the inferior leads and T wave amplitude antero-laterally. Serial troponins were positive.
The patient underwent angiography which showed:
  • LMCA: Minor irregularities
  • LAD: Mid 99% single discrete lesion
  • Ostial 1st Diagonal: 90% single discrete lesion
  • CX: Irregularities
  • RCA: Irregularities
A stent was inserted to the LAD lesion and the ostial lesion was treated with balloon angioplasty. Echo showed normal systolic and valvular function.
The patient was commenced on dual anti-platelet therapy (DAPT), statin, ACE and beta-blocker therapy.

References / Further Reading

Life in the Fast Lane

  • Topic 
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 – 4th July 2016 – Interpretation

The following ECG is from a 75 yr old patient who presented with a rash and fever. They had recently been commenced on lenalidomide for multiple myeloma. They are also on warfarin for a prior mitral valve replacement.


Click to enlarge
 

Rate:

  • 48 bpm mean ventricular rate
Rhythm:
  • Irregular
  • Nil p waves visible 
Axis:
  • Right axis deviation
Intervals:
  • QRS - Normal (100ms)
  • QT - 480ms
Segments:
  • ST Depression leads II, III, aVF, V2, V3
 Additional:
  • Biphasic T wave inversion leads II, III, aVF
  • T wave inversion leads V2/3
  • Prominent R waves in all precordial leads
    • R/S >/=1 leads V1-3,V5-6
Interpretation:
  • Broad differentials:
    • Ischaemia
    • Drug toxicity esp digoxin
    • RVH
 
What happened ?
 
 The patient was transferred to CCU for ongoing investigation and management.The patient remained in 'slow' AF with limited exercise rate response and a single chamber PPM was inserted. The rash was felt to be secondary to chemotherapy and resolved with cessation of lenalidomide. 

Chemotherapy related cardiotoxicity

The following are two nice review articles looking at the various manifestations of cardiotoxicity as they related to chemotherapeutic drug use.

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 – 27th June 2016 – Interpretation

The following ECG is from an elderly female who presented with malaise, weight loss and chest pain.


Click to enlarge

Rate:
  • 72 bpm
Rhythm:
  • Regular
Axis:
  • Right axis deviation
Intervals:
  • QRS - Prolonged (120ms)
  • QT - Measured in lead aVL 440ms
  • QT - Measured in leads V4-5 620-640ms
Segments:
  • ST Elevation leads aVR, aVL, V1-3
  • ST Depression leads II, III, aVF, V4-6
Additional:
  • U waves best seen in precordial leads
  • Associated apparent QT prolongation in precordial leads vs limb leads due to T-U fusion
  • T wave inversion leads II, III, aVF, V4-6
  • LVH criteria
    • V4 R >26mm
    • Largest Precordial S + R wave >45mm
    • R wave in aVF ~20mm
Interpretation:

  • Features of hypokalaemia
    • Prominent U waves
    • Apparent QT prolongation due to T-U fusion in precordial leads
    • Cause of / or contributing to T wave inversion & ST depression
  • T wave & ST segment changes could be due to LVH
  • Potential for ACS
    • Needs serial ECG's

What happened ?

Patient's potassium was 2.1 mmol/L. Serial troponins were negative. Partial resolution of ST segment depression and resolution of U waves once K was corrected. 

Hypokalemia ECG's on the Web

  • ECG of the Week - We've had some examples of hypokalemia previous check them out here here.
  • Dr Smith's ECG Blog - multiple great examples of hypokalaemic ECGs here.
  • Dr Ken Grauer's ECG Interpretation - A great walk through of ECG changes in hypokalaemia here.
  • Amal Mattu's ECG Video - ECG findings in severe hypokalaemia here.
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 – 4th July 2016

The following ECG is from a 75 yr old patient who presented with a rash and fever. They had recently been commenced on lenalidomide for multiple myeloma. They are also on warfarin for a prior mitral valve replacement.



Click to enlarge
Things to think about

  • What are the key ECG features ?
  • What are the differentials for these features ?
  • What are the potential cardiac side effects from chemotherapy agents ?