ECG of the Week: ECG of the Week - 13th January 2014

Wednesday 15 January 2014

ECG of the Week - 13th January 2014 - Interpretation

This week's ECG is from a 72yr old with known atrial fibrillation and a PPM in situ. He presents with several days of atypical chest pain. Medications include metoprolol, frusemide, and low molecular weight heparin (intolerant of warfarin).
Check out the comments on the original post here.

Click to enlarge

Rate:

Mean ventricular rate ~78 bpm

Rhythm:

Irregularly irregular native ventricular activity
Nil clear p waves

Irregularity to baseline in leads II, III, V1-2

Single ventricular paced complex

Complex #6

Axis:

Normal

Intervals Native Complexes:

QRS - Normal (~70ms)
QT - 380ms

Intervals Paced Complex:

QRS - Prolonged (120ms)
QT - 420ms

Segments:

ST Elevation aVR
ST Depression leads I, II, V4-6
Discordant ST segment change in paced complex

Additional:

Paced complex occurs 1000ms following R wave peak of preceding complex
T wave inversion leads II, III, aVF, aVL, V4-5
Undulating baseline in inferior and precordial leads

? flutter vs U waves vs artifact

Interpretation:

Rate controlled atrial fibrillation
Single paced complex
ST / T wave changes non-diagnostic, consider

Ischaemia
Drug effects esp. digoxin
Electrolyte abnormality
Doesn't quite meet voltage criteria for LVH

What happened ?

Serial ECG's showed no dynamic changes, and serial troponins were negative.
Medication review confirmed the patient was not on digoxin.
He was discharged from the Emergency Department with planned out-patient cardiology follow-up with his usual specialist.

Sorry for the anti-climactic ending but the truth is that this is what happens to a significant portion of the patients we see with chest pain, non-dynamic longstanding ECG abnormalities, and negative cardiac biomarkers.

References / Further Reading

Life in the Fast Lane