ECG of the Week - 5th May 2014 - Interpretation

This ECG is from a 70 yr old male who presented complaining of palpitations for the last few hours, I managed to get a bit more information and the patient also complained of chest pain for a similar duration.
Check out the comments from our original post here.

Click to enlarge

Rate:

• Mean ventricular rate ~78 bpm

Rhythm:

• Irregular
• Atrial flutter with variable conduction
• Premature ventricular complexes 
• Complexes #4, 6, 13

Axis:

• Normal 

Intervals:

• QRS - Normal (80-100ms)
• QT - 360ms

Segments:

• ST elevation inferior leads
• Measurement difficult due to flutter waves
• ST depression leads I & V1-6 

What happened ?

In addition to the palpitations the patient also complained of central chest pain of similar duration. He had no significant past medical history, was not known to have atrial flutter and was on no regular medication.
Addition serial  ECG's performed on arrival were similar to the ECG above with the inferior ST changes remaining challenging to quantify due to flutter waves and ectopic beats. No posterior leads were performed.
The cardiology team were involved urgently given acute nature of the presentation. The patient underwent urgent PCI, which showed:

• LMCA: Normal
• LAD: Mild-mod diffuse irregularities
• LCx: 100% occlusion after OM1 --> stented
• RCA: Dominant with 30% proximal stenosis
• LV: Normal

Following the PCI the patient remained in atrial flutter for which he underwent successful DC cardioversion following transoesophageal echo.

References / Further Reading

Life in the Fast Lane

• Inferior STEMI
• Atrial Flutter

Textbook

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