Ain't right- or- how to read a grossly abnormal appearing ECG

Dr. Mattu walks us through how to read an abnormal appear ECG and not miss the subtle MI.  He recommends a logical, stepwise approach.  By considering the differential of each abnormality seen you can begin to understand what is happening with the pt's heart.  Finally, apply the filter of your final diagnosis and look for the subtle clues to ischemia.

1) Rate and Rhythm
2) Axis
3) Intervals
4) Enlargement
5) Ischemia

Some differentials worth reviewing noted below.

Copa Cardiogram #54

Leftward Axis

• LBBB​
• Pacer
• WPW
• Inferior MI (from Qs)
• LAFB
• LVH
• HyperK

Left Anterior Fascicular Block

• Axis: LAD
• I&avL: qR (small q, large R wave)
• III: rS (small r, large S waves)

Wide QRS

• BBB
• Pacer
• WPW
• Ventricular ectopy (PVC)
• Metabolic (acidosis, hyperkalemia)
• NaCB
• Non specific intraventricular conduction block (LVH)

Key definition: LAFB + RBBB = Bifascicular block