Always remember…1, 2, 3, get an old EKG!!!

Step 1: Identify the Rate and Rhythm

  • Is it sinus rhythm?
    • P wave before every QRS
  • Is it one of the tachycardias? (Refer to THIS episode)
  • Is it one of the bradycardias? (Refer to THIS episode)

Step 2: Look for Signs of Ischemia

  • Most consistent way is to examine by anatomic region of the heart
    • II, III, and aVF are “inferior” leads
    • I, aVL, V5, V6 are “lateral” leads
    • V1 and V2 are “septal” leads
    • V3 and V4 are “anterior” leads
  • Check for Q waves
  • Check for ST segment elevation or depression
    • Compare the J point with baseline (TP segment)
  • Check for peaked T waves and T wave inversions
    • T wave inversions in V1 and aVR are normal

Step 3: Look at Intervals

  • PR interval
    • Wolf-Parkinson White Syndrome
    • 1st degree heart block
  • QRS interval
    • Left bundle branch block
    • Right bundle branch block
    • Sodium channel blockade
  • QT interval
    • Long QT syndrome
    • Hypokalemia
    • Risk of torsades de pointes

Step 4: Get an Old EKG

  • If you find anything abnormal looking, compare to an old EKG

Bonus: Scarbossa Criteria

  • Identifies ischemia in patients with a left bundle branch block
    • 1 lead with concordant ST elevation
    • 1 lead with concordant ST depression (V1-V3)
    • Severely discordant ST elevation (>25% preceding S wave)

Additional Reading