Understanding Scarbosa Criteria for Acute MI

Oct 1, 2024

Lecture on Scarbosa Criteria for Acute Myocardial Infarction Detection

Purpose of Scarbosa Criteria

  • Used to detect acute Myocardial Infarction (MI)
  • Especially useful in the presence of a left bundle branch block

Normal Left Bundle Branch Block

  • Appropriate Discordance: T-wave deflected in the opposite direction as the QRS complex
    • Example V1: QRS down, T-wave and J point positive
    • Example V6: QRS positive, T-wave negative
  • Importance: Concordant waves in left bundle can indicate acute MI

Scarbosa Criteria for Acute MI

  1. ST Elevation > 1mm Concordant with QRS
    • High sensitivity for acute MI
    • Positive QRS, T wave, and J point elevation are concordant
  2. ST Depression > 1mm Concordant with QRS (V1, V2, V3)
    • Negative QRS with a depression concordant with QRS direction
  3. ST Elevation > 5mm in Discordant Waves
    • Negative QRS with T wave, elevation greater than 5mm

Importance

  • Helps distinguish between a left bundle branch block and acute MI

EKG Examples

  • Example 1:
    • Left bundle in V5, V6, and AVL
    • Concordant waves with positive QRS and J point > 1mm
    • V3 shows discordant waves with > 5mm elevation
  • Example 2:
    • Paced rhythm in V2
    • Discordant waves with a J point/ST depression concordant > 1mm

References

  • EKG tutorials by Dr. Alma Chu
  • Additional online resources for Scarbosa criteria

These notes provide a concise yet comprehensive summary of how Scarbosa criteria are applied in detecting acute MI, particularly in the context of left bundle branch blocks or paced rhythms.