Sgarbossa Criteria
  • Left Bundle Branch Blocks (LBBB) are uniquely challeging at interpreting for ischemic changes.
  • ST changes are frequently seen in with LBBB that may or may not be related to ischemia.
  • LBBB are always considered pathological but are not always associated with a myocardial infarction. Decisions regarding thrombolysis and cath lab activation can be difficult.
  • Sgarbossa criteria first described by Elena Sgarbossa offers another tool for assessing for ischemic changes in the context of a LBBB or ventricular paced rhythm.


  • Concordant ST-Elevation of 1 or more mm = 5 points
  • Concordant ST-depression of 1 or more mm in V1-V3 = 3 points
  • Discordant ST-elevation of more that 5 mm = 2 points

Score of 3 or more has a 90% specificity for myocardial infarction. Not sensitive.

Example 1

  • Typical LBBB
  • Concordant ST elevation in the aVF
  • Patient ended having an 100% occluded RCA

Example 2

  • Baseline EKG
  • Shows atrial-sensed and ventricular paced rhythm
  • Same patient but now presenting with chest pain
  • Note concordant ST elevation in the inferior leads(III, aVF).


Sgarbossa E.B. et al. Electrocardiographic diagnosis of evolving acute myocardial infarction in the presence of left bundle-branch block. GUSTO-1. N Engl J Med Feb 1996.