ToolsCalculators
Sgarbossa's Criteria for MI in Left Bundle Branch Block
ECG criteria for diagnosing acute MI in the presence of LBBB or paced rhythm.
Sgarbossa's Criteria for MI in Left Bundle Branch Block
Concordant ST elevation ≥1 mm in a lead with a positive QRS
Concordant ST depression ≥1 mm in lead V1, V2, or V3
Discordant ST elevation ≥5 mm in a lead with a negative QRS
Result0 points
Does not meet the diagnostic threshold; does not exclude MI.
When to use
- Evaluating for acute MI on an ECG showing LBBB or ventricular paced rhythm, where standard ST-elevation criteria cannot be applied.
Formula
Concordant ST elevation ≥1mm = 5 points; concordant ST depression ≥1mm in V1-V3 = 3 points; discordant ST elevation ≥5mm = 2 points. Score ≥3 is diagnostic.
Pearls and pitfalls
- A modified rule (excessive discordance as a ratio ≥0.25 rather than an absolute 5mm) improves sensitivity and is commonly used alongside the original criteria.