What does discordant ST depression of > 1 mm in leads V1-V3 score on the Sgarbossa Criteria?

The Sgarbossa Criteria are used to assess patients with suspected acute myocardial infarction (AMI) in the context of left bundle branch block (LBBB) on the ECG. The criteria help determine the likelihood of an AMI when the usual ST-segment elevation patterns are obscured by the presence of LBBB.

Among the criteria, discordant ST-segment changes are particularly significant. Discordant ST depression means that the ST segment moves in the opposite direction to the QRS complex. In the case of leads V1-V3 showing ST depression greater than 1 mm, this finding is indicative of a high likelihood of an AMI and is assigned a score of 3 points on the Sgarbossa Criteria.

This scoring reflects the level of concern for ischemia in patients with LBBB. The presence of significant discordant ST depression in the precordial leads (V1-V3) suggests that there is likely significant myocardial damage occurring, warranting further evaluation and intervention.

The scores on the Sgarbossa Criteria total up to help clinicians assess the risk of AMI in patients with LBBB: 3 points for discordant ST depression in V1-V3, 5 points for congruent ST elevation in lead V1