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No. While the ST segments do appear to be elevated in leads II, III and avF, to technically meet Scarbossa criteria, there must be ST segment elevation of 5 mm or more that is discordant with the QRS complex. Of note, this ECG criteria has the weakest predictive value of all three Sgarbossa criteria.
The other Sgarbossa criteria - which have greater predictive values for detecting acute MI in the presence of LBBB - are:
- ST segment elevation of 1 mm or more that is in the same direction as the QRS complex in any lead
- ST segment depression of 1 mm or more in any lead from V1 to V3
Source
Goldberger, A. "Electrocardiographic diagnosis of myocardial infarction in the presence of bundle branch block or paced rhythm" Up to Date. May 2011.
If you switch to >20% of the S-depth (Smith's modification) or use Sylvester's modification (another proportional test), it becomes a more predictive finding.
ReplyDeleteAgreed. Excessive discordance is present in leads III and aVF (ST/QRS ration > 0.2). This is a STEMI equivalent.
ReplyDeleteIn addition to Christopher's comment, i would add that "Smith's modification" is also valid to measure excessively discordant depression.
ReplyDeleteI believe that aVL is the clincher here, as the amount of depression (reciprocal to the inferior excessively discordant elevation) is almost equal to the height of the R wave. If you use the modified criteria, this ECG clearly meets the criteria.
@Chris, Tom and Dave,
ReplyDeleteI've never heard of the modified Scarbossa criteria before but find the preliminary data intriguing. Thanks for the info!
For those who would like to learn more, here are two good starting points: emcrit and prehospital 12 lead ECG.