“56-year-old man with chest discomfort and SOB”
Would you call a STEMI alert?
YES! This is an acute anterolateral STEMI occurring with a RBBB. Unlike its cousin, a LBBB, a RBBB does not obscure ischemia and infarct patterns. Again, it is important to be familiar with some expected repolarization changes with a RBBB (essentially T-wave inversion in V1-3, leads with the most obvious depolarization changes).
This EKG is impressive for the ST-segment elevation in leads V2-4, including “giant R waves” in V4-5, the earliest signs of STEMI. There does seem to be subtle, probably early, reciprocal ST-segment depression in the inferior leads, supporting the diagnosis of STEMI.
If you were questioning, or not embracing, this unique and fairly rare EKG of a RBBB with an acute STEMI, look at the second EMS transmission that occurred 10 minutes later…
ST-segment elevation in V2-5, as well as ST- and T-wave changes in I, aVL and V6; notice also the T-wave inversion in III, a reciprocal change to the anterior-lateral infarct.