ST depression in the right precordial leads can be anteroseptal ischemia, but it can also be a posterior STEMI. What are the clues to posterior STEMI?

• tall R waves in these leads is highly suggestive of posterior STEMI
• upright T-waves in these leads is also suggestive of posterior STEMI

Posterior leads (a couple of leads placed in the left mid-back area below the tip of the scapula) can help confirm posterior STEMI if there's STE in those leads. If there's no STE, call it just ischemia!

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