November 10, 2015 by dailybolusoflr
By: Erin Kane, MD
How do you know you need one?
- All inferior STEMIs should have a right-sided EKG done (at least V4R)
- Two clues in inferior STEMI that there is RV infarction:
- ST segment elevation in lead V1
- ST elevation in lead III>lead II
- RV infarction is associated with hypotension (preload sensitive)
What is the relevant anatomy?
- RV infarction is associated with 40% of inferior infarctions
- May complicate some anterior infarctions
- Rarely isolated phenomenon
- Affected vessels: usually RCA proximal to right ventricular marginal branches
- Less commonly circumflex
How do you place the leads to get it?
- Record V4R for all inferior STEMIs – most sensitive
- V4R electrode is placed over right fifth intercostal space in mid-clavicular line
How do you read it?
- ST elevation in V4R has sensitivity of 88% for diagnosing RV MI (78% specificity, diagnostic accuracy 83%)
Anatomical relationship of leads
- Inferior wall – Leads II, III, and aVF
- Anterior wall – leads V1 to V4
- Lateral wall – Leads I, aVL, V5, V6
- Posterior wall – Leads V7 to V9
- Right ventricle – Right sided chest leads V1R to V6R
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4. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, Seventh Edition