HPI: A 65-year-old man presents to the ED chest pain worse with sitting up and exertion. The following ECG is obtained:
Case ECG
Before watching the video, look closely at this ECG and ask yourself these questions:
- What ECG abnormalities do you notice?
- What is the most likely cause of the ST segment elevation seen?
- Would you activate the cath lab?
Subtle early signs of ischemia
- Early ischemia is often associated with…
- Hyperacute T-waves
- Disproportionately large T-waves (especially when larger than QRS)
- Straightening of the upslope of the T-waves
- “Checkmark or BAM sign”
- QRS complexes that lead straight into the T-wave with abnormal ST-segment morphology
- Reciprocal changes (e.g. aVL, V2)
- Especially aVL when the RCA is involved in inferior STEMI
- Anterior STEMI – reciprocal changes seen in ~ only 70%
- Beware, ~30% or more will NOT have reciprocal changes
- New upright T-wave in V1 (loss of precordial T-wave balance)
- When in doubt, get repeat ECGs!
Take-home Points:
- 30% of anterior STEMIs have no reciprocal ST segment depression
- Computers will often diagnose these as pericarditis, early repolarization or normal
- Don’t rely on reciprocal changes, especially in anterior STEMI’s
- Don’t trust the computer ECG interpretation, it will fool you!
Reference:
Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric. 6th Edition. Amazon link.
Kudos: Big thanks to Yisrael Pollack, Baruch Fertel for sharing their cases this week!
Notes: Questions for Amal? Email him at amalmattu@comcast.net or find him on Twitter @amalmattu.
