Dr. Smith's ECG Blog

Instructive ECGs in Emergency Medicine Clinical Content

Associate Editors:
— Pendell Meyers & Ken Grauer (2018)
— Jesse McLaren & Emre Aslanger (2022)
— Willy Frick (2024) — Sam Ghali (2025)

editors

Anterior STEMI Evolves to de Winter’s T-waves

A middle-aged man called EMS for chest pain.

This prehospital ECG was recorded:

Obvious Anterior STEMI due to proximal LAD occlusion (with STE in aVL and reciprocal STD in inferior leads).

On arrival to the ED, this ECG was recorded 10 minutes later:

Almost all STE is gone, but the hyperacute T-waves remain

While waiting for the cath team, this was recorded 30 minutes after 2nd ECG:

Now there are classic de Winter’s T-waves.

This shows the dynamic nature of coronary thrombus.  Presumably, the thrombus had autolysis to a very small degree, allowing a trickle of blood flow through the LAD, enough to eliminate the ST elevation.

The patient was found to have a 100% proximal LAD occlusion.

By the time of the angiogram, which is never at the same the time as the ECG, there was not even a trickle of blood.

See this related post, with discussion of de Winter’s T-waves:

Is the LAD really completely occluded when there are de Winter’s waves?

Previous Article

Inferolateral STEMI: is there right ventricular MI also?

Next Article

Pre-existing Left Bundle Branch Block and Atrial Fib: what is alarming on this routine pre-procedure ECG?