De Winter syndrome and ST-segment elevation myocardial infarction can evolve into one another: Report of two cases.

Background: The de Winter electrocardiography (ECG) pattern is a sign that implies proximal left anterior descending coronary artery occlusion in patients with chest pain. The previous view was that the de Winter ECG pattern is static.

Case Summary: A 65-year-old man presented with sudden chest pain at rest associated with diaphoresis for 55 min. The first ECG showed only T-wave inversion in III and aVF leads. Another ECG was performed at the 100 minute, showing upsloping ST segments depressed with tall and symmetrical T waves in the precordial leads; the J point was raised by 0.1 mV at the aVR lead. The patient was referred to our catheterization laboratory. A third ECG showed ST segment elevation by 0.2 mV in the I and aVL leads. The patient underwent emergency coronary angiography, which revealed complete proximal left anterior descending coronary (LAD) occlusion. The second patient presented with a 1-h history of sudden-onset, severe, substernal crushing chest pain. The first ECG showed ST-segment elevation (0.1-1.7 mV) in I, aVL, and precordial leads. The patient was referred to the catheterization laboratory. On arrival, his symptoms alleviated, and ECG showed that the ST-segments had significantly fallen back. The third ECG showed a typical de Winter pattern. Coronary angiography revealed 99% stenosis of the middle LAD.

Conclusion: The de Winter ECG pattern is transient and dynamic, and it reflects proximal or mid-LAD subtotal occlusion rather than total occlusion.