Beyond ST Elevation: Recognizing Wellens Syndrome and the de Winter Pattern as High-Risk LAD Ischemia

High-risk left anterior descending (LAD) artery disease does not always present with classic ST-segment elevation on an electrocardiogram (ECG), leading to under-recognition of critical ischemia in acute coronary syndromes. Wellens syndrome and the de Winter ECG pattern are 2 important markers of proximal LAD disease that may present without the expected ST-segment elevation. Although traditionally described as separate entities, they are increasingly recognized as representing different phases along a shared spectrum of anterior ischemia. Wellens syndrome is generally associated with a reperfusion state characterized by T-wave abnormalities in the anterior leads, often identified when patients are no longer in active pain. In contrast, the de Winter pattern reflects ongoing LAD occlusion, with upsloping ST-segment depression and prominent T waves, and is usually seen while the patient is still having chest pain. Although these patterns present differently, both point to unstable coronary disease and carry a real risk of progression to an anterior myocardial infarction. What makes them challenging is that they can be easy to miss, as patients may have only mild biomarker changes, lack classic ST-segment elevation, or even seem to be improving clinically at the time of evaluation. Recognizing these patterns and understanding how they relate to 1 another can help make ECG interpretation more consistent in cases of anterior ischemia. This review focuses on the evolving continuum between the de Winter and Wellens syndromes and their pathophysiology with the goal of improving early recognition and guiding timely management.