de Winter Electrocardiographic Pattern Caused by Diagonal Branch Lesion

Abstract A woman in her 50s developed acute coronary syndrome with de Winter pattern electrocardiogram (ECG). A coronary angiography revealed diagonal branch lesion caused by spontaneous coronary artery dissection, whereas the left-anterior descending artery was intact. The ECG change was transient and returned to normal without treatment 2 h later. (Level of Difficulty: Beginner.)