Atypical Chest Pain Revealing a Coronary Artery Dissection on an Atherosclerotic Plaque

Coronary artery dissection overlying atherosclerotic plaque represents a rare but important mechanism of acute coronary syndrome (ACS). It differs from spontaneous coronary artery dissection (SCAD), which typically occurs in angiographically normal arteries. Recognizing this distinction is critical for optimal management and reporting. We report the case of a 53-year-old diabetic male who presented with atypical chest pain. ECG showed nonspecific repolarization changes, and troponins were mildly elevated. Coronary angiography, performed 12 hours after symptom onset, revealed a significant stenosis and dissection at the bifurcation of the mid-left anterior descending (LAD) artery and diagonal branch. Atherosclerotic plaque was evident at the dissection site. No intravascular imaging was available to further confirm plaque disruption. The patient was treated with a provisional stenting strategy using a drug-eluting stent (DES), with excellent angiographic and clinical outcomes. Coronary artery dissection occurring on a vulnerable atherosclerotic plaque is a rare but clinically relevant cause of ACS. Differentiation from SCAD is essential, as it has distinct pathophysiology, prognosis, and therapeutic implications. This case highlights the need for refined classification systems and dedicated guidelines addressing plaque-related dissections.