Histological examination revealed acute myocardial infarction in the anterior wall and ventricular septum, with in-stent occlusive thrombosis overlying neoatherosclerosis in the left anterior descending artery. Dense neutrophilic infiltration was observed in the ruptured plaque and the media, and neutrophilic endarteritis and plaque erosion were also identified in non-culprit coronary arteries. The findings suggest that sepsis-associated vascular inflammation may promote diffuse coronary endothelial injury and plaque instability.