[Intraplaque hemorrhage: An underrecognized mechanism of coronary artery disease instability]

We report the case of a 49-year-old woman presenting with acute coronary syndrome caused by thrombotic occlusion of the left anterior descending artery, initially managed with thrombectomy and antithrombotic therapy without stent implantation. At one month, optical coherence tomography (OCT) showed healed plaque erosion without significant residual stenosis. Five months later, recurrent angina revealed rapid progression to severe stenosis, with OCT findings consistent with intraplaque hemorrhage, requiring stent implantation. This case highlights that a plaque with apparent surface healing may remain vulnerable and that intraplaque hemorrhage may represent an underrecognized mechanism of rapid plaque progression and coronary instability.