Suspected Syphilitic Left Main Coronary Ostial Stenosis Evaluated by Intravascular Ultrasound and Directional Coronary Atherectomy: A Case Report

A 49-year-old previously healthy man developed cardiopulmonary arrest during exercise caused by critical isolated left main coronary ostial stenosis.Positive syphilis serology and multimodality imaging suggested nonatherosclerotic vasculopathy.Intravascular ultrasound (IVUS) demonstrated a predominantly fibrous lesion with minimal lipid or calcification.Directional coronary atherectomy (DCA) was performed before stenting to obtain tissue for histopathologic evaluation, which revealed fibrous intimal thickening without features of atherosclerotic plaque.Alternative inflammatory and systemic vasculopathies were excluded.Although definitive histopathologic confirmation of syphilitic arteritis was unavailable, the integrated clinical findings supported this diagnosis and illustrate the value of tissue characterization in atypical coronary lesions.