Use of Proprotein Converse Subtilisin/Kexin Type 9 Inhibitor to Treat Cholesterol Crystal Embolisms after Catheterization: A Report of Three Cases

Cholesterol crystal embolism (CCE) is a serious complication that occurs after cardiac and vascular procedures. CCE involves multiple organs, and the prognosis and renal function of patients is poor. Although the efficacy of steroid, statin, and low-density lipoprotein apheresis has been reported, no definitive treatment has been established. We herein report three consecutive cases treated with conventional steroid therapy with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor after catheterization. The renal function was preserved, steroid therapy was stopped, and wound healing of blue toes was achieved. PCSK9 inhibitor therapy was safe in the present patient and may be a potential treatment option for CCE.