A case of repetitive acute coronary syndrome in a patient with familial hypercholesterolemia

Abstract The low-density lipoprotein-cholesterol (LDL-C) level of a 60-year-old woman diagnosed with acute coronary syndrome (ACS) was 212 mg/dL. She was suspected of having familial hypercholesterolemia, therefore, administration of a proprotein convertase subtilisin-kexin type 9 (PCSK9) antibody in addition to atorvastatin plus ezetimibe was initiated, reducing her LDL-C level to 42 mg/dL. Nine months after initial ACS, the PCSK9 antibody was discontinued. Six months after the iturruption, she relapsed with ACS, and neoatherosclerosis progression was confirmed via intravascular ultrasound. Then, the PCSK9 antibody was reintroduced. Disruption of a PCSK9 may be associated with the progression and destabilization of neoatherosclerosis.