Dramatic Coronary Artery Aneurysm Regression After Coronary Artery Bypass Grafting and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitor Therapy.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors offer clinical benefits by reducing low-density lipoprotein cholesterol levels and have emerged as valuable therapeutic agents for the management of cardiovascular diseases. Although their effectiveness in treating coronary artery plaques and abdominal aortic aneurysms has been reported, data on their effects on coronary artery aneurysms are limited. Herein, we report the case of a 43-year-old man with familial hyperlipidemia who presented with angina pectoris caused by a giant right coronary artery aneurysm accompanied by extensive plaques and severe stenosis. The patient underwent coronary artery bypass grafting at 6 anastomotic sites, and a PCSK9 inhibitor was initiated postoperatively. Five years after surgery, imaging demonstrated a gradual reduction in the size of the coronary artery aneurysm, and 8 years later, the size was further reduced. This case report illustrates the rare clinical course of a coronary artery aneurysms.