Multiple coronary artery aneurysms in a young patient with Kawasaki disease and heterozygous familial hypercholesterolemia: A case study.

Kawasaki disease is an acute febrile systemic vasculitis affecting small and medium-sized arteries that predominately occurs in children and can result in coronary artery aneurysms. The etiology and pathogenesis of Kawasaki disease is unknown. Familial hypercholesterolemia (FH) is an autosomal dominant disorder that causes marked elevation in low-density lipoprotein (LDL) cholesterol and coronary atherosclerosis, and rarely coronary artery aneurysms and ectasia. A 20-year-old male presented with an acute ST-elevation myocardial infarction and was found to have coronary artery aneurysms affecting multiple vessels and thrombosis on coronary catheterization consistent with Kawasaki disease. Further investigation showed marked elevation of serum LDL cholesterol and genetic testing revealed a heterozygous pathogenic variant c.621C>T (p.Gly207=; rs121908044) in LDLR confirming FH. Over the next 11 years, despite oral anticoagulation and lipid lowering therapy, he had 3 episodes of myocardial infarction and continued to have angina requiring 2 coronary stents and coronary artery bypass graft surgery. This extremely rare association of multiple coronary artery aneurysms due to Kawasaki disease and heterozygous FH in a young patient has not been reported previously. Management of such patients is challenging and requires aggressive anti-coagulation to prevent coronary aneurysm thrombosis and LDL-cholesterol lowering to prevent atherosclerosis.