Arteries within the artery of coronary artery in an adult patient with acute coronary syndrome.

A 40-year-old man with acute coronary syndrome underwent coronary angiography, which showed a somewhat irregular contour with radiolucent lines in the left anterior descending artery. Intravascular ultrasound disclosed that the arterial lumen was separated by confining walls, yielding multiple inner lumens. Implantation of drug eluting stents resulted in slow coronary run-off, which was restored soon after intra-aortic balloon pumping support. The multiple inner lumens correspond to the histopathological finding of "arteries within the artery". While "arteries within the artery" is seen exclusively in children with a history of Kawasaki disease, it is rare in adults with undiagnosed Kawasaki disease.