Vascular Wall Morphology and Vascular Elasticity of Coronary Aneurysms in Long-term after Kawasaki Disease: Intravascular Ultrasound Study

Abstract

The coronary artery (CA) lesion in Kawasaki disease (KD) may be a long term coronary risk factor. We examined the CA wall morphology and elasticity of CA itself using intravascular ultrasound (IVUS) imaging in 70 KD patients (pts) and 10 controls. Consecutive KD pts were followed over more than 10 years from KD onset. The 70 pts comprised 4 groups: Group 1:18 pts with persistent aneurysms. Group 2: 18 pts with CA stenosis. Group 3: 28 KD pts with regressed CA aneurysms, Group 4: 6 pts with normal CA angiography findings at the acute stage of KD. We carefully examined the CA wall morphology on IVUS imagings. The % area change (%AC) of CA lumen in one cardiac cycle was calculated using IVUS imaging to examine the elasticity of the CA wall. The IVUS imaging in Groups 1 and 2 showed intima hyperplasia and various degree of calcification at sites of both persistent coronary aneurysms (intima-media complex (IMC):0.71± 0.22mm, % calcification area (%CA):55.4± 21%) and stenosis (IMC:0.88± 0.44mm, %CA:81.4± 20%,). However, IVUS imaging in Group 3 showed various degrees of the intimal thickening without calcification (IMC:0.48± 0.12mm, %CA:0 %). All IVUS findings in the Group 4, the CA wall echo had a single layered appearance, were similar to that in the control pts. In Group 1 and 2, the CA demonstrated poor elasticity, almost no change in the lumen area (%AC, Group 1:2.4± 1.9%, Croup 2:0.8± 1.5%). In Group 3, A significant poorer elasticity was fond compare to the control pts (Group 3:8.1± 3.7% vs. control 22.0± 13.2%, p<0.05). Group 4 showed no significant difference of elasticity of CA from control (Group 4:21.2± 11.3%). We conclude that long-term persistent coronary aneurysm and regressed coronary aneurysms after KD have abnormal vascular wall morphology and poor vascular elasticity.