50 - ACUTE CORONARY SYNDROME DURING LONG-TERM FOLLOW-UP OF KAWASAKI DISEASE

【Background】Coronary aneurysms due to Kawasaki disease (KD) may be complicated by severe stenosis and total occlusion. Most cardiac events occur within 2 years after the onset of KD, and coronary artery occlusion is often asymptomatic because of the development of collateral vessels. However, some patients of life-threatening myocardial infarction are in the chronic stage. This single-center study aimed to clarify the prognosis of coronary artery occlusion in KD.

【Methods and Results】We retrospectively reviewed 16 patients with KD that developed after 1985, who had regular follow-up after the acute phase and underwent acute myocardial infarction (AMI), asymptomatic chronic total occlusion (CTO), percutaneous coronary intervention (PCI), or coronary artery bypass graft surgery (CABG) in the chronic stage of KD. Patients with coronary artery occlusion in the acute phase were excluded. The median age of KD onset was 24 months (range, 5–137 months), 12/16 patients were men, median follow-up period was 18 years (range, 6–37 years), four patients underwent AMI, seven patients underwent CTO, three patients underwent PCI for stenotic lesions with ischemia, and two patients underwent CABG. The median time of events was 82 months (range, 9–280 months) after the onset of KD. Two of the four patients who underwent AMI had lesions in the right coronary artery (RCA) and were complicated by complete atrioventricular block (CAVB), one of which died and the other survived by emergency PCI. The remaining two patients had left anterior descending artery (LAD), and one of them had severe left ventricular dysfunction that ultimately led to heart transplantation. The time of AMI onset was 6–15 years after the onset of KD. The lesions that caused CTO were RCA in five and LAD in two. Of the 22 lesions that required intervention due to severe stenosis with ischemia or completely occluded lesions, 14 (64%) had giant aneurysms > 8 mm, and the remaining had medium aneurysms. All patients were taking antiplatelet agents, and 10/16 (63%) were taking warfarin.

【Conclusion】It is difficult to prevent coronary artery occlusion despite antiplatelet agents and warfarin. Symptomatic AMI develops in the chronic stage after KD, causing not only cardiac pump failure due to myocardial ischemia, but also sudden death due to CAVB because of impaired blood flow in the branch to the atrioventricular node from the RCA.