A 9-year-old boy was suspected truvisionhealthftp.com of having acute myocardial infarction and emergency coronary angiogram was performed.No signs of flow limitation in either coronary artery was detected.We performed intravascular ultrasonography from the ascending aorta, which showed a ridge on the left main trunk read more acting like a valve, resulting in significant stenosis.Percutaneous coronary intervention with stent deployment was performed with good result.