Neoaortic root dilation associated with left coronary artery stenosis following arterial switch procedure

We describe a patient who was diagnosed with d-transposition of the great arteries, with intact ventricular septum, who underwent arterial switch procedure on day 5 of life. Over the subsequent years, he developed progressive neoaortic root dilation with a Z score of up to 7.2. At 5 years of age, he presented with myocardial infarction. Cardiac catheterization demonstrated a markedly dilated aortic root with kinking and stenosis of the left main coronary artery into the left anterior descending coronary artery. He underwent emergency left internal mammary artery bypass grafting to the left anterior descending coronary artery. Although he required left ventricular assist device (LVAD) support in the early post-operative period, he recovered with a left ventricular ejection fraction of 52% on the most recent follow-up.