Transposition of the Great Arteries After Arterial Switch Operation

The aorta in transposition of the great arteries (TGA) has unique anatomical and operative features; the pulmonary valve and root are used to form the neo-aortic valve and root, and the aortic root undergoes surgical insult with the arterial switch operation. Aortopathy, defined as aortic root dilatation caused by abnormalities in aortic pathophysiological function with low coronary artery flow and systemic ventricular dysfunction, is a clinically important sequel in TGA patients. Despite variation between individuals, aortopathy generally progresses with age; aortic root dilation is progressive, and aortic distensibility and freedom from significant aortic regurgitation (AR) decrease with age. Although aortopathy in TGA seems not as severe as that following the Ross operation, some patients with marked aortic root dilation or severe AR require repeat operations. Research on aortopathy in TGA is currently accumulating information on the nature of the aortopathy, individual risk and protective factors, and anatomical, histological, and functional characteristics. Because of the progressive nature of aortopathy, further longer serial follow-up data need to be accumulated to clarify life-span prognosis of aortopathy and develop effective therapeutic strategies to prevent/ameliorate aortopathy in TGA patients.