Aortic dilatation in complex congenital heart disease

Dilation of the ascending aorta in congenital heart diseases (CHD) may exceed hemodynamic or morphogenetic expectations, or the aorta may become aneurysmal and rupture (1,2). Aortic dilation in Marfan syndrome, bicuspid aortic valve and coarctation of the aorta (COA) is well documented, and these disorders are associated with ascending aortic and/or para-coarctation medial degeneration (3,4). CHD, such as single ventricle with pulmonary stenosis/atresia, truncus arteriosus communis (TAC), complete transposition of the great arteries (TGA), hypoplastic left heart syndrome (HLHS), tetralogy of Fallot (TOF) and the Fontan procedure, are also associated with aortic medial degeneration and aortic dilatation (1). These observations led us to hypothesize that many CHD cause aortic medial degeneration that reflects a common developmental fault, which weakens the aortic wall