Arterial duct morphology with reference to angioplasty and stenting

We studied the angiographic morphology of the arterial duct in neonates with congenital heart diseases. We defined the variations in ducto-aortic angle, number of tortuosities and site of insertion into the aorta of the duct in five diagnostic groups: (i) patent arterial duct (unobstructed) (n = 27), (ii) coarctation of the aorta (n = 24), (iii) pulmonary stenosis (n = 23), (iv) pulmonary atresia (n = 19) with or without ventricular septal defect, (v) hypoplastic left heart syndrome (n = 3). In the patent arterial duct group the angles ranged from 80 to 139 degrees, mean 107 degrees; in the coarctation group, 76 to 136 degrees, mean 104 degrees; in the pulmonary stenosis group, -60 to 111 degrees, mean 43 degrees; in the pulmonary atresia group, -55 to 115 degrees, mean 25 degrees; in the hypoplastic left heart syndrome 92 to 105 degrees, mean 98 degrees. The angles for the pulmonary atresia and stenosis groups were significantly less than those for the coarctation and patent ductus groups (P < 0.001). A ventricular septal defect in patients with pulmonary atresia or pulmonary stenosis was significantly associated with a smaller angle, a more proximal and a more tortuous duct (P < 0.01). The varying morphology of the duct in neonates with congenital heart lesions, especially with right heart obstruction requires special attention when attempting catheter techniques of ductal stenting. In particular the angle of approach and the presence of tortuosities may increase the difficulty of endovacular stenting.