Andersons pediatric cardiology 1081

FIG 41.8 Variation in size of the persistently patent arterial duct (doubleheaded arrows) (A) Relatively narrow lumen of the channel (B) Wide lumen of the channel The duct can also vary considerably in its shape Study of a large number of angiograms from patients with persistently patent ducts undergoing interventional closure at the Hospital for Sick Children, Toronto,40 showed that the most frequent pattern was to find a constriction at the pulmonary end of the duct This pattern was seen in two-thirds of cases In just less than 20%, a constriction was found at the aortic end of the duct, and in just less than 10% the lumen was unrestricted In just less than 5%, there was a constriction at both ends, and the remaining patients showed bizarre patterns not lending themselves to classification (Fig 41.9) Unique to the premature infant, the duct is elongated and unrestrictive, with a slight cranial angulation followed by a caudal turn as it connects to the pulmonary artery.41 FIG 41.9 Variation in morphology of the arterial duct noted from angiograms taken prior to interventional closure In the past, persistently patent arterial ducts were often the nidus for infectious endocarditis, but this complication is now extremely rare in developed countries Ducts could also become aneurysmal and elongated (Fig 41.10), but this is also now a rare finding, as is ductal rupture FIG 41.10 Lateral angiogram of a child with an elongated duct taken before transcatheter occlusion