Results of surgical treatment for pulmonary atresia.

Most cases of pulmonary atresia have the general anatomical features of Fallot's tetralogy with atresia at or near the pulmonary valve instead of stenosis, but in one quarter of the necropsy cases the ventricular septum is intact instead of having a defect (24%, Peacock, 1866, and Abbott, 1936). The general features, based on six cases with necropsy, have been discussed by Allanby et al. (1950): five of these were of the common type and one of the less common type. Subsequent experience has made us think that the latter is even less common than this, since it was found in only one of our fourteen necropsies, perhaps because our experience is with older children. The clinical features are like those of Fallot's tetralogy. East and Barnard (1938) thought that the diagnosis should be made more often on clinical grounds, and Taussig (1947) emphasized the loud single (aortic) sound well-heard in the pulmonary area and the absence of a systolic murmur. The circulation to the lungs must come from the aorta through a persistent ductus or enlarged bronchial arteries, more often the latter. In about half the cases there is a continuous murmur from some of these vessels, but in the other half no such murmur is heard, perhaps because the circulation to the lungs is maintained by a large number of smaller arteries. The shadows in the lungs from the numerous bronchial arteries, seen both with ordinary radiology and even more clearly with angiocardiography, are the other main diagnostic feature: they have been described by Campbell and Gardner (1950). The absence of the hilar comma that represents a properly filled pulmonary artery (Fig. 1 and 2), often replaced by some unusual artery (Fig. 3), and the deep, rounded pulmonary bay, often with unusually sharp definition, indicate an anomalous pulmonary blood supply. Dense vascular shadows, high in the mediastinum, sometimes best seen below the aortic arch in the left anterior oblique position with angiocardiography, and nodular hilar structures with unusual branching in the lung fields are good evidence of hypertrophied bronchial arteries. The commoner form of pulmonary atresia has been considered as a variety of Fallot's tetralogy. In a follow-up of patients after subclavian-pulmonary anastomosis (Campbell and Deuchar, 1953) we included 20 such cases: the high mortality and relatively poor results made us doubtful about the advisability, of operation, but a few results were so good that it can not be discarded. Taussig and Bauerfeld (1953) and White et al. (1956) also found the results less good than those for Fallot's tetralogy. The special problems involved in the surgical treatment of pulmonary atresia-the small thinwalled pulmonary artery that is often unsuitable for an anastomosis, and the importance of not dividing too many of the small collateral vessels that carry the main blood supply to the lungsmade us think that pulmonary atresia should be recognized as a separate entity and should not be included with Fallot's tetralogy (Allanby et al., 1950). In a more recent follow-up of the results of operation for Fallot's tetralogy (Campbell, 1958), we excluded them, so are considering them here.