The morphology of aortopulmonary windows with regard to their classification and morphogenesis

Abstract

AbstractWe examined 25 heart specimens with aortopulmonary windows in order to review the variety of the lesion and its associated malformations. Unlike common arterial trunk, the aortopulmonary window involves a deficiency of the wall of the ascending aorta and that of the pulmonary trunk. The window was in proximal position in three specimens, intermediate position in three specimens, distal position in 16 specimens and was confluent in three specimens. The size of the window varied from 27 to 100% of the total length of the pulmonary trunk but size did not bear any apparent relationship to the position of the defect. The shape of the window was tunnel-like in one case. Of the 16 specimens with distal windows, the orifice of the right pulmonary artery arose from the aorta in seven specimens and was overriding the plane of the window in one specimen. The window occurred as an isolated lesion in four specimens. It was associated with interruption of the aortic arch at the isthmus in eight specimens and between the left carotid and left subclavian arteries in three specimens. A further three specimens had isthmal stenosis. Among the other associated defects were complete transposition (two specimens), tetralogy of Fallot (one specimen), and double outlet right ventricle (one specimen). A ventricular septal defect was present in six of the 25 specimens. The associated lesions found with aortopulmonary window are seldom encountered with common arterial trunk, suggesting these two arterial lesions have different pathogenesis and are not variants of the same entity.