All issues > Volume 31(9); 1988

Original Article

J Korean Pediatr Soc. 1988;31(9):1139-1145. Published online September 30, 1988.

An Agiographic Study on Developemental and Spatial Relationship of Patent Ductus Arteriosus (PDA) and Aortic Arch in Right Ventricular Outflow Tract (RVOT) Obstruction.

DO Hyun Kim¹, Youn Mo Ahn¹, Ha Balk Lee¹, Kyoo Hwan Rhee¹, Hahng Lee¹, Seok Chol Jeon²

¹Department of Pediatrics, College of Medicine, Hanyang University, Seoul, Korea
²Department of Radiology, College of Medicine, Hanyang University, Seoul, Korea

Received: December 31, 1987;  Accepted: March 16, 1988.

Abstract

Ductus arteriosus plays important hemodynamic role in fetal development, and establish a certain spatial relationship with aorta. Although ductus arteriosus normally closes after birth, it could remain patent alone, or in association with various congenital heart anomalies. In these patients the develop- mental hemodynamic changes may result in the specific variation in the spatial relationhip of patent ductus arterisus (PDA) and aortic arch. The developmental significance of the size of aorta and the angle of ductus arteriosus and descending aorta was studied in PDA in association with various types of congenital heart anomalies, with special emphasis on the effect of existing ventricular septal defect in the patient group with right ventricular outflow tract (RVOT) obstruction. For this purpose, 23 cases of PDA confirmed by cardiac catheterization and angiography at Hanyang University Hospital during the period of 4 years from April, 1983 to March, 1987 were analyzed based on the angiographic findings, and in each case the inferior angle of ductus arteriosus and the descending aorta was measured as well as the diameter of aorta. The summary of the study and the observtion is as follows: 1) The mean inferior angle of the ductus arteriosus was 61.7° in ROVT obstruction with VSD group (6 cases), 92O in RVOT obstruction with intact ventricular septum (1 case), 117° in PDA associated with TGA (5 cases), 117.5° in PDA associated with VSD but without RVOT obstruction and 126° in isolated PDA group (5 cases). 2) The aorta did not show the isthmic narrowing in RVOT obstruction group whether the VSD was present or not. 3) In pulmonary atresia with intact ventricular septum the blood flow was maintained normal through the ductus and the inferior angle of the ductus arteriosus remained obtuse. In this group the findings suggest the possibility that the obstructive phenomenon probably developed in the later part of fetal life. 4) In pulmonary atresia with VSD group the flow of the ductus was reversed form left to right, and the ductus might have developed poorly and the inferior angle of the ductus arteriosus was acute. In this group the findings suggest the possiblity that the RVOT obstruction probably occurred in earlier part of fetal life. 5) These observations are not only important for understanding the develpmental process of the ductus in RVOT obstruction but also for early recognition, correct diagnosis and aggressive manage- ment. The aortographic features of a normal sized ductus arteriosus with an obtuse inferior angle do not exclude the possibility of pulmonary atresia. In this case right ventricle is not hypoplastic and shows the continuity of the right ventricle with the pulmonary artery.

Keywords :Ductus arteriosus, ROVT obstruction, inferior angle