Characteristics of Pulmonary Atresia and Ventricular Septal Defect According to Morphologic Classification and Changes of Pulmonary Artery after Modified B-T Shunt / 소아과

ABSTRACT

PURPOSE: The purpose of this study is to help determine the optimal time and method for operation of pulmonary atresia(PA) with ventricular septal defect(VSD). METHODS: Seventy patients who were diagnosed as PA with VSD in the Pediatric Department of Cardiology, Severance Hospital between May, 1991 and April, 1995, were included in our study. Subjects were divided into two groups depending on the presence of major aorto-pulmonary collateral arteries(MAPCAs). In patients with MAPCAs, the distribution of MAPCAs concerning its relationship with central PA were analyzed, while in patients without them, morphologic changes of PA after performing conventional modified Blalock-Taussig(B-T) shunt were studied. RESULTS: After performing modified B-T shunts, the number of cases of PA stenosis and interruption increased from 26 to 37. Fifteen cases of advanced stenosis and six cases of interrupted PA were also observed. After performing modified B-T shunt, CSAI of both PA was increased from 197+/-101 to 311+/-138, more remarkably in cases without progression of PA stenosis. Among the patients with MAPCAs, 12 cases showed PDA, while 16 cases showed confluent PA. On average, MAPCAs were present in 2.5 cases. Concerning the types of MAPCAs, 14 cases were unifocal, while 36 cases were multifocal and most of them originated from descending aorta. CONCLUSION: In cases where pulmonary flow is maintained by PDA, stenosis of central PA is common, and can result in retarded pulmonary arterial development or increased stricture after modified B-T shunt, so careful attention is needed during follow-up. In cases with dominant MAPCAs, confluent PA is common, and multifocal pulmonary supply renders surgery difficult, so careful analysis of pulmonary supplies to each pulmonary segments, their shapes and relationships, are indicated preoperatively.