Estudo angiográfico da circulação pulmonar na tetralogia de Fallot com atresia pulmonar

Abstract

Approximately 85% of the patients with tetralogy of Fallot associated with pulmonary atresia have anomalies of the pulmonary vascular tree. The pulmonary arteries are usually of a small caliber, often nonconfluent, and not connected to the right ventricle. In many cases, the proximal branches are stenotic, hypoplastic, or totally absent. The aortopulmonary collateral arteries are frequently present and may supply partially or almost totally the pulmonary blood flow.The treatment aims at establishing the confluence, normalizing the caliber and distribution of the pulmonary arteries, which may be obtained through the use of shunts and unifocalization of those vessels. Several procedures are usually required before the definitive correction [1][2][3][4] . Dilation with a balloon catheter and use of stents in the pulmonary arteries may represent an important factor for the success of treatment [5][6][7] . The operative risk ranges from 0 to 20% depending on the number of shunts and thoracotomies before the definitive correction, which is only possible in 60 to 70% of patients 3,4 . Recently, some researchers have adopted a radical approach with complete pulmonary arterial reconstruction, closure of the interventricular communication, and placement, in the neonatal period [8][9][10] , of a tube in the right ventricular outflow tract. Although the operative risk has been described as small, this approach requires more complex surgical techniques and experience of the surgical team, which are available only in certain centers 11,12 . This study aimed at demonstrating the importance of the angiographic study of the pulmonary blood supply in selecting patients with tetralogy of Fallot and pulmonary atresia for total or partial correction of that malformation. MethodsFrom 1980 to 2000, 82 patients with tetralogy of Fallot and pulmonary atresia were studied from the hemodynamic and cineangiocardiographic points of view. Twenty-six patients with pulmonary atresia associated with complex cardiac malformation (single atrium, single ventricle, single AV valve, and single outflow tract -pulmonary atresia) were excluded. The remaining 56 patients were between 20 days and 4 years of age, and their weights ranged from 1.7 kg to 10 kg. The pulmonary blood supply was studied by using the following methods: aortography with occlusion of the thoracic aorta with the Berman angiographic catheter 13 ConclusionThis type of approach enables the obtainment of information necessary for the correct clinicosurgical management of patients, due to the great complexity and extreme variability of the pulmonary blood supply in tetralogy of Fallot with pulmonary atresia.

Correlating computed tomographic angiography of pulmonary circulation with clinical course and disease burden in patients with tetralogy of Fallot and pulmonary atresia

“…In addition, patients with pulmonary atresia have a significant smaller size of PAs than patients with TOF. Our results are different from a previous study which reported the angiographic classification of the pulmonary circulation in 56 patients with pulmonary atresia, which found that the most common pulmonary circulation was type 1 with the presence of ductus arteriosus [ 5 ]. In addition, our study found a higher incidence of incomplete arborization of PAs than the previous study (53 % vs 29 %) [ 5 ].…”

“…Our results are different from a previous study which reported the angiographic classification of the pulmonary circulation in 56 patients with pulmonary atresia, which found that the most common pulmonary circulation was type 1 with the presence of ductus arteriosus [ 5 ]. In addition, our study found a higher incidence of incomplete arborization of PAs than the previous study (53 % vs 29 %) [ 5 ]. The discrepancy in results may be related to geographic differences in the pattern of pulmonary circulation among the Asian and South American study population and the different numbers of the study population ( N = 85 vs 56).…”

“…Embryology suggests that MAPCAs are congenital systemic arterial collaterals originating from the persistent intersegmental arteries which should normally regress once the connection between the central and intraparenchymal pulmonary arteries (PAs) has been established [ 3 , 4 ]. Approximately 85 % of MAPCAs are found in patients with TOF-PA [ 5 ]. MAPCAs are also developed in TOF.…”

“…Pulmonary circulation in patients with TOF and TOF-PA is derived from PAs and/ or MAPCAs. The native PAs can vary from mild hypoplasia to absence of a branch or all PAs, and from confluent to non-confluent PAs [ 5 , 7 ]. MAPCAs could be an additional source of pulmonary perfusion aside from the native PAs.…”