[Tetralogy of Fallot with anomalous origin of unilateral pulmonary artery].

Between 1971 and 1988, 7 patients (pts) of TOF with anomalous origin of unilateral pulmonary artery (AOPA) underwent intracardiac repair at Tohoku University Hospital. They were 2 males and 5 females, with ages ranging from 4 to 26 years old. The right PA originated from the RV in all cases, whereas the left PA originated from the ascending aorta in 2 pts (Group 1) and from the ductus arteriosus in 5 pts (Group 2 & 3). In Group 2 (2 pts), the left PA was separated from the right PA with intraluminal membrane. In Group 3 (3 pts), there was no communication between both pulmonary arteries. The left PA was reconstructed in Group 1 & 2. However, it was impossible to reconstruct the left PA in Group 3 since the ductus arteriosus and left PA had been occluded before intracardiac repair. In Group 3, VSD was closed with one-way (RV----LV) valved patch for the aim of lowering RV pressure. Postoperative RV/Ao pressure ratio was 0.5-0.8 in the cases of Group 1 & 2, 0.8-1.0 in Group 3. Three patients (one in each group) died postoperatively due to low output syndrome. Autopsy revealed pulmonary vascular obstructive disease (PVOD) of the left lung in Group 1. It is concluded that TOF with AOPA should be corrected before the advance of PVOD in case PA originate from the ascending aorta, and before the occlusion of the ductus in case PA originate from it, in order to prevent postoperative RV overload.