Late postoperative pulmonary vascular resistance in patients with tetralogy of Fallot and pulmonary atresia

: Twenty-two patients with tetralogy of Fallot and pulmonary atresia underwent cardiac catheterization and angiocardiography late after repair. In ten patients, the disease was not associated with the major aortopulmonary collateral artery (MAPCA), but in 12 patients, the disease was associated with it. Three patients died after restudy, two because of pulmonary hypertension and one because of pneumonia. Pulmonary artery mean pressure was 15-92 (28 +/- 21) mmHg, being higher in 75% of the patients with MAPCA than the normal range. The number of pulmonary artery subsegments connected to the central pulmonary arteries was determined from pulmonary arteriography, being 22-42 (38 +/- 6). Pulmonary artery mean pressure and pulmonary vasculature resistance (PVR), 0.8-35.2 (10 +/- 9), inversely correlated with the number of the centrally connected pulmonary artery subsegments (r = -0.81, p less than 0.001 vs PAP, r = -0.85, p less than 0.001 vs PVR). PVR per subsegment also inversely correlated with them (r = -0.81, p less than 0.001). These findings suggest that pulmonary vasculature resistance is abnormally high in this disease, and increase as the number of the centrally connected pulmonary artery subsegments decrease.