Since September 1991, 14 consecutive patients with tetralogy of Fallot, pulmonary atresia, and diminutive pulmonary arteries have undergone staged repair. All patients had multiple aortopulmonary collateral arteries and the ductus arteriosus was absent in 11. Mean sizes of the right and left pulmonary arteries were 2.2 +/- 0.7 mm and 1.9 +/- 0.8 mm, respectively (range 0.5 to 3.0 mm). Eight patients (57%) have subsequently received complete repair. Age at initial procedure (shunt, right ventricle-pulmonary artery conduit, or direct aorta-pulmonary artery anastomosis) in this group was 5.3 +/- 6.8 months. The number of operative procedures to achieve complete repair was 2.9 +/- 0.8 per patient (range 2 to 4). Intraoperative postrepair peak right ventricle-left ventricle pressure ratio was 0.57 +/- 0.17. Six of 8 patients (75%) required additional interventional procedures (mean 1.5 +/- 1.2 per patient) for angioplasty of peripheral pulmonary artery stenoses, coil embolization of aortopulmonary collateral arteries, or intra-operative insertion of intravascular pulmonary artery stents. Mean follow-up from complete repair was 8.7 +/- 8.3 months (range 0.5 to 23.8 months) and is complete. There was one in-hospital death at 45 days, and one late cardiac death at 20.3 months. Six patients had initial palliative operations (unifocalization, right ventricle-pulmonary artery conduit, direct aorta-pulmonary artery anastomosis, or transannular outflow patch) but have not undergone complete repair. Age at initial procedure in this group was 27.9 +/- 56.9 months (range 0.27 to 155 months), and mean follow-up from initial procedure was 10.9 +/- 11.2 months (range 0 to 31.4 months). The operative mortality rate was 33% (2 of 6 patients). There was one late noncardiac death at 5.3 months. Three patients are awaiting further intervention or repair. This experience suggests that complete repair is feasible even in patients with extremely diminutive pulmonary arteries (< or = 3.0 mm). Pulmonary artery growth is facilitated by early (3 to 6 month) establishment of central pulmonary artery flow by right ventricle-pulmonary artery conduit (pulmonary arteries > 1.5 mm) or by direct ascending aorta-pulmonary artery anastomosis (pulmonary arteries < 1.5 mm). Subsequent interventional catheterization and operative procedures as required for pulmonary artery stenoses and coil embolization of collateral arteries allow continued recruitment of central pulmonary arteries and may obviate or minimize the need for unifocalization procedures.