INTERMEDIATE RESULTS AFTER COMPLETE REPAIR OF TETRALOGY OF FALLOT IN NEONATES

From July 1988 through September 1993, 30 neonates with symptomatic te tralogy of Fallot underwent complete repair. Sixteen patients had tetr alogy and pulmonary stenosis, 9 had pulmonary atresia, 3 had nonconflu ent pulmonary arteries, and 2 had both pulmonary atresia and nonconflu ent pulmonary arteries. The median age at operation was 11 days (mean +/- standard error of the mean, 12.6 +/- 2.9 days), with a mean weight of 3.1 +/- 0.1 kg (range 1.5 to 4.4 kg). Preoperatively, 14 patients were receiving an infusion of prostaglandin, 13 were mechanically vent ilated, and 6 required inotropic support. Right ventricular outflow tr act obstruction was managed by a limited transannular patch in 25 pati ents, infundibular muscle division with limited resection in 15, and i nsertion of a right ventricle-pulmonary artery valved aortic homograft conduit in 5 patients. Follow-up was complete at a median interval of 24 months (range 1 to 62 months). There were no hospital deaths and t wo late deaths, for 1-month, 1-year, and 5-year actuarial survivals of 100%, 93%, and 93%, respectively. The hazard function for death had a rapidly declining single phase that approached zero by 6 months after the operation. Both late deaths occurred in patients with tetralogy o f Fallot and pulmonary atresia who had undergone aortic homograft cond uit reconstruction, so that the only independent risk factor for death was the use of a valved homograft conduit (p less than or equal to 0. 005). Eight patients required reoperation, resulting in 1-month, 1-yea r, and 5-year freedom from reoperation rates of 100%, 93%, and 66%, re spectively. Indications for reoperation were branch left pulmonary art ery stenosis in 5 patients, residual right ventricular outflow tract o bstruction in 2 patients, and severe pulmonary insufficiency in 1 pati ent. Independent risk factors for reoperation included an intraoperati ve pressure ratio between the right and left ventricles of 0.75 or gre ater (p = 0.01), Doppler residual left pulmonary artery stenosis of 15 mm Hg or more, or Doppler right ventricular outflow tract obstruction gradient of 40 mm Hg or more at hospital discharge (p = 0.002 and 0.0 2, respectively). This series demonstrates the safety of early hemodyn amic repair of symptomatic tetralogy of Fallot in neonates. It also em phasizes the importance of relieving all sources of right ventricular outflow tract obstruction at the initial operation, particularly that located at the site of insertion of the ductus arteriosus, which may b e difficult to diagnose in the neonate before ductal closure occurs. T he safety and efficacy of valved aortic homograft conduits in neonates requires further investigation.