Evolving strategies and improving outcomes of the modified Norwood procedure: A 10-year single-institution experience

Background. This study reviews our 10-year experience with the modified Nor wood procedure to determine its early and midterm outcomes. The focus is on the impact of evolving management strategies and accumulated institutional experience. Methods. A modified Norwood operation was performed in 171 infants over a 1 0-year period. Sixty-eight percent of the infants were male, the median age at operation was 6 days (range 1 to 175 days), and the median weight was 3 .3 kg (range 1.7 to 4.8 kg). The 10-year period was divided into three eras : era I, 1990 through 1993; era II, 1994 through 1997; and era III; 1998 in to 2000. Outcomes and risk factors for mortality were sought. Results. Hypoplastic left heart syndrome or a variant was the primary diagn osis in 118 infants (69%). The overall 5-year survival rate was 43%. Multiv ariate analysis revealed that only need of preoperative ventilatory support , earlier date of operation, and lower weight at operation were significant independent predictors of increased time-related mortality. Morphologic fe atures such as a diagnosis other than hypoplastic left heart syndrome, asce nding aortic size, and noncardiac anomalies were not significantly associat ed with an increased risk of death. The hospital survival rate for stage-on e palliation in era III was 82%, significantly better than that in the prec eding eras (p < 0.001). Attrition between stages one and two accounted for a 15% mortality rate among hospital survivors. Conclusions. With increasing experience and improvements in perioperative c are and surgical technique, good outcomes can be expected for the first-sta ge modified Norwood procedure. Greater monitoring of patients in the inters tage period may reduce interval mortality and improve overall survival. (C) 2001 by The Society of Thoracic Surgeons.