Does Bilateral Pulmonary Artery Banding in Norwood Patients Adversely Affect the Branch Pulmonary Artery Size? An Outcome Comparison with Primary Norwood Patients

Objectives: Bilateral pulmonary artery banding (PAB) is an initial palliation option in the management of single ventricle patients including hypoplastic left heart syndrome (HLHS). PAB yields good results especially in high-risk HLHS patients. However, there is concern with pulmonary artery growth after PAB. In addition, it has been speculated that longer duration of PAB might have a more pronounced negative effect on PA size.

Methods: The aim of this study was to analyze the outcome after PAB versus initial Norwood (iNW) operation. Between 2002 and end of 2017, a total of 308 Norwood procedures were performed in our institution: 273 as primary Norwood operations and 35 (11.4%) after initial PAB. The comprehensive Aristotle risk score was significantly higher in the PAB group (20.7 ± 3.05 vs. 18.0 ± 2.48: iNW). The duration of the PAB ranged from 2 to 173 days with a median of 37 days. Pulmonary artery size was evaluated by calculation of total lower lobe index (TLLI) from angiographic images before bidirectional Glenn operations.

Results: Total mortality was not significantly different between the groups despite more high-risk patients in the PAB group. Early and late mortalities were 57/273 (20.9%) in the iNW group versus 7/35 (20.0%) in the PAB group (p = 0.89). Mortality from birth up to 30 days after Norwood was 10.3% in the iNW group compared with 8.6% in the PAB group (p = 0.9). Estimated Kaplan–Meier survival at 1 year was not statistically different between the two groups. The mean TLLI before BGD was 155 ± 38 mm²/m² in the PAB group and 161 ± 29 mm²/m² in the iNW group (p = ns). There was no inverse correlation between longer duration of the PAB and PA size. Comparing patients with a PAB up to 1 month versus over 1 month, in the latter group, we found a trend to more left PA plasties (p = 0.06).

Conclusion: Bilateral pulmonary banding with or without ductal stenting is an effective technique to reduce the operative risk in higher risk Norwood patients. In our institution, this is followed by a Norwood operation after a few weeks. We found in this analysis that short-term PAB does not negatively affect the size of the PA vasculature.