High-Risk Hypoplastic Left Heart Syndrome or Complex: Midterm Survival after Initial Bilateral Pulmonary Artery Banding Followed by Early Norwood Procedure

Objectives: We report our experience with initial bilateral pulmonary artery banding (PAB) and postponing the Norwood procedure (NP) for high risk neonates.

Methods: Retrospective study of patients admitted with hypoplastic left ventricle, between July 2012 and February 2017, with diagnoses or clinical status prohibiting neonatal NP.

Results: Overall, 17 patients (12 HLHS, 5 variants) underwent PAB at a median age of 8 days (range: 1–108 days) with a median weight of 3,150 g (range: 1,600–3,840 g). Complexity displayed by the mean Comprehensive Aristotle Score for NP was 19.3 ± 2.2. Risk factors included prematurity (n = 4), weight ≤2.5 kg (n = 7), aortic atresia (n = 7), highly restrictive atrial septum (n = 9), total anomalous pulmonary venous connection (TAPVC) (n = 3), mechanical ventilation (n = 3), shock with renal failure (n = 1). Four patients had a score > 20. In 47% additional procedures required cardio-pulmonary-bypass at PAB mostly for resection of the interatrial septum in seven and TAPVC repair in two cases. Patency of ductus arteriosus was maintained with prostaglandin and secondary stenting was necessary in three cases. Survival after PAB was 82.4%. Fourteen patients subsequently underwent successful NP with a median age of 56 days (range: 13–616 days) and median weight of 3,630 g (range: 2,500–8,690 g). All patients survived NP. Median ventilation time was 13 days (range: 1–38 days) and median ICU stay 19 days (range: 3–54 days). There was one interstage death at home 99 days after NP. Pre-Glenn mean lower lobe index was 188 ± 132 mm²/m², mean PA pressure 17 ± 2.9 mm Hg and mean EDP 10.7 ± 2.4 mm Hg. Bidirectional cavopulmonary connection was performed in 13 patients with 92.3% survival followed by total cavopulmonary connection (100% survival) in three. Therefore, midterm survival after palliation with initial PAB is 70.6% with a mean follow-up time of 2.5 ± 1.5 years after PAB.

Conclusion: Initial PAB followed by interstage Norwood for high-risk neonates reduced Norwood mortality considerably in this cohort and was associated with a midterm survival comparable to low risk neonates with HLHS.