Main Pulmonary Artery Dilatation after the Hybrid Procedure Exceeds Neo-aortic Dilatation after the Norwood/Sano Procedure: Is this a Cause for Concern?

  • Peter Pastuszko, Rady Children's Hospital of San Diego, San Diego, CA, United States
  • Howaida EL-Said, Rady Children's Hospital of San Diego, San Diego, CA, United States
  • John Moore, Rady Children's Hospital of San Diego, San Diego, CA, United States
  • Jolene Kriett, Rady Children's Hospital of San Diego, San Diego, CA, United States
  • Dana Connolly, Rady Children's Hospital of San Diego, San Diego, CA, United States
  • Dr John Lamberti, Rady Children's Hospital of San Diego, San Diego, CA, United States

    • Objectives: The Hybrid procedure (Bilateral PA Bands + PDA stent) is an alternative repair technique in Hypoplastic Left Heart Syndrome (HLHS). We have noted marked dilatation of the main pulmonary artery (MPA) after the Hybrid operation and postulate that the Hybrid procedure predisposes to greater MPA dilatation than the Norwood/Sano procedure.

    Methods: Between July 2007 and June 2008 six high-risk newborns underwent the Hybrid procedure. They were compared to twenty-one matched controls (Norwood/Sano). Echocardiographic data were reviewed, including the pulmonary valve annulus (PV) and z-score (PVz), the MPA and z-score (MPAz), and degree of pulmonary regurgitation (PR).

    Results: Mean age at procedure for all patients (N=27) was 10 days ± 8 and at follow-up was 4.5 months ± 1. Seventeen (63%) were female; 10 (37%) were male. In controls, there were significant increases in all diameters. Median increase in PV diameter was 3.2 mm ± 0.48 (p=001), PVz 0.64 ± 0.33 (p=0.009). MPA diameter increase was 2.6 ± 0.46 (p=0.001), MPAz 0.71 ± 0.29 (p=0.001). In the hybrid group, only the MPA diameter increased significantly, with a median increase of 4.7mm ± 1.43 (p=0.011). MPAz was 1.8 ± 1.09 (p=0.069). The change in PR was not significant in either group. There was a significant difference in MPA dilatation between Hybrids and controls (R2=0.85, p=0.009), not in other parameters.

    Conclusions: Dilatation of the MPA in short-term follow-up of Hybrids is concerning. It may be related to increased outflow impedance, altering timing and surgical strategy for stage II operation.