Pulmonary Artery Interventions Following The Norwood Procedure
Zachary Spigel, Alyssa Thomason, Ziyad Binsalamah, Christopher Caldarone, Michiaki Imamura, Iki Adachi, Jeffrey Heinle, E Dean McKenzie.
Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA.
Evaluation of post-Norwood pulmonary artery interventions has focused on the percent of patients requiring intervention. We compared the mean number of interventions per patient (mean cumulative rate, MCR), which may be of greater importance to patients and families.
Pulmonary artery interventions (surgical or catheter-based) were evaluated at a single institution from 2011-208 and within the Single Ventricle Reconstruction trial public use datasets, two non-overlapping datasets. We compared the number of pulmonary artery interventions between patients with modified Blalock-Taussig Shunts (MBTS) and right ventricle to pulmonary artery conduits (RVPA). The MCR (mean number of pulmonary artery interventions per patient over time) were compared using the Nelson-Aalen estimator.
The Norwood procedure was performed on 117 patients (59 MBTS, 58 RVPA) at our institution. A total of 75 patients had a pulmonary artery intervention, including 33/58 (57%) after MBTS and 42/59 (71%) after RVPA (p=0.11). The MCR did not vary between cohorts (p=0.56, Figure A). Of the 549 patients in the SVR, 140 required pulmonary artery intervention, including 55 (21%) after MBTS and 85 (30%) after RVPA (p=0.0090). The MCR did not vary between SVR cohorts (p=0.26, Figure B).
Although more patients with RVPA than MBTS require pulmonary artery interventions after the Norwood procedure, the MCR are not different. The risk of pulmonary artery intervention should not dictate shunt choice during the Norwood procedure.