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Can pulmonary conduit dysfunction and failure be reduced in infants and children less than age 2 years at initial
Tara Karamlou1, Eugene H Blackstone, John A Hawkins
1Division of Cardiovascular Surgery and Cardiology, Hospital for Sick Children, Toronto, Ontario, Canada.
Insights
Optimizing pulmonary conduit Z-scores between +1 and +3 can improve long-term function and reduce failure in infants. This study identified key risk factors for conduit intervention and explantation in young children.
Area of Science:
- Pediatric cardiology
- Congenital heart disease surgery
- Biomaterials in cardiovascular implants
Background:
- Pulmonary conduit failure is a significant concern in infants undergoing surgical repair of congenital heart defects.
- Understanding risk factors for pulmonary conduit dysfunction is crucial for improving patient outcomes.
Purpose of the Study:
- To identify risk factors associated with pulmonary conduit failure or dysfunction in infants under 2 years old.
- To evaluate the long-term durability and hemodynamic performance of various pulmonary conduit types.
Main Methods:
- A multi-institutional study analyzed data from 241 children discharged alive after initial pulmonary conduit insertion (2002-2005).
- Parametric hazard analysis and mixed regression models were used to assess time-related prevalence and risk factors for intervention/explantation and hemodynamic changes.
- Conduit types included pulmonary allografts, aortic allografts, bovine jugular venous valved conduits, porcine heterografts, and decellularized allografts.
Main Results:
- 58% of patients required intervention within 3 years; 30% underwent explantation.
- Smaller conduit Z-scores, younger age at implant, and pulmonary arborization abnormalities/stenoses were risk factors for intervention and explantation.
- Peak gradient and regurgitation progressed nonlinearly; faster progression was observed with aortic allografts and Z-scores outside the +1 to +3 range.
Conclusions:
- Pulmonary conduit durability and hemodynamic function can be enhanced in young patients by selecting conduits with Z-scores between +1 and +3.
- Optimizing conduit size and type is essential for minimizing reinterventions and improving long-term outcomes in pediatric cardiovascular surgery.
Objectives:
We sought to examine risk factors for pulmonary conduit failure or dysfunction in infants less than age 2 years at initial implantation.
Methods:
From 2002 to 2005, 241 children at 17 institutions were discharged alive after initial pulmonary conduit insertion. Initial conduit type was pulmonary allograft in 37%, aortic allograft in 29%, bovine jugular venous valved conduit in 25%, porcine heterograft in 2%, and decellularized allograft in 7%. Parametric hazard analysis determined time-related prevalence and associated risk factors for pulmonary conduit intervention and explantation. Serial echocardiographic measurements after conduit implant were analyzed by mixed regression models.
Results:
There were 89 first conduit-related interventions after discharge and 37 initial conduit explants were performed. First conduit intervention occurred at a constant rate, with a prevalence of 58% at 3 years from initial implant. Pulmonary conduit explantation (30% at 3 years) was characterized by an early-rising risk, suggesting that catheter-based intervention effectively blunts this early initial risk. Common risk-factors for first conduit intervention and explantation were smaller conduit Z-score and younger age at initial conduit implant, and the presence of pulmonary arborization abnormalities or stenoses. Pulmonary conduit peak gradient and regurgitation progressed nonlinearly in all patients over time. Gradient progressed more rapidly in children with aortic allografts and when initial conduit Z-score was less than +1 or more than +3. Pulmonary conduit regurgitation also progressed more rapidly in children with initial conduit Z-score greater than +3 and in those without jugular venous valved conduits, especially aortic allografts.
Conclusions:
Pulmonary conduit durability and hemodynamic function in patients undergoing initial conduit insertion at less than age 2 years can be improved by using pulmonary conduits with Z-scores between +1 and +3.
