Designing and 3D Printing Improved Patches for Patients Undergoing Surgical Repair of Congenital Heart Disease

Abstract

Introduction: Congenital heart disease (CHD) is deemed to have the highest cause of mortality amongst infants. In order to treat conditions such as hypoplastic blood vessels, a surgical patch may be required. Patch design may significantly influence defect repair, including haemodynamics. Imaging-based techniques such as 3D printing and computational simulations can foster advancement of research in innovative surgical patching.
Aims: To create a framework for designing and manufacturing custom-made surgical aortic patches for CHD patients using statistical shape modelling (SSM), computational fluid dynamics (CFD), and 3D bioprinting.
Methods: Data from cross-sectional imaging were reconstructed as aortic 3D models. SSM was used to generate a mean shape of the population. SSM and hierarchical clustering were assessed for robustness. Then SSM was used to investigate and compare patched aortas versus non-patched aortas. CFD was used to evaluate the haemodynamic implications in patched aortas. Optimisation was carried out for printing parameters to 3D print different aortic patch designs using GelXA bioink. The stiffness of the printable patches was measured. Ultimately, the feasibility of printing a personalised curved patch was tested.
Results: Computational techniques such as SSM and unsupervised clustering can provide insights into cardiovascular morphologies, relating to clinical characteristics and outcomes. Patched aortas following patch augmentation were larger than controls, with lower surface-to-volume ratio. CFD results revealed lower wall shear stress and greater power loss over time in patched aortas compared to controls. A range of patches with different designs was successfully 3D-bioprinted. Patches made out of GelXA had very low stiffness, whilst those made of both GelXA and polycaprolactone (PCL) had higher stiffness. Increasing the PCL printing speed and reducing the infill density exhibited mechanical properties within the range of native aortic tissue.
Conclusion: The feasibility of evaluating aortic morphology before and after different aortic valve surgeries using SSM and hierarchical clustering was demonstrated. Morphological changes over time were studied in patients with hypoplastic left heart syndrome (HLHS), including their haemodynamic implications. The curved patch which was designed from an SSM-derived mean aorta of the HLHS infants’ population was successfully 3D-bioprinted, demonstrating the feasibility of creating personalised patches using quantitative tools.

Date of Award	20 Jan 2026
Original language	English
Awarding Institution	University of Bristol
Sponsors	Kuwait Cultural Office
Supervisor	Giovanni Biglino (Supervisor)