Dominik Siallagan1, Yue-Hin Loke2, Laura Olivieri3, Justin Opfermann4, Chin Siang Ong5, Diane de Zélicourt6, Anastasios Petrou7, Marianne Schmid Daners7, Vartan Kurtcuoglu6, Mirko Meboldt7, Kevin Nelson8, Luca Vricella5, Jed Johnson8, Narutoshi Hibino9, Axel Krieger10. 1. Sheikh Zayed Institute for Surgical Innovation, Children's National Medical Center, Washington, DC; Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland. 2. Division of Cardiology, Children's National Health System, Washington, DC. 3. Sheikh Zayed Institute for Surgical Innovation, Children's National Medical Center, Washington, DC; Division of Cardiology, Children's National Health System, Washington, DC. 4. Sheikh Zayed Institute for Surgical Innovation, Children's National Medical Center, Washington, DC. 5. Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, Md. 6. The Interface Group, Institute of Physiology, University of Zürich, Zurich, Switzerland; Swiss National Centre of Competence in Research, Kidney Control of Homeostasis, Zurich, Switzerland. 7. Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland. 8. Nanofiber Solutions, Inc, Hilliard, Ohio. 9. Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, Md. Electronic address: nhibino1@jhmi.edu. 10. Sheikh Zayed Institute for Surgical Innovation, Children's National Medical Center, Washington, DC; Department of Mechanical Engineering, University of Maryland, College Park, Md.
Abstract
BACKGROUND: Despite advances in the Fontan procedure, there is an unmet clinical need for patient-specific graft designs that are optimized for variations in patient anatomy. The objective of this study is to design and produce patient-specific Fontan geometries, with the goal of improving hepatic flow distribution (HFD) and reducing power loss (Ploss), and manufacturing these designs by electrospinning. METHODS: Cardiac magnetic resonance imaging data from patients who previously underwent a Fontan procedure (n = 2) was used to create 3-dimensional models of their native Fontan geometry using standard image segmentation and geometry reconstruction software. For each patient, alternative designs were explored in silico, including tube-shaped and bifurcated conduits, and their performance in terms of Ploss and HFD probed by computational fluid dynamic (CFD) simulations. The best-performing options were then fabricated using electrospinning. RESULTS: CFD simulations showed that the bifurcated conduit improved HFD between the left and right pulmonary arteries, whereas both types of conduits reduced Ploss. In vitro testing with a flow-loop chamber supported the CFD results. The proposed designs were then successfully electrospun into tissue-engineered vascular grafts. CONCLUSIONS: Our unique virtual cardiac surgery approach has the potential to improve the quality of surgery by manufacturing patient-specific designs before surgery, that are also optimized with balanced HFD and minimal Ploss, based on refinement of commercially available options for image segmentation, computer-aided design, and flow simulations.
BACKGROUND: Despite advances in the Fontan procedure, there is an unmet clinical need for patient-specific graft designs that are optimized for variations in patient anatomy. The objective of this study is to design and produce patient-specific Fontan geometries, with the goal of improving hepatic flow distribution (HFD) and reducing power loss (Ploss), and manufacturing these designs by electrospinning. METHODS: Cardiac magnetic resonance imaging data from patients who previously underwent a Fontan procedure (n = 2) was used to create 3-dimensional models of their native Fontan geometry using standard image segmentation and geometry reconstruction software. For each patient, alternative designs were explored in silico, including tube-shaped and bifurcated conduits, and their performance in terms of Ploss and HFD probed by computational fluid dynamic (CFD) simulations. The best-performing options were then fabricated using electrospinning. RESULTS:CFD simulations showed that the bifurcated conduit improved HFD between the left and right pulmonary arteries, whereas both types of conduits reduced Ploss. In vitro testing with a flow-loop chamber supported the CFD results. The proposed designs were then successfully electrospun into tissue-engineered vascular grafts. CONCLUSIONS: Our unique virtual cardiac surgery approach has the potential to improve the quality of surgery by manufacturing patient-specific designs before surgery, that are also optimized with balanced HFD and minimal Ploss, based on refinement of commercially available options for image segmentation, computer-aided design, and flow simulations.
Authors: Christopher M Haggerty; Kevin K Whitehead; James Bethel; Mark A Fogel; Ajit P Yoganathan Journal: Ann Thorac Surg Date: 2015-01-22 Impact factor: 4.330
Authors: Elaine Tang; Zhenglun Alan Wei; Kevin K Whitehead; Reza H Khiabani; Maria Restrepo; Lucia Mirabella; James Bethel; Stephen M Paridon; Bradley S Marino; Mark A Fogel; Ajit P Yoganathan Journal: Heart Date: 2017-05-18 Impact factor: 5.994