title: Can finite element models of ballooning procedures yield mechanical response of the cardiovascular site to overexpansion?
abstract: Patient-specific numerical models could aid the decision-making process for percutaneous valve selection; in order to be fully informative, they should include patient-specific data of both anatomy and mechanics of the implantation site. This information can be derived from routine clinical imaging during the cardiac cycle, but data on the implantation site mechanical response to device expansion are not routinely available. We aim to derive the implantation site response to overexpansion by monitoring pressure/dimensional changes during balloon sizing procedures and by applying a reverse engineering approach using a validated computational balloon model. This study presents the proof of concept for such computational framework tested in-vitro. A finite element (FE) model of a PTS-X405 sizing balloon (NuMed, Inc., USA) was created and validated against bench tests carried out on an ad hoc experimental apparatus: first on the balloon alone to replicate free expansion; second on the inflation of the balloon in a rapid prototyped cylinder with material deemed suitable for replicating pulmonary arteries in order to validate balloon/implantation site interaction algorithm. Finally, the balloon was inflated inside a compliant rapid prototyped patient-specific right ventricular outflow tract to test the validity of the approach. The corresponding FE simulation was set up to iteratively infer the mechanical response of the anatomical model. The test in this simplified condition confirmed the feasibility of the proposed approach and the potential for this methodology to provide patient-specific information on mechanical response of the implantation site when overexpanded, ultimately for more realistic computational simulations in patient-specific settings.
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK. Electronic address: giorgia.bosi.10@ucl.ac.uk.
authors.forename: Giorgia M
authors.initials: GM
authors.lastname: Bosi
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK; Department of Medical Physics & Biomedical Engineering, UCL, London, UK.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Biffi
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Biglino
authors.affiliation: Laboratory of Biological Structure Mechanics (LaBS), Chemistry, Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Lintas
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK.
authors.forename: Rod
authors.initials: R
authors.lastname: Jones
authors.affiliation: UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, UK.
authors.forename: Spyros
authors.initials: S
authors.lastname: Tzamtzis
authors.affiliation: UCL Mechanical Engineering, Cardiovascular Engineering Laboratory, University College London, UK.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Burriesci
authors.affiliation: Laboratory of Biological Structure Mechanics (LaBS), Chemistry, Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Migliavacca
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK.
authors.forename: Sachin
authors.initials: S
authors.lastname: Khambadkone
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Taylor
authors.affiliation: Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science & Great Ormond Street Hospital for Children, London, UK.
authors.forename: Silvia
authors.initials: S
authors.lastname: Schievano
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D020342:Finite Element Analysis; D006321:Heart / Q000502:physiology*; D006801:Humans; D008297:Male; D055595:Mechanical Phenomena; D019736:Prostheses and Implants
keywords: Finite element modelling; Implantation site mechanical response; Sizing balloons