title: Stress-shielding, growth and remodeling of pulmonary artery reinforced with copolymer scaffold and transposed into aortic position.
abstract: Ross operation, i.e., the use of autologous pulmonary artery to replace diseased aortic valve, has been recently at the center of a vivid debate regarding its unjust underuse in the surgical practice. Keystone of the procedure regards the use of an autologous biologically available graft which would preserve the anticoagulative and tissue homeostatic functions normally exerted by the native leaflets and would harmoniously integrate in the vascular system, allowing for progressive somatic growth of aortic structures. With this respect, recently, some of the authors have successfully pioneered a large animal model of transposition of pulmonary artery in systemic pressure load in order to reproduce the clinical scenario in which this procedure might be applied and allow for the development and testing of different devices or techniques to improve the pulmonary autograft (PA) performance, by testing a bioresorbable mesh for PA reinforcement. In the present work, to support and supplement the in vivo animal experimentation, a mathematical model is developed in order to simulate the biomechanical changes in pulmonary artery subjected to systemic pressure load and reinforced with a combination of resorbable and auxetic synthetic materials. The positive biological effects on vessel wall remodeling, the regional somatic growth phenomena and prevention of dilatative degeneration have been analyzed. The theoretical outcomes show that a virtuous biomechanical cooperation between biological and synthetic materials takes place, stress-shielding guiding the physiological arterialization of vessel walls, consequently determining the overall success of the autograft system.
authors.affiliation: Centre Cardiologique du Nord de Saint-Denis, Paris, France.
authors.forename: Francesco
authors.initials: F
authors.lastname: Nappi
authors.affiliation: Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples, Italy.
authors.forename: Angelo Rosario
authors.initials: AR
authors.lastname: Carotenuto
authors.affiliation: Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples, Italy.|Leibniz-Institut für Polymerforschung, Dresden, Germany.
authors.forename: Donato
authors.initials: D
authors.lastname: Di Vito
authors.affiliation: Department of Cardiothoracic Surgery, Golden Jubilee National Hospital, Clydebank, Glasgow, UK.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Spadaccio
authors.affiliation: Department of Cardiovascular Surgery, Hopital de la Salpetriere, Paris, France.
authors.forename: Cristophe
authors.initials: C
authors.lastname: Acar
authors.affiliation: Department of Structures for Engineering and Architecture, University of Napoli Federico II, Naples, Italy. fraldi@unina.it.|Interdisciplinary Research Center for Biomaterials, University of Napoli Federico II, Naples, Italy. fraldi@unina.it.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Fraldi
mesh_terms: D000792:Angiography; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000502:physiology*; D001696:Biomechanical Phenomena; D055119:Elastic Modulus; D011108:Polymers / Q000494:pharmacology*; D011651:Pulmonary Artery / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology*; D012756:Sheep; D013314:Stress, Mechanical; D054457:Tissue Scaffolds / Q000737:chemistry*; D066253:Vascular Remodeling
chemical_list: D011108:Polymers
keywords: Arterial walls; Auxetic materials; Growth; PDS scaffold; Pulmonary autograft; Remodeling; Ross procedure