Peter E Hammer1, Erin G Roberts2, Sitaram M Emani3, Pedro J Del Nido3. 1. Department of Cardiac Surgery, Boston Children's Hospital, Boston, Mass. Electronic address: peter.hammer@childrens.harvard.edu. 2. Department of Cardiac Surgery, Boston Children's Hospital, Boston, Mass; Division of Materials Science and Engineering, Boston University, Boston, Mass. 3. Department of Cardiac Surgery, Boston Children's Hospital, Boston, Mass.
Abstract
OBJECTIVES: Neither heart valve repair methods nor current prostheses can accommodate patient growth. Normal aortic and pulmonary valves have 3 leaflets, and the goal of valve repair and replacement is typically to restore normal 3-leaflet morphology. However, mammalian venous valves have bileaflet morphology and open and close effectively over a wide range of vessel sizes. We propose that they might serve as a model for pediatric heart valve reconstruction and replacement valve design. We explore this concept using computer simulation. METHODS: We use a finite element method to simulate the ability of a reconstructed cardiac semilunar valve to close competently in a growing vessel, comparing a 3-leaflet design with a 2-leaflet design that mimics a venous valve. Three venous valve designs were simulated to begin to explore the parameter space. RESULTS: Simulations show that for an initial vessel diameter of 12 mm, the venous valve design remains competent as the vessel grows to 20 mm (67%), whereas the normal semilunar design remains competent only to 13 mm (8%). Simulations also suggested that systolic function, estimated as effective orifice area, was not detrimentally affected by the venous valve design, with all 3 venous valve designs exhibiting greater effective orifice area than the semilunar valve design at a given level of vessel growth. CONCLUSIONS: Morphologic features of the venous valve design make it well suited for competent closure over a wide range of vessel sizes, suggesting its use as a model for semilunar valve reconstruction in the growing child.
OBJECTIVES: Neither heart valve repair methods nor current prostheses can accommodate patient growth. Normal aortic and pulmonary valves have 3 leaflets, and the goal of valve repair and replacement is typically to restore normal 3-leaflet morphology. However, mammalian venous valves have bileaflet morphology and open and close effectively over a wide range of vessel sizes. We propose that they might serve as a model for pediatric heart valve reconstruction and replacement valve design. We explore this concept using computer simulation. METHODS: We use a finite element method to simulate the ability of a reconstructed cardiac semilunar valve to close competently in a growing vessel, comparing a 3-leaflet design with a 2-leaflet design that mimics a venous valve. Three venous valve designs were simulated to begin to explore the parameter space. RESULTS: Simulations show that for an initial vessel diameter of 12 mm, the venous valve design remains competent as the vessel grows to 20 mm (67%), whereas the normal semilunar design remains competent only to 13 mm (8%). Simulations also suggested that systolic function, estimated as effective orifice area, was not detrimentally affected by the venous valve design, with all 3 venous valve designs exhibiting greater effective orifice area than the semilunar valve design at a given level of vessel growth. CONCLUSIONS: Morphologic features of the venous valve design make it well suited for competent closure over a wide range of vessel sizes, suggesting its use as a model for semilunar valve reconstruction in the growing child.
Authors: Babar S Hasan; Doff B McElhinney; David W Brown; John P Cheatham; Julie A Vincent; William E Hellenbrand; Thomas K Jones; Evan M Zahn; James E Lock Journal: Circ Cardiovasc Interv Date: 2011-11-09 Impact factor: 6.546
Authors: Luis G Quiñonez; Roger Breitbart; Wayne Tworetsky; James E Lock; Audrey C Marshall; Sitaram M Emani Journal: J Thorac Cardiovasc Surg Date: 2013-12-10 Impact factor: 5.209
Authors: Sophie C Hofferberth; Mossab Y Saeed; Lara Tomholt; Matheus C Fernandes; Christopher J Payne; Karl Price; Gerald R Marx; Jesse J Esch; David W Brown; Jonathan Brown; Peter E Hammer; Richard W Bianco; James C Weaver; Elazer R Edelman; Pedro J Del Nido Journal: Sci Transl Med Date: 2020-02-19 Impact factor: 17.956