Eric L Pierce1, Charles H Bloodworth1, Andrew W Siefert2, Thomas F Easley1, Tetsushi Takayama3, Tomonori Kawamura3, Robert C Gorman3, Joseph H Gorman3, Ajit P Yoganathan4. 1. The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Ga. 2. The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Ga; Momentum PMV, Inc, Alpharetta, Ga. 3. Gorman Cardiovascular Research Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pa. 4. The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Ga. Electronic address: ajit.yoganathan@bme.gatech.edu.
Abstract
OBJECTIVE: The study objective was to quantify the effect of ring type, ring-annulus sizing, suture position, and surgeon on the forces required to tie down and constrain a mitral annuloplasty ring to a beating heart. METHODS: Physio (Edwards Lifesciences, Irvine, Calif) or Profile 3D (Medtronic, Dublin, Ireland) annuloplasty rings were instrumented with suture force transducers and implanted in ovine subjects (N = 23). Tie-down forces and cyclic contractile forces were recorded and analyzed at 10 suture positions and at 3 levels of increasing peak left ventricular pressure. RESULTS: Across all conditions, tie-down force was 2.7 ± 1.4 N and cyclic contractile force was 2.0 ± 1.2 N. Tie-down force was not meaningfully affected by any factor except surgeon. Significant differences in overall and individual tie-down forces were observed between the 2 primary implanting surgeons. No other factors were observed to significantly affect tie-down force. Contractile suture forces were significantly reduced by ring-annulus true sizing. This was driven almost exclusively by Physio cases and by reduction along the anterior aspect, where dehiscence is less common clinically. Contractile suture forces did not differ significantly between ring types. However, when undersizing, Profile 3D forces were significantly more uniform around the annular circumference. A suture's tie-down force did not correlate to its eventual contractile force. CONCLUSIONS: Mitral annuloplasty suture loading is influenced by ring type, ring-annulus sizing, suture position, and surgeon, suggesting that reports of dehiscence may not be merely a series of isolated errors. When compared with forces known to cause suture dehiscence, these in vivo suture loading data aid in establishing potential targets for reducing the occurrence of ring dehiscence.
OBJECTIVE: The study objective was to quantify the effect of ring type, ring-annulus sizing, suture position, and surgeon on the forces required to tie down and constrain a mitral annuloplasty ring to a beating heart. METHODS: Physio (Edwards Lifesciences, Irvine, Calif) or Profile 3D (Medtronic, Dublin, Ireland) annuloplasty rings were instrumented with suture force transducers and implanted in ovine subjects (N = 23). Tie-down forces and cyclic contractile forces were recorded and analyzed at 10 suture positions and at 3 levels of increasing peak left ventricular pressure. RESULTS: Across all conditions, tie-down force was 2.7 ± 1.4 N and cyclic contractile force was 2.0 ± 1.2 N. Tie-down force was not meaningfully affected by any factor except surgeon. Significant differences in overall and individual tie-down forces were observed between the 2 primary implanting surgeons. No other factors were observed to significantly affect tie-down force. Contractile suture forces were significantly reduced by ring-annulus true sizing. This was driven almost exclusively by Physio cases and by reduction along the anterior aspect, where dehiscence is less common clinically. Contractile suture forces did not differ significantly between ring types. However, when undersizing, Profile 3D forces were significantly more uniform around the annular circumference. A suture's tie-down force did not correlate to its eventual contractile force. CONCLUSIONS:Mitral annuloplasty suture loading is influenced by ring type, ring-annulus sizing, suture position, and surgeon, suggesting that reports of dehiscence may not be merely a series of isolated errors. When compared with forces known to cause suture dehiscence, these in vivo suture loading data aid in establishing potential targets for reducing the occurrence of ring dehiscence.
Authors: Beatrice E Ncho; Eric L Pierce; Charles H Bloodworth; Akito Imai; Keitaro Okamoto; Yoshiaki Saito; Robert C Gorman; Joseph H Gorman; Ajit P Yoganathan Journal: J Thorac Cardiovasc Surg Date: 2019-05-31 Impact factor: 5.209
Authors: Samuel Frishman; Ali Kight; Ileana Pirozzi; Sainiteesh Maddineni; Annabel M Imbrie-Moore; Zulekha Karachiwalla; Michael J Paulsen; Alexander D Kaiser; Y Joseph Woo; Mark R Cutkosky Journal: J Med Device Date: 2022-05-18 Impact factor: 0.743
Authors: Immanuel David Madukauwa-David; Eric L Pierce; Fatiesa Sulejmani; Joshua Pataky; Wei Sun; Ajit P Yoganathan Journal: Biomech Model Mechanobiol Date: 2018-10-04
Authors: Matthew H Park; Yuanjia Zhu; Annabel M Imbrie-Moore; Hanjay Wang; Mateo Marin-Cuartas; Michael J Paulsen; Y Joseph Woo Journal: Front Cardiovasc Med Date: 2021-07-08