Transapical off-pump mitral valve repair with neochord implantation is an established technique for minimally-invasive intervention on mitral valve prolapse/flail. The procedure involves the positioning of artificial chords, whose length/tension is adjusted intraoperatively, adopting different methods based on the experience of the surgeon. This unsystematic approach occasionally leads to complications such as leaflet rupture and excessive/insufficient load on the neochords. In this study, finite element models of a generalized prolapsing mitral valve are used to verify the effect of two alternative tensioning approaches (AT – All together and 1-by-1 – one by one sequences) on the coaptation area and valve biomechanics, comparing results with a corresponding healthy configuration. The total force of about 1 N is exerted by the chords in both strategies, but the maximum stress and coaptation area are closer to those of the healthy configuration in the 1-by-1 sequence. However, the analysis also provides an explanation for the chords unloading in the 1-by-1 strategy observed in the clinical practice, and suggests an optimum tensioning methodology for NeoChord procedures. The study also reveals the potential power of the implemented numerical approach to serve as a tool for procedural planning, supporting the identification of the most suitable ventricular access site and the most effective stitching points for the artificial chords.

The neochord mitral valve repair procedure: Numerical simulation of different neochords tensioning protocols

Luigi Di Micco
;
Paolo Peruzzo;Andrea Colli;Daniela Boso;Laura Besola;Gino Gerosa;Francesca M. Susin
2019

Abstract

Transapical off-pump mitral valve repair with neochord implantation is an established technique for minimally-invasive intervention on mitral valve prolapse/flail. The procedure involves the positioning of artificial chords, whose length/tension is adjusted intraoperatively, adopting different methods based on the experience of the surgeon. This unsystematic approach occasionally leads to complications such as leaflet rupture and excessive/insufficient load on the neochords. In this study, finite element models of a generalized prolapsing mitral valve are used to verify the effect of two alternative tensioning approaches (AT – All together and 1-by-1 – one by one sequences) on the coaptation area and valve biomechanics, comparing results with a corresponding healthy configuration. The total force of about 1 N is exerted by the chords in both strategies, but the maximum stress and coaptation area are closer to those of the healthy configuration in the 1-by-1 sequence. However, the analysis also provides an explanation for the chords unloading in the 1-by-1 strategy observed in the clinical practice, and suggests an optimum tensioning methodology for NeoChord procedures. The study also reveals the potential power of the implemented numerical approach to serve as a tool for procedural planning, supporting the identification of the most suitable ventricular access site and the most effective stitching points for the artificial chords.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/3332189
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 5
  • ???jsp.display-item.citation.isi??? 4
social impact