title: Mathematical multi-scale model of the cardiovascular system including mitral valve dynamics. Application to ischemic mitral insufficiency.
abstract: BACKGROUND
  Valve dysfunction is a common cardiovascular pathology. Despite significant clinical research, there is little formal study of how valve dysfunction affects overall circulatory dynamics. Validated models would offer the ability to better understand these dynamics and thus optimize diagnosis, as well as surgical and other interventions.
  
  
  METHODS
  A cardiovascular and circulatory system (CVS) model has already been validated in silico, and in several animal model studies. It accounts for valve dynamics using Heaviside functions to simulate a physiologically accurate "open on pressure, close on flow" law. However, it does not consider real-time valve opening dynamics and therefore does not fully capture valve dysfunction, particularly where the dysfunction involves partial closure. This research describes an updated version of this previous closed-loop CVS model that includes the progressive opening of the mitral valve, and is defined over the full cardiac cycle.
  
  
  RESULTS
  Simulations of the cardiovascular system with healthy mitral valve are performed, and, the global hemodynamic behaviour is studied compared with previously validated results. The error between resulting pressure-volume (PV) loops of already validated CVS model and the new CVS model that includes the progressive opening of the mitral valve is assessed and remains within typical measurement error and variability. Simulations of ischemic mitral insufficiency are also performed. Pressure-Volume loops, transmitral flow evolution and mitral valve aperture area evolution follow reported measurements in shape, amplitude and trends.
  
  
  CONCLUSIONS
  The resulting cardiovascular system model including mitral valve dynamics provides a foundation for clinical validation and the study of valvular dysfunction in vivo. The overall models and results could readily be generalised to other cardiac valves.
authors.affiliation: Cardiovascular Research Center, University of Liege, Liege, Belgium. sabine.paeme@ulg.ac.be
authors.forename: Sabine
authors.initials: S
authors.lastname: Paeme
authors.forename: Katherine T
authors.initials: KT
authors.lastname: Moorhead
authors.forename: J Geoffrey
authors.initials: JG
authors.lastname: Chase
authors.forename: Bernard
authors.initials: B
authors.lastname: Lambermont
authors.forename: Philippe
authors.initials: P
authors.lastname: Kolh
authors.forename: Vincent
authors.initials: V
authors.lastname: D'orio
authors.forename: Luc
authors.initials: L
authors.lastname: Pierard
authors.forename: Marie
authors.initials: M
authors.lastname: Moonen
authors.forename: Patrizio
authors.initials: P
authors.lastname: Lancellotti
authors.forename: Pierre C
authors.initials: PC
authors.lastname: Dauby
authors.forename: Thomas
authors.initials: T
authors.lastname: Desaive
mesh_terms: D002319:Cardiovascular System; D006439:Hemodynamics; D006801:Humans; D008943:Mitral Valve / Q000502:physiology*; D008944:Mitral Valve Insufficiency; D008955:Models, Cardiovascular