title: Influence of left ventricular lead position relative to scar location on response to cardiac resynchronization therapy: a model study.
abstract: OBJECTIVE
  It is unclear how the position of the left ventricular (LV) lead relative to a scar affects the haemodynamic response in patients with dyssynchronous heart failure receiving cardiac resynchronization therapy. We investigated this complex interaction using a computational model.
  
  
  RESULTS
  The CircAdapt computational cardiovascular system model was used to simulate heart failure with left bundle branch block (LBBB). Myocardial scar was induced in four different regions of the LV free wall (LVFW). We then simulated biventricular pacing (BVP) in each heart, in which LV lead position was varied. The LV lead position leading to maximal acute change in LV stroke volume (SV) was defined as optimal lead position. In LBBB without scar, SV increase was maximal when pacing the LVFW region most distant from the septum. With a scar adjacent to the septum, maximal response was achieved when pacing remote from both the septum and the scar. When the scar was located further from the septum, the BVP-induced increase of SV was small. For all hearts, pacing from the optimal LV lead position resulted in the most homogeneous distribution of local ventricular myofibre work and the largest increase in summed left and right ventricular pump work.
  
  
  CONCLUSIONS
  These computer simulations suggest that, in hearts with LBBB and scar, the optimal LV lead position is a compromise between a position distant from the scar and from the septum. In infarcted hearts, the best haemodynamic effect is achieved when electromechanical resynchronization of the remaining viable myocardium is most effective.
authors.affiliation: Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Universiteitssingel 50, P.O. Box 616, 6229 ER Maastricht, The Netherlands.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Huntjens
authors.affiliation: Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Universiteitssingel 50, P.O. Box 616, 6229 ER Maastricht, The Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Walmsley
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, IHU LIRYC, CHU de Bordeaux, Bordeaux, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Ploux
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, IHU LIRYC, CHU de Bordeaux, Bordeaux, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Bordachar
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands.
authors.forename: Frits W
authors.initials: FW
authors.lastname: Prinzen
authors.affiliation: Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Universiteitssingel 50, P.O. Box 616, 6229 ER Maastricht, The Netherlands.
authors.forename: Tammo
authors.initials: T
authors.lastname: Delhaas
authors.affiliation: Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Universiteitssingel 50, P.O. Box 616, 6229 ER Maastricht, The Netherlands Hôpital Cardiologique du Haut-Lévêque, IHU LIRYC, CHU de Bordeaux, Bordeaux, France joost.lumens@maastrichtuniversity.nl.
authors.forename: Joost
authors.initials: J
authors.lastname: Lumens
mesh_terms: D002037:Bundle-Branch Block / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy; D058409:Cardiac Resynchronization Therapy Devices; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology*; D003198:Computer Simulation; D004867:Equipment Design; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D008955:Models, Cardiovascular; D009206:Myocardium / Q000473:pathology*; D013318:Stroke Volume; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right; D017725:Ventricular Pressure
keywords: Biventricular pacing; Computer model; Haemodynamics; Heart failure; Optimization