62 | Chapter 4 Conventional 2-, 3-, and 4-chamber views, as well as an RV-focused apical 4-chamber view, were used to visualize the RV lateral free wall (RVfw), interventricular septum (IVS), and LV free wall (LVfw). Cineloops were stored for offline two-dimensional speckle tracking using EchoPAC v. 202 (GE Vingmed Ultrasound, Horten, Norway). A single observer, blinded to clinical information, obtained segmental longitudinal strain curves of the RVfw and the LV. In this study, we focused on regional heterogeneity of RVfw tissue abnormalities because the RVfw is the most affected area in pathogenic desmosomal mutation carriers.10 Therefore, three segmental deformation patterns of the RVfw (i.e. apical, mid-ventricular and basal) were used to personalize the computational model (Figure 1). Additionally, two global deformation patterns of the LVfw and IVS were used to ensure realistic mechanical boundary conditions for the RVfw in terms of ventricular interaction. Global LVfw and IVS deformation patterns were obtained by averaging the 12 LVfw and 6 IVS segmental deformation curves, respectively, using the standardized 18-segment model.11 Figure 1. Methodology Right ventricular (RV), interventricular septal (IVS), and left ventricular (LV) strain were obtained using speckletracking echocardiography, and cardiac output was obtained using cardiovascular magnetic resonance imaging (CMR). Using a fully automatic estimation protocol, virtual subjects reproducing the clinical measures were generated and local tissue properties were extracted. Cardiac magnetic resonance imaging (CMR) was performed on a 1.5-T scanner (Achieva, Philips Healthcare, Best, the Netherlands), according to standard AC protocol12, and included measurements of the RV end-diastolic volume, RV ejection fraction, and LV ejection fraction. LV stroke volume was used to personalize cardiac output (CO) in the computer simulations. For further analysis, RV disease substrates were categorized by three different non-invasive imaging approaches, which have been published previously:
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