Modeling Right Ventricle Failure After Continuous Flow Left Ventricular Assist Device: A Biventricular Finite-Element and Lumped-Parameter Analysis

The risk of right ventricle (RV) failure remains amajor contraindication for continuous-flow left ventricularassist device (CF-LVAD) implantation in patients with heartfailure. It is therefore critical to identify the patients who willbenefit from early intervention to avoid adverse outcomes. Wesought to advance the computational modeling description ofthe mechanisms underlying RV failure in LVAD-supportedpatients. RV failure was studied by computational modelingof hemodynamic and cardiac mechanics using lumped-parameter and biventricular finite element (FE) analysis. Findingswere validated by comparison of bi-dimensional speckletracking echocardiographic strain assessment of the RV freewall vs. patient-specific computational strain estimations, andby non-invasive lumped-based hemodynamic predictions vs.invasive right heart catheterization data. Correlation analysisrevealed that lumped-derived RV cardiac output (R = 0.94)and RV stroke work index (R = 0.85) were in good agreement with catheterization data collected from 7 patients withCF-LVAD. Biventricular FE analysis showed abnormalmotion of the interventricular septum towards the leftventricular free wall, suggesting impaired right heart mechanics. Good agreement between computationally predicted andechocardiographic measured longitudinal strains was found atbasal ( 19.1 ± 3.0% for ECHO, and 16.4 ± 3.2% forFEM), apical ( 20.0 ± 3.7% for ECHO, and 17.4 ± 2.7% for FEM), and mid-level of the RV free wall( 20.1 ± 5.9% for echo, and 18.0 ± 5.4% for FEM).Simulation approach here presented could serve as a tool forless invasive and early diagnosis of the severity of RV failure inpatients with LVAD, although future studies are needed tovalidate our findings against clinical outcomes.