Patient-specific virtual surgery for right ventricle volume reduction and patch design using MRI-based 3D FSI RV/LV/patch models

Right ventricular (RV) dysfunction is a common cause of heart failure in patients with congenital heart defects and often leads to impaired functional capacity and premature death. A novel surgical/modeling procedure is proposed to test the hypotheses that a) patient-specific image-based computational modeling can provide accurate information for assessment of RV function and that b) more aggressive scar removal using computer-aided surgery design with optimized post-operative RV morphology and patch design will lead to improved recovery of RV functions. Cardiac Magnetic Resonance (CMR) Imaging studies were performed in a dedicated MRI suite located in the Department of Cardiology at Children's Hospital Boston to acquire patient-specific ventricle geometry, heart motion, flow velocity, and flow rate for patients needing RV remodeling and pulmonary valve replacement operations before and after scheduled surgeries and healthy volunteers. MRI-based RV/LV combination models with fluid-structure interaction (FSI), RV-LV interaction, and RV-patch interaction were introduced to perform mechanical analysis and assess RV cardiac functions. The patient-specific FSI model (validated by pre-operation data) was used to predict possible outcome of virtual surgeries (i.e., with modified RV morphologies) and good agreement between computational predictions and pre-post operation RV stroke volume and ejection ratio as measured by CMR was found.