| A patient-specific right/left ventricle and patch
(RV/LV/Patch) combination model with fluid-structure interactions
(FSI) was introduced to evaluate and optimize human pulmonary valve
replacement/insertion (PVR) surgical procedure and patch design.
Cardiac Magnetic Resonance (CMR) imaging studies were performed to
acquire ventricle geometry, flow velocity and flow rate for healthy
volunteers and patients needing RV remodeling and PVR before and
after scheduled surgeries. CMR-based RV/LV/Patch FSI models were
constructed to perform mechanical analysis and provide accurate
assessment for RV mechanical conditions and cardiac function. These
models include a) fluid-structure interactions, b) isotropic and
anisotropic material properties, c) two-layer construction with
myocardial fiber orientation, and d) active contraction. Both pre-
and post-operation CMR data were used to adjust and validate the
model so that predicted RV volumes reached good agreement with CMR
measurements (error < 2%). Two RV/LV/Patch models were made based on
pre-operation data to evaluate and compare two PVR surgical
procedures: i) conventional patch with little or no scar tissue
trimming; ii) small patch with aggressive scar trimming and RV
volume reduction. Our modeling results indicated that: a)
patient-specific CMR-based computational modeling can provide
accurate assessment of RV cardiac functions; b) PVR with a smaller
patch and more aggressive scar removal led to reduced stress/strain
conditions in the patch area and may lead to improved recovery of RV
functions. More patient studies are needed to validate our findings.
This research was supported in part by NIH-R01-HL 089269 (del Nido,
Tang, Geva), NIH–R01-HL63095 (PI: del Nido, Harvard Medical School)
and NIH-NHLBI 5P50HL074734 (PI: Geva; Co-Investigator: del Nido,
Harvard Medical School). |