Caili Li^1,§, Christopher Baird², Jing Yao³, Chun Yang⁴, Liang Wang⁵, Han Yu⁵, Tal Geva⁶, Dalin Tang^5,*,7,§

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 59-59, 2019, DOI:10.32604/mcb.2019.06872

Abstract Pulmonary valve stenosis (PVS) is one common right ventricular outflow tract obstruction problem in patients with tetralogy of Fallot (TOF). Congenital bicuspid pulmonary valve (BPV) is a condition of valvular stenosis, and the occurrence of congenital BPV is often associated with TOF. Dynamic computational models of normal pulmonary root (PR) with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions. The pulmonary root geometry included valvular leaflets, sinuses, interleaflet triangles and annulus. Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing… More >

Caili Li¹, Jing Yao², Chun Yang³, Di Xu², Liang Wang⁴, Dalin Tang^4,5,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 77-78, 2019, DOI:10.32604/mcb.2019.05745

Abstract Pulmonary valve stenosis (PVS) is one common post-operative problem in patients with tetralogy of Fallot (TOF) after repair. Congenital bicuspid pulmonary valve (BPV) is a condition of valvular stenosis, and the occurrence of congenital BPV is often associated with TOF. Compared with the biomechanical simulation model of the bicuspid aortic valve, the BPV is often neglected. In this study, we developed a dynamic biomechanical model of a simulated normal pulmonary root (PR) with tri-leaflet and a model of simulated PR with BPV in patients with repaired TOF in order to describe the effect of geometric structure with BPV on the… More >

Han Yu¹, Pedro J. del Nido², Tal Geva³, Chun Yang⁴, Zheyang Wu⁴, Rahul H. Rathod³, Xueying Huang⁵, Kristen L. Billiar⁶, Dalin Tang^1,4,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 73-74, 2019, DOI:10.32604/mcb.2019.05837

Abstract Ventricle mechanical stress and strain calculations play an important role in cardiovascular investigations. Patients with repaired tetralogy of Fallot (TOF) account for the majority of cases with late onset right ventricular (RV) failure. The current surgical approach, including pulmonary valve replacement(PVR), has yielded mixed results with some patients recover RV function after pulmonary valve insertion with or without concomitant RV remodeling surgery but some do not[Therrien, Siu and McLaughlin (2000);]. Cardiac magnetic resonance (CMR) data were collected from 6 healthy volunteers and 12 Tetralogy of Fallot (TOF) patients before PVR with consent obtained. 12 patients were divided into two groups… More >

Caili Li^{1, §}, Christopher Baird², Jing Yao³, Chun Yang⁴, Liang Wang⁵, Han Yu⁵, Tal Geva⁶, Dalin Tang^{5*, 7, §}

CMES-Computer Modeling in Engineering & Sciences, Vol.119, No.1, pp. 227-244, 2019, DOI:10.32604/cmes.2019.06036

Abstract Pulmonary valve stenosis (PVS) is one common right ventricular outflow tract obstruction problem in patients with tetralogy of Fallot (TOF). Congenital bicuspid pulmonary valve (BPV) is a condition of valvular stenosis, and the occurrence of congenital BPV is often associated with TOF. Dynamic computational models of normal pulmonary root (PR) with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions. The pulmonary root geometry included valvular leaflets, sinuses, interleaflet triangles and annulus. Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing… More >

Zhedian Zhou¹, Tal Geva², Rahul H. Rathod², Alexander Tang², Chun Yang³, Kristen L. Billiar⁴, Dalin Tang^1,*,3, Pedro del Nido⁵

Molecular & Cellular Biomechanics, Vol.15, No.2, pp. 99-115, 2018, DOI: 10.3970/mcb.2018.00558

Abstract Patients with repaired Tetralogy of Fallot (ToF), a congenital heart defect which includes a ventricular septal defect and severe right ventricular outflow obstruction, account for the majority of cases with late onset right ventricle (RV) failure. The current surgical approach, which includes pulmonary valve replacement/insertion (PVR), has yielded mixed results. A computational parametric study using 7 patient-specific RV/LV models based on cardiac magnetic resonance (CMR) data as "virtual surgery" was performed to investigate the impact of patch size, RV remodeling and tissue regeneration in PVR surgery design on RV cardiac functions. Two patch sizes, three degrees of scar trimming (RV… More >

Dalin Tang^*, Chun Yang^†, Tal Geva^‡,§, Pedro J. del Nido^¶

Molecular & Cellular Biomechanics, Vol.4, No.3, pp. 159-176, 2007, DOI:10.3970/mcb.2007.004.159

Abstract A single-layer isotropic patient-specific right/left ventricle and patch (RV/LV/Patch) combination model with fluid-structure interactions (FSI) was introduced in our previous papers to evaluate and optimize human pulmonary valve replacement/insertion (PVR) surgical procedure and patch design. In this paper, an active anisotropic model with two-layer structure for ventricle wall and tissue fiber orientation was introduced to improve previous isotropic model for more accurate assessment of RV function and potential application in PVR surgery and patch design. A material-stiffening approach was used to model active heart contraction. The computational models were used to conduct ``virtual (computational)'' surgeries and test the hypothesis that… More >