Comparison of pulmonary arterial wall properties between a congenital heart disease patient and a normal subject using in vivo pressure-diameter measurements: A feasibility study

摘要

Patients with congenital heart disease (CHD) requiring pulmonary valve and right ventricular intervention often suffer from residual lesions including pulmonary regurgitation or pulmonary artery (PA) obstruction after the placement of a patch or artificial conduit during surgery. These residual lesions can result in significant changes in the structure and function of the right ventricle (RV) and PA. Characterization of the material properties such as stress, strain, and compliance of the PA provides a quantitative assessment of RV-PA dysfunction and may aid in the longitudinal assessment of CHD patients. Thus, in this feasibility study, we aim to assess the variations in the material properties between the left PA (LPA) of a CHD patient, which was located in close proximity of the RV-main PA (MPA) homograft, and that of a normal subject (control) with a native LPA, using in vivo pressure-diameter data as input to a non-linear material model.In vivo LPA pressure and diameter were obtained using cardiac catheterization and cardiac MRI, respectively. This in vivo data was used in conjunction with a set of sample constitutive equations to define a 2D nonlinear anisotropic material model for the LPA. Subsequently, the model constants were predicted using an optimization algorithm and by applying an equilibrium condition to the LPA wall. The model was then used to predict the pressure-diameter and stress-stretch characteristics of the LPA of the patient and control.