Mathematical model of geometry and fibrous structure of the heart.

摘要: We developed a mathematical representation of ventricular geometry and muscle fiber organization using three-dimensional finite elements referred to prolate spheroid coordinate system. Within elements, fields are approximated basis functions with associated parameters defined at the element nodes. Four per node used describe geometry. The radial is interpolated cubic Hermite that preserve slope continuity, while angular coordinates linearly. Two further nodal orientation myocardial fibers. fibers within planes bounded by epicardial endocardial surfaces linearly, transmural variation given functions. Left right orientations were characterized for canine heart arrested in diastole fixed zero pressure. was represented 24-element ensemble 41 Nodal fitted least squares provided realistic description [root mean square (RMS) error less than 0.9 mm] (RMS 2.6 mm) surfaces. Measured also 17 degrees) 60-element, 99-node mesh obtained subdividing mesh. These methods provide compact accurate anatomic ventricles suitable use stress analysis, simulation cardiac electrical activation, other field modeling problems.