Simulation Of Normal Electrophysilogy And Atrial Fibrillation With Vitrual Heart Model

Virtual heart modeling and simulation is the simulation of cardiac structure and function, virtual heart modeling can help improve the diagnosis and treatment of heart disease, and innovative drug development. This paper first introduces the history of the mathematical modeling of cardiac anatomy and the importance of heart simulation, and then focus on the procedures and methods of using the software ScanIP to CT image segmentation and reconstruction, and finally quantitative analysis of the reconstructed mathematical model, and compares with the clinical results. For complete modeling of the heart conduction system, so far there have not been amodel which is fully based on images, owing to the resolution, we use the Mimics software and combine with published anatomical knowledge of cardiac conduction system to establish a complete virtual heart conduction systemfor the first time, which includes a sinus node, crista terminalis, right atrial pectinate muscles, Bachmann bundle, left atrial pectinate muscles, pulmonary vein, fossa ovalis, coronary sinus, atrioventricular node, slow pathway, rapid pathway, superior vena cava, inferior vena cava, fibrous ring, atrioventricular bundle, left bundle HIS, right HIS bundle, left Purkinje fiber network, rightPurkinje fiber network. The data provides a good platform for the subsequent heart cardiac electrophysiology and mechanics simulation.Fiber rotation plays a big impact on the accuracy of the simulation results in the heart simulation, so in this paper myofilament separation method was used to obtain the endocardial and epicardial fiber rotation, and then the linear interpolation method was used to calculate the ventricular transmural fiber rotation, meanwhile, the shortest path method was used to calculate the atrium fiber rotation, these data provides a good simulation platform for future cardiac electrophysiology and mechanics simulation.Iffinite element method is used to simulate the cardiac electrophysiological and mechanical characters, then the first thing is to mesh the heart.Mesh generation is the precondition of finite element analysis, the quality of the mesh determines the precision of the computation results, those low-quality meshes might lead to incorrect results, and thus it is necessary to produce high-quality meshes for finite element analysis. Most commercial software generates meshes on the basis of the entity of an object, while seldom uses the discrete point data to produce meshes directly. Furthermore, the compatibility problem among different softwares always slows down the progress of research. This paper aims at producing Constrained Delaunay Tetrahedral meshes for heart anatomy model with Visual C++language.The anatomical model coupled with the action potential model can be used to carried out simulation of cardiac electrophysiology, our laboratory constructed34different cell models, and then used the monodomain model to simulate the spread of cardiac electricity, and finally the parallel simulation was used to simulate the excitation conduction. To further study the electrophysiological properties of the heart, we simulated the atrial electrical conduction under sinus rhythm, in this process, we assume that there are two bundles connectes the terminal crest and oval fossaand coronary sinus, and then we compared the simualation results with experimtant data, and our hypothesis was validated.Finally, we also carried out the pathological heart simulation, especially atrial fibrillation study. Our simulation results show that the heterogeneity of action potential in the right atrium made the wave front in the right atrium prone to fragmentation which caused atrial fibrillation. In addition our simulation also found that fiber orientation was important in induce and maintenance atrial fibrillation.