Summary
Objectives:
Using computer models for the study of complex atrial arrhythmias such as atrial
fibrillation is computationally demanding as long observation periods in the order
of tens of seconds are required. A well established approach for reducing computational
workload is to approximate the thin atrial walls by curved monolayers. On the other
hand, the finite element method (FEM) is a well established approach to solve the
underlying partial differential equations.
Methods:
A generalized 2D finite element method (FEM) is presented which computes the corresponding
stiffness and coupling matrix for arbitrarily shaped monolayers (ML). Compared to
standard 2D FEM, only one additional coordinate transformation is required. This allows
the use of existing FEM software with minor modifications. The algorithm was tested
to simulate wave propagation in benchmark geometries and in a model of atrial anatomy.
Results:
The ML model was able to simulate electric activation in curved tissue with anisotropic
conductivity. Simulations in branching tissue yielded slightly different patterns
when compared to a volumetric model with finite thickness. In the model of atrial
anatomy the computed activation times for five different pacing protocols displayed
a correlation of 0.88 compared to clinical data.
Conclusions:
The presented method provides a useful and easily implemented approach to model wave
propagation in MLs with a few restrictions to volumetric models.
Keywords
Computer model - monolayer - finite element method - atria
