Fibrillation in a two-dimensional sheet of atrial myocardium: a computational study of wavefront-obstacle interactions

The goal of this simulation study is to examine the interaction of waves of fibrillation with centrally-located obstacles in a two-dimensional sheet of myocardium, thus providing information about the spatial organization of the wavefronts following obstacle creation. The authors used a monodomain model with modified Luo-Rudy I membrane kinetics to model the atrial myocardium. They considered three types of obstacles of equal area: a passive tissue obstacle, a conductive obstacle, and a non-conductive obstacle. For the obstacle dimensions tested, the authors found that interaction of only the passive obstacle with fibrillatory waves resulted in termination of fibrillation. They suggest that current returned to the active tissue from the conductive obstacle´s interior promotes wave fragmentation and continued fibrillation. Similarly, they believe current reflected by the non-conductive obstacle also helps sustain fibrillation