Study of the mechanisms of arrhythmias in an anatomical computer model of human atria

Atrial fibrillation is the most frequent arrhythmia, provoking discomfort, heart failure and embolism. Based on a 20 heterogeneous and anisotropic model of cardiac tissue using the Beeler-Reuter and the Luo-Rudy models, a realistic 30 anatomical computer model of human atria containing about 250000 cardiac cells has been designed. The simulated size is 3 cm/spl times/3 cm/spl times/7 cm and holes of appropriate size have been placed for the veins and the valves. Using a programmed stimulation protocol similar to those of clinical electrophysiological studies, sustained atrial flutter with a periodic pattern has been induced as well as atrial fibrillation with a random pattern containing up to 6 independent wavelets. This virtual atrium can reproduce electrophysiological observations made in humans but with the advantage of showing details difficult to study in nature and of being reproducible.