Spontaneous termination of atrial fibrillation: study of the effect of atrial geometry in a biophysical model.

We studied the mechanisms of spontaneous termination of atrial fibrillation in a biophysical model of human atria, during the eight seconds preceding termination. The earliest detectable changes in the cycle length and the number of wavefronts occurred about three seconds prior to termination. We compared the mechanisms involved in the right and left atrium and investigated the effects of atrial geometry on the termination processes.

Optimization of antitachycardia pacing protocols applied to atrial fibrillation: insights from a biophysical model.

We present a model-based systematic study of antitachycardia pacing protocols applied to atrial fibrillation, focusing on the ability to achieve and maintain capture during pacing, as a function of both pacing site and period. We observed that pacing sites located away from anatomical obstacles led to faster and more robust capture. Moreover, after comparing burst and ramp pacing, our results indicate that in order to get capture it is necessary to pace at a fixed optimal period over a sufficient long time.