Reentry anchoring at a pair of pulmonary vein ostia

Abstract

Recent findings in a sheep model of atrial fibrillation support the hypothesis that an organized micro-reentry could be the maintaining mechanism of the arrhythmia (mother wavelet). According to these studies we constructed a two dimensional computer model of tissue in the region around a pair of pulmonary vein ostia and investigated anchoring of a reentry wave at these ostia. We used the Luo Rudy phase I ionic current model to describe membrane kinetics and generated two different stages of electrical remodelling of the cells by varying the slow inward calcium current. Our attempt to initiate a stable reentry failed for cells with higher action potential duration and higher rate adaption. By simulating a higher stadium of electrical remodelling we finally were successful, and we were able to produce a periodic reentry. This led us to the conclusion that a low rate adaption (high electrical remodelling) facilitates organized activity in the atria. © Springer-Verlag Berlin Heidelberg 2005.