Tobon C, Ruiz C, Rodriguez J F, Hornero F, Ferrero J M, Saiz J
Universidad Politécnica de Valencia, (I3BH), Valencia, 46022 Spain.
Annu Int Conf IEEE Eng Med Biol Soc. 2010;2010:224-7. doi: 10.1109/IEMBS.2010.5627810.
Atrial tachycardias are the most common cardiac arrhythmias in clinical practice, which induce changes in atrial properties that help to perpetuate them. These changes are called "atrial remodeling". Recent studies have shown that rapid ectopic activity principally on the pulmonary veins can trigger reentrant mechanisms and lead to atrial tachycardias. However, the influences of ectopic foci location, the number of ectopic beats and its frequency on the likelihood of triggering reentries are not well known. In this work the effects of electrical remodeling were incorporated in an atrial cell model and integrated in a three-dimensional model of human atria, to develop a study of vulnerability for reentries. To carry out the study, an ectopic beat and a burst of six ectopic beats at two different frequencies were applied in six different locations in the atria. The results show greater vulnerability in the left pulmonary veins when we applied a single ectopic beat. When we increase the number of ectopic beats to six, a greater width of the vulnerable window was observed when ectopic focus frequency was high. The location, the number of ectopic beats and their frequency affect the vulnerability for reentry.
房性心动过速是临床实践中最常见的心律失常，它会引起心房特性的改变，而这些改变有助于使其持续存在。这些改变被称为“心房重构”。最近的研究表明，主要起源于肺静脉的快速异位活动可触发折返机制并导致房性心动过速。然而，异位灶位置、异位搏动数量及其频率对触发折返可能性的影响尚不清楚。在这项研究中，电重构的影响被纳入心房细胞模型，并整合到人体心房的三维模型中，以开展折返易感性的研究。为进行该研究，在心房的六个不同位置施加单个异位搏动以及以两种不同频率发放的六个异位搏动的短阵刺激。结果显示，当施加单个异位搏动时，左肺静脉的易感性更高。当我们将异位搏动数量增加到六个时，在异位灶频率较高时观察到更宽的易损窗。异位灶的位置、异位搏动数量及其频率会影响折返的易感性。
