Behaviour of the purkinje system during defibrillation-strength shocks. Export

@article{citeulike:4784055, abstract = {During normal sinus rhythm, orderly activation of the heart is facilitated by a specialized network of fibres lining the ventricles called the Purkinje system (PS). Characteristic features of the PS encourage coordinated depolarization of spatially disparate endocardial sites. Although the basic role of the PS is well understood, many questions regarding its behaviour, especially during the process of defibrillation, remain unanswered. Purkinje fibres react differently during large electrical shocks than the myocardium on which they run because they are oriented in different directions than the endocardial fibres, they possess distinct electrophysiology, and they are part of a system that is one-dimensional in nature. Because of the small size of Purkinje fibres and their positioning on the endocardium, in vivo observation of PS-related phenomena remains problematic. Therefore, computer modelling offers a unique opportunity to investigate the role of the PS during defibrillation. In this paper, the effects of defibrillation-strength shocks on a finite element model of the ventricles coupled to a distinct PS are ascertained. Results indicate that the presence of the PS has a profound impact on the course of activation in the ventricles. During shocks, depolarizations are elicited at bends and bifurcations in the PS. Subsequently, this activity spreads throughout the PS in all directions, creating numerous regions of myocardial depolarization and accelerating the excitation of the whole structure. These excitations are explained by the cable-like nature of Purkinje fibres, which exposes them to vastly different electrical field effects than bulk myocardium due to abrupt conductivity tensor changes.}, author = {Boyle, P. M. and Deo, M. and Vigmond, E. J.}, citeulike-article-id = {4784055}, citeulike-linkout-0 = {http://dx.doi.org/10.1109/IEMBS.2007.4352313}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/18001979}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=18001979}, doi = {10.1109/IEMBS.2007.4352313}, issn = {1557-170X}, journal = {Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference}, keywords = {natreview0609}, pages = {419--422}, posted-at = {2009-06-09 03:24:39}, priority = {2}, title = {Behaviour of the purkinje system during defibrillation-strength shocks.}, url = {http://dx.doi.org/10.1109/IEMBS.2007.4352313}, volume = {2007}, year = {2007} }

TY - JOUR ID - citeulike:4784055 L3 - citeulike-article-id:4784055 N2 - During normal sinus rhythm, orderly activation of the heart is facilitated by a specialized network of fibres lining the ventricles called the Purkinje system (PS). Characteristic features of the PS encourage coordinated depolarization of spatially disparate endocardial sites. Although the basic role of the PS is well understood, many questions regarding its behaviour, especially during the process of defibrillation, remain unanswered. Purkinje fibres react differently during large electrical shocks than the myocardium on which they run because they are oriented in different directions than the endocardial fibres, they possess distinct electrophysiology, and they are part of a system that is one-dimensional in nature. Because of the small size of Purkinje fibres and their positioning on the endocardium, in vivo observation of PS-related phenomena remains problematic. Therefore, computer modelling offers a unique opportunity to investigate the role of the PS during defibrillation. In this paper, the effects of defibrillation-strength shocks on a finite element model of the ventricles coupled to a distinct PS are ascertained. Results indicate that the presence of the PS has a profound impact on the course of activation in the ventricles. During shocks, depolarizations are elicited at bends and bifurcations in the PS. Subsequently, this activity spreads throughout the PS in all directions, creating numerous regions of myocardial depolarization and accelerating the excitation of the whole structure. These excitations are explained by the cable-like nature of Purkinje fibres, which exposes them to vastly different electrical field effects than bulk myocardium due to abrupt conductivity tensor changes. JF - Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference SN - 1557-170X EP - 422 TI - Behaviour of the purkinje system during defibrillation-strength shocks. VL - 2007 SP - 419 KW - natreview0609 AU - Boyle, PM AU - Deo, M AU - Vigmond, EJ PY - 2007/// UR - http://dx.doi.org/10.1109/IEMBS.2007.4352313 ER -