Roles of line stimulation-induced virtual electrodes and action potential prolongation in arrhythmic propagation

dc.contributor.author	Baynham, TC	en
dc.contributor.author	Knisley, SB	en
dc.date.accessioned	2014-06-06T06:44:27Z
dc.date.available	2014-06-06T06:44:27Z
dc.date.issued	2001	en
dc.identifier.issn	10453873	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/1883
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0034745611&partnerID=40&md5=038050120592e5eea7b5b0671da33750	en
dc.subject	Arrhythmias	en
dc.subject	Line stimulation	en
dc.subject	Transmembrane voltage	en
dc.subject	Virtual electrodes	en
dc.subject.other	action potential	en
dc.subject.other	animal experiment	en
dc.subject.other	animal tissue	en
dc.subject.other	article	en
dc.subject.other	electrostimulation	en
dc.subject.other	fluorescence	en
dc.subject.other	heart arrhythmia	en
dc.subject.other	nonhuman	en
dc.subject.other	polarization	en
dc.subject.other	priority journal	en
dc.subject.other	rabbit	en
dc.subject.other	statistical analysis	en
dc.subject.other	stimulus response	en
dc.subject.other	animal	en
dc.subject.other	computer simulation	en
dc.subject.other	electrode	en
dc.subject.other	heart	en
dc.subject.other	pathophysiology	en
dc.subject.other	physiology	en
dc.subject.other	spectrofluorometry	en
dc.subject.other	heart pacing	en
dc.subject.other	methodology	en
dc.subject.other	pericardium	en
dc.subject.other	time	en
dc.subject.other	Action Potentials	en
dc.subject.other	Animals	en
dc.subject.other	Arrhythmia	en
dc.subject.other	Computer Simulation	en
dc.subject.other	Data Interpretation, Statistical	en
dc.subject.other	Electrodes	en
dc.subject.other	Heart	en
dc.subject.other	Rabbits	en
dc.subject.other	Spectrometry, Fluorescence	en
dc.subject.other	Cardiac Pacing, Artificial	en
dc.subject.other	Electric Stimulation	en
dc.subject.other	Electrodes, Implanted	en
dc.subject.other	Pericardium	en
dc.subject.other	Time Factors	en
dc.title	Roles of line stimulation-induced virtual electrodes and action potential prolongation in arrhythmic propagation	en
heal.type	journalArticle	en
heal.publicationDate	2001	en
heal.abstract	Arrhythmias During Line Stimulation. Introduction: Line stimulation across fibers generates a virtual electrode (VE) pattern that consists of adjacent +Vm and -Vm regions. In this study, we evaluated Vm at the break of line stimulation pulses to determine where arrhythmias arise and their propagation direction relative to +Vm and -Vm regions. Methods and Results: We optically mapped the anterior left ventricular epicardium of isolated rabbit hearts (n = 9). Monophasic line stimuli were applied across fibers at various coupling intervals. In 18 of 24 break arrhythmias, i.e., arrhythmias in which propagation occurred after the break but ≤30 msec postshock, excitation propagated from the border between +Vm and -Vm regions toward the -Vm region (P < 0.05) for either shock polarity, even though locations of positive and negative Vm changed with shock polarity. In 13 of 18 make arrhythmias, i.e., arrhythmias in which propagation occurred before the break, the excitation propagated from the center of the +Vm region toward the -Vm regions (P < 0.05). For late arrhythmias, i.e., arrhythmias in which propagation was found >30 msec postshock, propagation was reversed, i.e., toward the +Vm region (P < 0.01), which was where the positive VE produced action potential prolongation. Conclusion: The propagation of break, make, and late arrhythmias is spatially related to VEs. The different direction of propagation of late arrhythmias relative to the VEs is explained by the delayed recovery of Vm due to VE-induced action potential prolongation.	en
heal.journalName	Journal of Cardiovascular Electrophysiology	en
dc.identifier.issue	2	en
dc.identifier.volume	12	en
dc.identifier.spage	256	en
dc.identifier.epage	263	en