In this section
@article{Ciaccio:2018:10.1016/j.compbiomed.2018.02.018,
author = {Ciaccio, EJ and Peters, NS and Garan, H},
doi = {10.1016/j.compbiomed.2018.02.018},
journal = {COMPUTERS IN BIOLOGY AND MEDICINE},
pages = {175--187},
title = {Effects of refractory gradients and ablation on fibrillatory activity},
url = {http://dx.doi.org/10.1016/j.compbiomed.2018.02.018},
volume = {95},
year = {2018}
}
TY - JOUR
AB - BackgroundThe mechanisms involved in onset, maintenance, and termination of atrial fibrillation are not well understood. A biophysical model could be useful to determine how the events unfold.MethodA two-dimensional cellular automaton consisting of 576×576 grid nodes was implemented to demonstrate the types of electrical activity that may occur in compromised atrial substrate. Electrical activation between nodes was made anisotropic (2:1), and the refractory period (RP) was adjusted from 74 to 192ms in the spatial domain. Presence of collagen fibers were simulated as short lines of conduction block at many random grid sites, while ablation lesions were delineated as longer lines of block. An S1-S2 pulse from one grid corner was utilized to initiate simulated electrical activity. Simulations were done in which 1. no ablation lines, 2. random ablation lines, and 3. parallel ablation lines were added to the grid to determine how this affected the formation and annihilation of rotational activity after S1-S2 stimulation.ResultsAs the premature (S2) wavefront traversed the grid, rotational activity formed near boundaries where wavefronts propagated from shorter to longer refractory regions, causing unidirectional block, and were anchored by fiber clusters. Multiple wavelets appeared when wavefronts originating from different driving rotational features collided, and/or by their encounter with RP discontinuities. With the addition of randomly orientated simulated ablation lesions, followed by reinduction of fibrillatory activity, mean activation interval (AI) prolonged from a baseline level of 144.2ms–160.3ms (p<0.001 in most comparisons). During fibrillatory activity, when parallel ablation lines were added to short RP regions, AI prolonged to 150.4ms (p<0.001), and when added to long RP regions, AI prolonged to 185.3ms (p<0.001). In all cases, AI prolongation after simulated ablation resulted from reduced number and/or from the isolatio
AU - Ciaccio,EJ
AU - Peters,NS
AU - Garan,H
DO - 10.1016/j.compbiomed.2018.02.018
EP - 187
PY - 2018///
SN - 0010-4825
SP - 175
TI - Effects of refractory gradients and ablation on fibrillatory activity
T2 - COMPUTERS IN BIOLOGY AND MEDICINE
UR - http://dx.doi.org/10.1016/j.compbiomed.2018.02.018
UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000430768000017&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR - http://hdl.handle.net/10044/1/60709
VL - 95
ER -