Generation and propagation of ectopic beats induced by spatially localized Na-K pump inhibition in atrial network models.
A biophysically detailed two-dimensional network model of the cardiac atrium has been implemented on the Thinking Machines massively parallel CM-5 supercomputer. The model is used to study the effects of spatially localized inhibition of the Na-K pump. Na overloading produced by pump inhibition can induce spontaneous, propagating ectopic beats within the network. At a cell-to-cell coupling value yielding a realistic plane wave conduction velocity of 0.6 m s-1, pump inhibition in roughly 1000 cells can induce propagating ectopic beats in a 512 x 512 lattice of cells.
Winslow
R L
RL
Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Varghese
A
A
Noble
D
D
Adlakha
C
C
Hoythya
A
A
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D016275:Atrial Function; D003198:Computer Simulation; D006321:Heart / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008433:Mathematics; D008564:Membrane Potentials / Q000187:drug effects; D008955:Models, Cardiovascular; D011817:Rabbits; D012964:Sodium / Q000494:pharmacology / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*; D013612:Tachycardia, Ectopic Atrial
D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase