학술논문

Defibrillation-shock excitation in a single cardiac fiber
Document Type
Conference
Source
Proceedings of the 19th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 'Magnificent Milestones and Emerging Opportunities in Medical Engineering' (Cat. No.97CH36136) Engineering in medicine and biology Engineering in Medicine and Biology Society, 1997. Proceedings of the 19th Annual International Conference of the IEEE. 1:407-409 vol.1 1997
Subject
Bioengineering
Electric shock
Extracellular
Defibrillation
Biomembranes
Myocardium
Kinetic theory
Protocols
Biomedical engineering
Monitoring
Cathodes
Language
ISSN
1094-687X
Abstract
This modeling study examines the morphology of the action potentials generated in diastole by defibrillation-strength extracellular stimulation. A single cardiac strand of length 4 mm is considered. The membrane kinetics is represented by the Luo-Rudy II model. Stimulation is performed with a S1-S2 protocol of 300 ms coupling interval. Shocks of various strengths are delivered, and action potential magnitudes and upstroke velocities are monitored along the fiber. Under the cathode, the calculated S2 action potentials have larger magnitudes and upstroke velocities than paced activation. Under the anode, a multiphasic transmembrane potential change was observed that resembled a puzzling experimental recording by Zhou et al. (1996). A possible explanation of the observed behavior is provided.