Electrical 'hot spot' as a mechanism of defibrillation

Ravi Ranjan, Matthew G. Fishler, Nitish V Thakor

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The excitation threshold of isolated cardiac cells has been shown to be sensitive to the direction of applied electric field. To further explore this relationship, we developed a realistic two-dimensional finite element model of a cardiac cell. The model was used to determine the spatial distributions of transmembrane voltages produced by a uniform electric field applied across the cell. With a 5 V/cm field applied parallel to the cell axis, the maximum absolute transmembrane voltages measured at either end of the cell were 39.1 mV and 46.5 mV (signs depend on polarity of applied field), while 40.5 mV and 44.8 mV with the field perpendicular to the cell axis. More significantly however, we found that these highest potentials were concentrated at distinct sites on the membrane. Thus, we hypothesize that the depolarization of a cell due to the defibrillation shock initiates at one of these 'hot spots' whose exact location depends on the direction and polarity of the field, and shape of the cell. Our computational results are in good agreement with experimental results suggesting that a nonuniform cell shape does have an important bearing on the subsequent excitation thresholds of that cell.

Original languageEnglish (US)
Title of host publicationComputers in Cardiology
PublisherPubl by IEEE
Pages245-246
Number of pages2
ISBN (Print)0818654708
StatePublished - 1993
EventProceedings of the 1993 Conference on Computers in Cardiology - London, UK
Duration: Sep 5 1993Sep 8 1993

Other

OtherProceedings of the 1993 Conference on Computers in Cardiology
CityLondon, UK
Period9/5/939/8/93

Fingerprint

Electric fields
Depolarization
Electric potential
Spatial distribution
Membranes
Cell Shape
Shock

ASJC Scopus subject areas

  • Software
  • Cardiology and Cardiovascular Medicine

Cite this

Ranjan, R., Fishler, M. G., & Thakor, N. V. (1993). Electrical 'hot spot' as a mechanism of defibrillation. In Computers in Cardiology (pp. 245-246). Publ by IEEE.

Electrical 'hot spot' as a mechanism of defibrillation. / Ranjan, Ravi; Fishler, Matthew G.; Thakor, Nitish V.

Computers in Cardiology. Publ by IEEE, 1993. p. 245-246.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ranjan, R, Fishler, MG & Thakor, NV 1993, Electrical 'hot spot' as a mechanism of defibrillation. in Computers in Cardiology. Publ by IEEE, pp. 245-246, Proceedings of the 1993 Conference on Computers in Cardiology, London, UK, 9/5/93.
Ranjan R, Fishler MG, Thakor NV. Electrical 'hot spot' as a mechanism of defibrillation. In Computers in Cardiology. Publ by IEEE. 1993. p. 245-246
Ranjan, Ravi ; Fishler, Matthew G. ; Thakor, Nitish V. / Electrical 'hot spot' as a mechanism of defibrillation. Computers in Cardiology. Publ by IEEE, 1993. pp. 245-246
@inproceedings{5661ddac5faa4dc1ada15425f9767387,
title = "Electrical 'hot spot' as a mechanism of defibrillation",
abstract = "The excitation threshold of isolated cardiac cells has been shown to be sensitive to the direction of applied electric field. To further explore this relationship, we developed a realistic two-dimensional finite element model of a cardiac cell. The model was used to determine the spatial distributions of transmembrane voltages produced by a uniform electric field applied across the cell. With a 5 V/cm field applied parallel to the cell axis, the maximum absolute transmembrane voltages measured at either end of the cell were 39.1 mV and 46.5 mV (signs depend on polarity of applied field), while 40.5 mV and 44.8 mV with the field perpendicular to the cell axis. More significantly however, we found that these highest potentials were concentrated at distinct sites on the membrane. Thus, we hypothesize that the depolarization of a cell due to the defibrillation shock initiates at one of these 'hot spots' whose exact location depends on the direction and polarity of the field, and shape of the cell. Our computational results are in good agreement with experimental results suggesting that a nonuniform cell shape does have an important bearing on the subsequent excitation thresholds of that cell.",
author = "Ravi Ranjan and Fishler, {Matthew G.} and Thakor, {Nitish V}",
year = "1993",
language = "English (US)",
isbn = "0818654708",
pages = "245--246",
booktitle = "Computers in Cardiology",
publisher = "Publ by IEEE",

}

TY - GEN

T1 - Electrical 'hot spot' as a mechanism of defibrillation

AU - Ranjan, Ravi

AU - Fishler, Matthew G.

AU - Thakor, Nitish V

PY - 1993

Y1 - 1993

N2 - The excitation threshold of isolated cardiac cells has been shown to be sensitive to the direction of applied electric field. To further explore this relationship, we developed a realistic two-dimensional finite element model of a cardiac cell. The model was used to determine the spatial distributions of transmembrane voltages produced by a uniform electric field applied across the cell. With a 5 V/cm field applied parallel to the cell axis, the maximum absolute transmembrane voltages measured at either end of the cell were 39.1 mV and 46.5 mV (signs depend on polarity of applied field), while 40.5 mV and 44.8 mV with the field perpendicular to the cell axis. More significantly however, we found that these highest potentials were concentrated at distinct sites on the membrane. Thus, we hypothesize that the depolarization of a cell due to the defibrillation shock initiates at one of these 'hot spots' whose exact location depends on the direction and polarity of the field, and shape of the cell. Our computational results are in good agreement with experimental results suggesting that a nonuniform cell shape does have an important bearing on the subsequent excitation thresholds of that cell.

AB - The excitation threshold of isolated cardiac cells has been shown to be sensitive to the direction of applied electric field. To further explore this relationship, we developed a realistic two-dimensional finite element model of a cardiac cell. The model was used to determine the spatial distributions of transmembrane voltages produced by a uniform electric field applied across the cell. With a 5 V/cm field applied parallel to the cell axis, the maximum absolute transmembrane voltages measured at either end of the cell were 39.1 mV and 46.5 mV (signs depend on polarity of applied field), while 40.5 mV and 44.8 mV with the field perpendicular to the cell axis. More significantly however, we found that these highest potentials were concentrated at distinct sites on the membrane. Thus, we hypothesize that the depolarization of a cell due to the defibrillation shock initiates at one of these 'hot spots' whose exact location depends on the direction and polarity of the field, and shape of the cell. Our computational results are in good agreement with experimental results suggesting that a nonuniform cell shape does have an important bearing on the subsequent excitation thresholds of that cell.

UR - http://www.scopus.com/inward/record.url?scp=0027808669&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027808669&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:0027808669

SN - 0818654708

SP - 245

EP - 246

BT - Computers in Cardiology

PB - Publ by IEEE

ER -