Title :
Graded effects of pulsed electric fields on contractility of single heart cells
Author :
Mulligan, M.R. ; O´Neill, Rory J. ; Zei, Paul C. ; Tung, Leslie
Author_Institution :
Dept. of Biomed. Eng., Johns Hopkins Univ., Baltimore, MD, USA
Abstract :
The effects of high-intensity electric fields on excitability and contractility of the heart at the cellular level are pertinent to defibrillation and electrical ablation. Stimulation of single cardiac cells with a rectangular pulsed electric field elicits twitch contraction. Variation of the stimulus intensity and duration shows a distinct strength-duration curve for the threshold of excitation, T1. T1 is mediated by the cell orientation with respect to the electric field (parallel or perpendicular). Above the threshold level is a second threshold level, T2, for cellular contracture. T2 has a shape similar to that of T1, and may be a consequence of formation of pores in the cell membrane (electroporation).<>
Keywords :
bioelectric phenomena; biological effects of fields; cardiology; cellular biophysics; cell membrane pore formation; cell orientation; contractility; defibrillation; electrical ablation; electroporation; excitability; excitation threshold; graded effects; high-intensity electric fields; pulsed electric fields; rectangular pulsed electric field; single heart cells; stimulus duration; stimulus intensity; strength-duration curve; threshold level; twitch contraction;
Conference_Titel :
Engineering in Medicine and Biology Society, 1988. Proceedings of the Annual International Conference of the IEEE
Conference_Location :
New Orleans, LA, USA
Print_ISBN :
0-7803-0785-2
DOI :
10.1109/IEMBS.1988.95240
