International Journal of Bioelectromagnetism Vol. 5, No. 1, p. 380, 2003. |
www.ijbem.org |
Computer Simulation and Cellular Basis
of Takeshi Tsutsumia,
Naoko Zendaa, Hisa Shimojimaa, Masahiko Kondoa,
Youichi Takeyamaa, Daming Weib, Yoshiwo Okamotoc, and Yasuaki
Teramatid aDivision of Cardiology Showa University Fujigaoka
Hospital,227-8501 Yokohama Japan Abstract. The aims of this study
are to investigate the relation of coronary T wave to the distribution of
action potential duration (APD) around MI lesion, and the causes of change
in APD under ischemic-like condition in vitro study. Transmembrane action
potentials were recorded from the endocardial muscle preparations from canine
heart under ischemic-like solution with or without verapamil or lysophosphatidylcholine
(LPC, 0.2mM) or phospholipase C (PLC). The time courses of the APD transitions
were measured. On the above results, computer simulation of antero-septal
MI was reconstructed by Wei-Harumi model. The adequate distributions of APD
around MI lesion by which the coronary T wave can be simulated were searched.
As the results, the transient prolongation of APD compared with that of base
line was noted during the reoxygenation period (rebound phenomenon). The duration
of this phenomenon was lengthened after the LPC, but shortened after PLC,
and no significant changes after verapamil. In conclusions, the appearance
of coronary T wave will be related to the prolonged APD of reperfused myocardial
cell. The long lasting T wave inversion seen in MI might be caused of abnormal
ionic transportation due to fine structural change of lipid cell membrane.
Keywords: Coronary T Wave; Transmembrane Action Potential; Rebound Phenomenon; Computer Simulation
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