Limit Cycles in Luo-Rudy I Model

• Main Authors: Kuo-Hsiang Hung, 洪國翔
• Other Authors: Tzyy-Leng Horng
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/86017052576746857615

碩士 === 逢甲大學 === 應用數學所 === 97 === The atria and ventricles consist of myocardial cells which are mainly non-automatic excitable cells, which means these cells can not excite itself without external stimulus. The source of periodic electrical stimulus which causes myocardial cells to excite and contract is form SA node and AV node. SA node and AV node are self-exciting pacemaker in heart, which produce periodic action potentials propagating through the whole heart. If there is something wrong with the conductance of electrical stimulus, for example, failure of SA node and AV node, cardiac arrhythmias even fibrillation can happen in heart, and cause cardiac death. In this research, we conduct the codimension-1 and 2 bifurcation analysis of a popular model for ventricular myocyte, Luo-Rudy I model, to track limit cycle. By adjusting extracellular potassium concentration and maximum conductance of ionic channels, we found non-oscillatory excitable ventricular myocyte can turn into a pacemaker cell which has spontaneous oscillations.