Effective epicardial resistance of rabbit ventricles.
Effective epicardial resistance of rabbit ventricles.
复制标题
兔心室的有效心外膜阻力。
DOI：
10.1114/1.210
复制
发表时间：
1999
影响因子：
3.8
通讯作者：
Knisley,SB
中科院分区：
文献类型：
--
作者：
Baynham,TC;Knisley,SB
本研究评价了动脉灌注兔心脏心室表面的有效阻力。用平行或垂直于心外膜纤维的四电极阵列确定有效电阻。通过用两个平行线电极向心外膜施加电流并测量电极之间区域的电位来确定沿沿着或跨心外膜纤维的电阻。进行计算机模拟以了解心室壁中电流的分布。有效电阻沿沿着纤维与沿纤维没有不同。模拟显示，当电极垂直于心外膜纤维与平行于心外膜纤维定向时，纤维的透壁旋转导致电流分布不同。当阵列定向为使心外膜电流穿过纤维时，跨壁流动并沿着较深纤维流动的电流比例增加，而心外膜流动的电流比例减少。这引入了有效电阻的各向同性。因此，与孤立的心脏纤维相反，由于纤维的透壁旋转，心室心外膜表现出各向同性的有效阻力。旋转和各向同性电阻对于心脏电行为和心室中电流的影响可能是重要的。©1999生物医学工程学会. PAC 99：8719La，8716Uv
This study evaluated effective resistances on the ventricular surfaces of arterially-perfused rabbit hearts. Effective resistances were determined with a four-electrode array that was parallel or perpendicular to epicardial fibers. Resistance along or across epicardial fibers was determined by applying current to the epicardium with two parallel line electrodes and measuring potentials in the region between the electrodes. Computer simulations were performed to gain insight into the distribution of current in the ventricular wall. The effective resistances were not different along versus across fibers. Simulations showed that transmural rotation of fibers causes current to be distributed differently when the electrode is oriented perpendicular versus parallel to epicardial fibers. When the array is oriented so that epicardial current is across fibers, the fraction of current that flows transmurally and along the deeper fibers increases while the fraction of current that flows epicardially decreases. This introduces isotropy of the effective resistance. Thus, in contrast to isolated cardiac fibers, the ventricular epicardium exhibits isotropic effective resistance due to transmural rotation of fibers. The rotation and isotropic resistance may be important for cardiac electrical behavior and effects of electrical current in the ventricles. ©1999 Biomedical Engineering Society.PAC99: 8719La, 8716Uv