Amar Ani, Zlochiver Sharon, Barnea Ofer
Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel.
PLoS One. 2018 Jan 17;13(1):e0191238. doi: 10.1371/journal.pone.0191238. eCollection 2018.
Mechano-electric feedback affects the electrophysiological and mechanical function of the heart and the cellular, tissue, and organ properties. To determine the main factors that contribute to this effect, this study investigated the changes in the action potential characteristics of the ventricle during contraction. A model of stretch-activated channels was incorporated into a three-dimensional multiscale model of the contracting ventricle to assess the effect of different preload lengths on the electrophysiological behavior. The model describes the initiation and propagation of the electrical impulse, as well as the passive (stretch) and active (contraction) changes in the cardiac mechanics. Simulations were performed to quantify the relationship between the cellular activation and recovery patterns as well as the action potential durations at different preload lengths in normal and heart failure pathological conditions. The simulation results showed that heart failure significantly affected the excitation propagation parameters compared to normal condition. The results showed that the mechano-electrical feedback effects appear to be most important in failing hearts with low ejection fraction.
机械电反馈影响心脏的电生理和机械功能以及细胞、组织和器官特性。为了确定导致这种效应的主要因素，本研究调查了收缩期心室动作电位特征的变化。将牵张激活通道模型纳入收缩期心室的三维多尺度模型，以评估不同预负荷长度对电生理行为的影响。该模型描述了电冲动的起始和传播，以及心脏力学中的被动（拉伸）和主动（收缩）变化。进行模拟以量化正常和心力衰竭病理状态下不同预负荷长度时细胞激活和恢复模式以及动作电位持续时间之间的关系。模拟结果表明，与正常情况相比，心力衰竭显著影响兴奋传播参数。结果表明，机械电反馈效应在射血分数低的衰竭心脏中似乎最为重要。
