Experimental and Clinical Study on Desynchronization of Biological Rhythms in Heart Failure

目的：为了阐明心力衰竭时体内生物节律的去稳态化，我们预测了1）收缩调节和2）交感神经调节的最佳心脏和呼吸节律，并在3）心力衰竭患者和4）自由活动的清醒心力衰竭大鼠中检测了身体活动、血流动力学和自主神经功能的超昼夜动力学。方法与结果：1）减慢心率似乎有利于心力衰竭心脏节律与缓慢Ca 2+循环的同步。本文应用系统辨识技术建立了心力衰竭患者力-频响应和机械恢复的数学模型，并预测了对Ca ~（2+）循环和心脏泵血能力的最佳心率。2）应用系统辨识技术建立了交感神经活动的呼吸调节模型，并研究了心力衰竭患者有效抑制交感神经活动的最佳呼吸节律。 ...更多信息 re.该模型预测，呼吸节律减少一半，潮气量增加一倍，交感神经活动受到的抑制是对照组的三倍，提示减慢呼吸节律可以有效稳定心力衰竭患者的交感神经张力。3）所有患者的功率谱分析-日心率和体力活动显示，心脏病患者的心率和体力活动均存在明显的超日节律，失败在50%的轻度哈特衰竭受试者中，发现心率和体力活动的昼夜变化具有更显著的超昼夜节律。经总功率标准化的超日功率平均心率为36.3±5.4%，体力活动为38.9±11.5%。然而，体力活动的超日功率的发生率和幅度随着心力衰竭的进展而下降。4）在自由活动的清醒心力衰竭大鼠中检查全天体力活动的超日节律、心率和血压以及自主神经功能的同步性。一个美丽的ultradian节奏的活动被发现在同步与血流动力学和自主神经功能，但显着衰减的幅度在大鼠与heartfail.Conclusions：所有这些研究表明，deserminization的生物节律（活动，血流动力学，和autonimic功能）是心力衰竭的一个特征，减缓的生物节律可能是有效的为他们的deserminization过程。少

Purpose :To elucidate the desynchronization of internal biological rhythms in heart failure, we predicted the optimal cardiac and respiratory rhythms for 1)contractility modulation and 2)sympathetic modulation, and examined ultradian dynamics of physical activity, hemodynamics, and autonomic function in 3)patients with heart failure and 4)free-moving conscious rats with heart failure.Methods & Results :1)Slowing heart rate seems to be beneficial for synchronization of cardiac rhythm with slow Ca2+ cycling in the failing heart. Using system identification technique, we developed a mathematical model of force-frequency response and mechanical restitution in human failing hearts and predicted the optimal heart rate for both Ca2+ cycling and cardiac pumping ability.2)Using system identification technique, we developed a model of respiratory modulation of sympathetic nerve activity and examined the optimal respiratory rhythm for effective sympathetic suppression in patients with heart failu … More re. The model predicted that a reduction of respiratory rhythm by half with doubling tidal volume suppressed sympathetic nerve activity three times greater than control, suggesting that a slowing respiration rhythm could effectively stabilize sympathetic tone in patients with heart failure.3)Power spectral analysis for all-day heart rate and physical activity revealed that a prominent ultradian rhythm existed in both heart rate and physical activity in patients with heart failure. A more prominent ultradian rhythm of circadian changes in heart rate and physical activity was found in 50% of the subjects with mild hart failure. Their ultradian power normalized by the total power averaged 36.3±5.4% in heart rate and 38.9±11.5% in physical activity. However, the incidence and magnitude of the ultradian power of physical activity declined as the heart failure progressed.4)Synchronization of ultradian rhythms of all-day physical activity, heart rate and blood pressure, autonomic function was examined in free-moving conscious rats with heart failure. A beautiful ultradian rhythm of activity was found in synchrony with hemodynamics and autonomic function but markedly attenuated in amplitude in the rat with heart failure.Conclusions :All these studies suggest that desynchronization of biological rhythms(activity, hemodynamics, and autonimic function) is a characteristic feature of heart failure and that slowing the biological rhythms could be effective for their resynchronization processes. Less