Nakagawa M, Iwao T, Abe H, Ishida S, Takahashi N, Fujino T, Yonemochi H, Saikawa T, Ito M
Department of Laboratory Medicine, Oita Medical University, Japan.
J Electrocardiol. 2000 Jan;33(1):17-22. doi: 10.1016/s0022-0736(00)80096-5.
We recently reported that signal averaged electrocardiograms (SAECG) measurements possess a circadian rhythm and are closely related to heart rate or heart rate variability in healthy volunteers. This study determines the influence of autonomic tone on the filtered QRS (f-QRS) duration from SAECG by using pharmacologic autonomic blockade and exercise in healthy volunteers. Eleven healthy male volunteers were studied. Three protocols were designed to study the effects of exercise (Ex) under control conditions, beta adrenergic blockade or double blockade. SAECGs and heart rate variability (LF and HF: low and high frequency power, LF/HF ratio) were determined from Holter recordings. Ex significantly decreased the f-QRS duration and HF and significantly increased heart rate and LF/HF. Ex during beta adrenergic blockade significantly increased heart rate and decreased f-QRS duration and HF, but did not change LF/HF. Ex during double blockade did not affect the f-QRS duration, HF, or LF/HF. The changes in f-QRS duration induced during Ex, autonomic blockade, or both were inversely correlated with changes in heart rate and LF/HF and positively correlated with changes in HF. These data suggest that f-QRS duration in healthy subjects is shortened by Ex with increased sympathetic tone or decreased parasympathetic tone or the combination.
我们最近报道，在健康志愿者中，信号平均心电图（SAECG）测量具有昼夜节律，且与心率或心率变异性密切相关。本研究通过对健康志愿者进行药物自主神经阻滞和运动，来确定自主神经张力对SAECG中滤波后的QRS（f-QRS）时限的影响。对11名健康男性志愿者进行了研究。设计了三个方案来研究在对照条件下、β肾上腺素能阻滞或双重阻滞时运动（Ex）的影响。从动态心电图记录中测定SAECG和心率变异性（LF和HF：低频和高频功率，LF/HF比值）。运动显著缩短了f-QRS时限和HF，并显著增加了心率和LF/HF。β肾上腺素能阻滞期间运动显著增加了心率，缩短了f-QRS时限和HF，但未改变LF/HF。双重阻滞期间运动未影响f-QRS时限、HF或LF/HF。运动、自主神经阻滞或两者同时引起的f-QRS时限变化与心率和LF/HF变化呈负相关，与HF变化呈正相关。这些数据表明，健康受试者中，运动通过增加交感神经张力或降低副交感神经张力或两者结合，使f-QRS时限缩短。
