生理状态下心脏节律活动受窦房结的自律性控制，而窦房结自律性细胞的活动受交感神经及迷走神经的双重支配。窦房结自律细胞对迷走神经兴奋作用的反应要明显快于对交感神经的反应。这就使得迷走神经能够基本控制心搏节律，交感神经起辅助作用［１］。心率变异（ＨＲＶ）是反映 Cardiac rhythmic activity under physiological conditions is controlled by the sinoatrial node autonomic, while the activity of the self-regulating cells in the sinus node is dominated by the sympathetic and vagal nerves. The reaction of the sinus node autonomic cells to the vagus nerve excitement was significantly faster than that of the sympathetic nerve. This makes the vagus nerve can basically control the heart rhythm, sympathetic nerves play a supporting role [1]. Heart rate variability (HRV) is reflected