Effects of autonomic nervous activity and mechanical stress on the arrhythmogenesis in heart failure

本研究采用光学跨膜电位标测技术，研究了机械应激和自主神经刺激对心肌梗死后心力衰竭大鼠心室肌电生理特性的时空效应。1）交感神经刺激缩短心肌梗死后心力衰竭大鼠心室动作电位时程（APD）。非梗死区APD缩短大于梗死区。结果，交感神经刺激增加了APD的不均匀性。刺激迷走神经可降低APD的不均匀性。2）在心电图T波处施加容积脉冲可引起局灶性兴奋。局灶性兴奋起源于梗死周围区域。当在适当的耦合间隔后施加容量脉冲时，诱发的局灶性兴奋发展为心室颤动。3）迷走神经刺激抑制慢性心力衰竭的电重构。

Using optical transmembrane potential mapping, we investigated the spatiotemporal effects of autonomic nerve stimulation and mechanical stress on the electrophysiological characteristics in heart failure rats after myocardial infarction.1) Sympathetic nerve stimulation shortened ventricular action potential duration(APD) in heart failure rats after myocardial infarction. The shortening of APD was larger in the non-infarct area than in the infarct area. As a result, sympathetic nerve stimulation increased inhomogeneity of APD. Vagus nerve stimulation decreased the inhomogeneity of APD.2) The volume pulse applied at the T wave of ECG induced a focal excitation. The focal excitation originated from the surrounding areas of infarction. When the volume pulse was applied after a proper coupling interval, the induced focal excitation developed to ventricular fibrillation.3) Vagus nerve stimulation suppressed electrical remodeling in chronic heart failure.