Ang Richard, Marina Nephtali
Centre for Cardiovascular and Metabolic Neuroscience, Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom.
Division of Medicine, University College London, London, United Kingdom.
Front Physiol. 2020 Mar 18;11:236. doi: 10.3389/fphys.2020.00236. eCollection 2020.
Sudden cardiac death caused by ventricular arrhythmias is among the leading causes of mortality, with approximately half of all deaths attributed to heart disease worldwide. Periodic repolarization dynamics (PRD) is a novel marker of repolarization instability and strong predictor of death in patients post-myocardial infarction that is believed to occur in association with low-frequency oscillations in sympathetic nerve activity. However, this hypothesis is based on associations of PRD with indices of sympathetic activity that are not directly linked to cardiac function, such as muscle vasoconstrictor activity and the variability of cardiovascular autospectra. In this review article, we critically evaluate existing scientific evidence obtained primarily in experimental animal models, with the aim of identifying the neuronal networks responsible for the generation of low-frequency sympathetic rhythms along the neurocardiac axis. We discuss the functional significance of rhythmic sympathetic activity on neurotransmission efficacy and explore its role in the pathogenesis of ventricular repolarization instability. Most importantly, we discuss important gaps in our knowledge that require further investigation in order to confirm the hypothesis that low frequency cardiac sympathetic oscillations play a causative role in the generation of PRD.
室性心律失常导致的心脏性猝死是主要的死亡原因之一，全球约有一半的死亡归因于心脏病。周期性复极动力学（PRD）是复极不稳定的一种新标志物，也是心肌梗死后患者死亡的有力预测指标，据信它与交感神经活动的低频振荡有关。然而，这一假设是基于PRD与交感神经活动指标之间的关联，而这些指标与心脏功能并无直接联系，如肌肉血管收缩活动和心血管自谱的变异性。在这篇综述文章中，我们批判性地评估了主要在实验动物模型中获得的现有科学证据，目的是确定负责沿神经心脏轴产生低频交感神经节律的神经网络。我们讨论了节律性交感神经活动对神经传递效率的功能意义，并探讨了其在心室复极不稳定发病机制中的作用。最重要的是，我们讨论了我们知识中的重要空白，这些空白需要进一步研究以证实低频心脏交感神经振荡在PRD产生中起因果作用的假设。
