The Sympathetic and Parasympathetic Contributions to the Cardiac Plexus: a Fetal Study

Abstract

SUMMARY:The cardiac plexus is formed by sympathetic nerves originating from the superior, middle, inferior cervical or cervicothoracic ganglia as well as from the first to the fifth thoracic ganglia. Furthermore, the vagus nerve and its counterpart, the recurrent laryngeal nerve supply the cardiac plexus with parasympathetic cardiac nerves. This investigation aimed to review and record the medial contributions of the cervical ganglia, first to fifth thoracic ganglia and medial contributions of the vagus and recurrent laryngeal nerves to the cardiac plexus. The study involved bilateral micro-dissection of forty cadaveric fetal specimens (n=80). The origins of sympathetic contributions to the cardiac plexus were described as either ganglionic, inter-ganglionic or from both the ganglion and the inter-ganglionic sympathetic chain. The number of cervical sympathetic ganglia varied from two to five in this study; the superior cervical ganglion was constant while the middle cervical, vertebral, inferior cervical or cervicothoracic ganglia were variable. The prevalence of cardiac nerves were as follows: superior cervical cardiac nerve (95%); middle cervical cardiac nerve (73%); vertebral cardiac nerve (41%); inferior cervical cardiac nerve (21%) and cervicothoracic cardiac nerve (24%). This investigation records the thoracic caudal limit of the thoracic sympathetic contributions to the cardiac plexus as the T5 ganglion. The findings of this study highlight the importance of understanding the medial sympathetic contributions and their variations to the cardiac plexus as this may assist surgeons during minimal access surgical procedures, sympathectomies, pericardiectomies and in the management of diseases like Raynaud's Phenomenon and angina pectoris.

Asymmetry and Heterogeneity: Part and Parcel in Cardiac Autonomic Innervation and Function

“…Human left and right sympathetic and parasympathetic cardiopulmonary nerves connect in the mediastinum, where they form the cardiac plexus. A distinction is made between the superficial (ventral) cardiac plexus, located in between the pulmonary trunk and aortic arch, and the deep (dorsal) cardiac plexus, located between the aorta and trachea ( De Gama et al, 2012 ; Figure 3 ). The superficial and deep cardiac plexuses are not as discrete and confined as for example the cervical and thoracic paravertebral ganglia, but rather describe the locations of interconnecting nerve networks where the number of nerve fibers gradually increases and nerve fibers tend to be more mixed (including sympathetic, parasympathetic and visceral afferent fibers).…”

Antiarrhythmic calcium channel blocker verapamil inhibits trek currents in sympathetic neurons

“…However, we know that the neurons of the parasympathetic intracardiac ganglion (ICG) and sympathetic SCG innervate both muscle fibers and pacemakers. The SCG hosts a critical population of sympathetic neurons projecting to the cardiac tissue (Pather et al, 2003;De Gama et al, 2012), and several studies have suggested that the SCG might be directly implicated in the pathophysiology of different cardiovascular diseases (Hernandez-Ochoa et al, 2009;Kong et al, 2013;Na et al, 2014;Cheng et al, 2018).…”