Medium cardiac nerve - (n. cardiacis medius bna, jna) - a paired fan-shaped diverging nerve of the second order, extending from the right cervical sympathetic trunk and heading to the atria, aorta and its branches to the left ventricle.
The nerve is cone-shaped and resembles a “herringbone” in cross-section. It has 3-4 posterior and two anterior branches. The posterior branches are directed to the walls of the left atrium and flow into the walls of the vagus nerve, which is separated from the wall of the atrium by connective tissue. The anterior branches are directed to the mouths of the veins of the heart, as well as to the anterior surface of the pulmonary trunk. The posterior and anterior trunks connect to form a canal,