What is the great plexuses of the sympathetic system?

What it is

• The great plexuses of the sympathetic are aggregations of nerves and ganglia, situated in the thoracic, abdominal, and pelvic cavities, and named the cardiac, celiac, and hypogastric plexuses. They consist not only of sympathetic fibers derived from the ganglia, but of fibers from the medulla spinalis, which are conveyed through the white rami communicantes. From the plexuses branches are given to the thoracic, abdominal, and pelvic viscera. The Cardiac Plexus (Plexus Cardiacus) .
• —The cardiac plexus is situated at the base of the heart, and is divided into a superficial part, which lies in the concavity of the aortic arch, and a deep part, between the aortic arch and the trachea. The two parts are, however, closely connected. The superficial part of the cardiac plexus lies beneath the arch of the aorta, in front of the right pulmonary artery.
• It is formed by the superior cardiac branch of the left sympathetic and the lower superior cervical cardiac branch of the left vagus. A small ganglion, the cardiac ganglion of Wrisberg, is occasionally found connected with these nerves at their point of junction. This ganglion, when present, is situated immediately beneath the arch of the aorta, on the right side of the ligamentum arteriosum.
• The superficial part of the cardiac plexus gives branches ( a ) to the deep part of the plexus; ( b ) to the anterior coronary plexus; and ( c ) to the left anterior pulmonary plexus.