The ascending aorta, or aorta ascendens, along with its constituents, amounts
to about five centimeters in length. It constitutes the initial division of the
aorta, the largest artery in the body. It originates from the upper portion of
the left ventricle of the heart at the aortic valve “on a level with the lower
border of the third costal cartilage behind the left half of the sternum; it
passes obliquely upward, forward, and to the right, in the direction of the
heart’s axis, as high as the upper border of the second right costal cartilage,
describing a slight curve in its course, and being situated, about 6 cm. behind
the posterior surface of the sternum.” (Gray” 1) It then gives rise to the right
and left coronary arteries, which supply the heart muscle. It then curves left
continuing into the arch of the aorta. Originating from the aorta are the right
brachiocephalic trunk, left common carotid, and left subclavian arteries. The
coronary arteries, thus being, the only branches of the ascending aorta.
At the entrance of the ascending aorta are three minute aortic sinuses and the
Aortic Semilunar Valve, a three-cusped valve located at the base of the
ascending aorta behind the sternum at the level of the third intercostal space
(Grine 273). The point at which the ascending aorta converges with the aortic
arch is termed the bulb of the aorta, a swelling due to vessel increasement on
the right wall. Lying superior to the ascending aorta is the trunk of the
pulmonary artery and the auricular appendage of the right atrium. It is
partitioned from the sternum by the serous pericardium, the right pleura, the
anterior margin of the right lung, some loose areolar tissue, and the remains
of the thymus. Posteriorly, it is propped upon the left atrium and right
pulmonary artery. Lying adjacent on the right border is the superior vena cava
and right atrium. Lying opposite on the left border is the pulmonary artery and
pulmonary trunk (Gray” 1). The ascending aorta is, thus, “ a hallowed and
convenient division of the aorta” (“MedicineNet” 1) that supplies blood to most
of the body.
Works Cited
Gray, Henry, http://www.bartleby.com. 21 Apr 2002.
Grine, Fredrick E., Regional Human Anatomy: A Laboratory Workbook for Use with
Models and Prosections. New York, McGraw-Hill Companies, 2002.
http://www.medicinenet.com. 21 Apr 2002.