The aortic isthmus is the most common site of occurrence of a traumatic aortic rupture.
The aortic isthmus is the connection between the ascending and descending aorta. It is the site just distal to where the left subclavian artery branches off the aorta. Traumatic aortic ruptures are commonly caused by decelerating motor vehicle accidents. Other areas of aortic disruption can occur at the cardiac root, the attachment of the ligamentum arteriosum, and the passage through the diaphragm.
Butler et al. discuss post-traumatic stress reactions after motor vehicle accidents (MVAs). Over 3 million people are injured in MVAs each year, and many of these individuals will undergo post-traumatic stress and anxiety regarding the incident. Physicians are in a unique position within society to encourage safe driving habits and seat-belt use in an attempt to reduce vehicle accident trauma.
Mirhosseini et al. report on the surgical management of traumatic rupture of the aortic isthmus. This condition is a surgical emergency with a high mortality rate. Open surgical repair is the standard treatment for the majority of patients. One of the major risks of surgical repair is a postoperative paraplegia secondary to spinal cord ischemia.
Illustration A depicts the anatomic site of the aortic isthmus. Illustration B is a CT scan showing a sagittal oblique view of an aortic transection distal to the left subclavian artery.
Answers 1,2,4,5: None of these anatomic sites are the most common site for aortic injury after a traumatic event.
Butler DJ, Moffic HS, Turkal NW. Post-traumatic stress reactions following motor vehicle accidents. Am Fam Physician. 1999 Aug;60(2):524-31. Review.
PMID:10465227 (Link to Abstract)
Mirhosseini SM, Asadollahi S, Fakhri M. Surgical management of traumatic rupture of aortic isthmus: a 25-year experience. Gen Thorac Cardiovasc Surg. 2013 Apr;61(4):212-7. doi: 10.1007/s11748-012-0197-x.
PMID:23266904 (Link to Abstract)
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