Traumatic Thoracic Aortic Pseudoaneurysm (TAPA) is an uncommon condition, and is extremely rare to have an undiagnosed post-traumatic thoracic aortic aneurysm (TTAA) and/or aortic rupture for this incredible length of time due to the advances and availability of imaging studies. Furthermore, this injury is most often lethal and very few patients survive the initial insult. However, those that survive the acute phase may have aortic rupture that goes undiagnosed, occasionally leading to the formation of a chronic TTAA. The recommendation is to treat these aneurysms electively due to the most common complication being rupture, which is another lethal complication.

Figure 3: CT scan of chest showing a 4.3 cm × 4.5 cm aneurysm of the ascending aorta.

A 75 year-old female presented to our department for evaluation of a TAPA found incidentally on Computed Tomography (CT) 3 months prior. The pseudoaneurysm was found during a routine cardiac evaluation prior to an elective left total knee replacement. The CT scan indicated a pseudoaneurysm of 4.3×4.5 cm in diameter (Figure 1). The patient was involved in a motor vehicle accident (MVA) and subsequent deceleration injury in 1974, at which time she suffered a lung contusion, ruptured bladder, liver laceration, and laceration of the thoracic aorta that went undetected. The patient underwent elective aneurysmal repair by first creating a Carotid-Subclavian bypass followed by thoracic endovascular vascular aortic repair (TEVAR) on post-op day 2 (Figure 2). She tolerated both procedures well and was discharged on post-op day 3.

Figure 4: Angiogram showing pseudoaneurysm of the ascending aorta (left) and repair of pseudosneurysm via TEVAR on post-op day 2 (right).

TEVAR is becoming an increasingly popular treatment option for the management of TTAA, due to decreased length of stay, fewer complications and rapid recovery, as well as an increased quality of life compared to open aortic repair 1. One potential disadvantage is the covering up of the Left Subclavian Artery (LSA) to ensure an adequate landing zone. It has been reported that the incidence of intentional occlusion of the LSA in order to ensure an adequate seal is necessary in 10-50% of patients undergoing TEVAR 2. Consequences have been described as upper extremity ischemia, stroke, spinal cord ischemia, and in patients with left mammary-LAD bypass, MI 3, 4. Currently, the Society of Vascular Surgery recommends preoperative revascularization in all elective cases requiring LSA coverage to prevent the uncommon but potential devastating effects of this elective 3 surgery . LSA revascularization is not without consequences itself. Rare complications reported in the literature have included asymptomatic phrenic nerve palsy, ipsilateral vocal cord paralysis due to recurrent laryngeal nerve damage, vagus 1 nerve injury, thoracic duct injury, lymphocele and Horner’s syndrome 5, 6, 7. Methods include carotid-subclavian bypass and carotid-subclavian transposition. Bypass is many times preferred due to better exposure of the subclavian artery.

We describe a rare case of a MVA victim who suffered aortic laceration that went undiagnosed and developed into a chronic TAPA. The patient presented 38 years later with an asymptomatic TAPA treated successfully with cerebrovascular 5 revascularization followed by TEVAR. Treatment guidelines for chronic TTAA are lacking and further studies are necessary to develop a standardized approach for this lethal condition.

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2. Feezor, RJ.; Lee, WA. “Management of the left subclavian artery during TEVAR.” Seminars in Vascular Surgery, v. 22 issue 3, 2009, p. 159-64.
3. Matsumura, JS., et al. “The Society for Vascular Surgery Practice Guidelines: management of the left subclavian artery with thoracic endovascular aortic repair.”Journal of Vascular Surgery, v. 50 issue 5, 2009, p. 1155-8.
4. Chung, J., et al. “Left subclavian artery coverage during thoracic endovascular aortic repair and risk of perioperative stroke or death.” Journal of Vascular Surgery, v. 54 issue 4, 2011, p. 979-84.
5. Woo, EY., et al. “Left subclavian artery coverage during thoracic endovascular aortic repair: a single-center experience.” Journal of Vascular Surgery, v. 48 issue 3, 2008, p. 555-60.
6. Peterson, BG.; Eskandari, MK.; Gleason, TG.;
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