Aortic dissection is a rare, potentially fatal complication generally afflicting the elderly, hypertensive population. In rare cases, aortic dissection has been reported following chest trauma. The following details such a case with a traumatically-induced aortic dissection resulting from blunt trauma received during a motor vehicle accident. While transmural aortic transections frequently coincide with rapid deceleration injuries, aortic dissection remains an uncommon occurrence. In review of the available literature, only twenty-five such cases of traumatic aortic dissection have been reported. This case illustrates the importance of initial clinical examinations and diagnostic imaging in the successful identification of this rare complication.

An 86-year-old, morbidly obese female presented to the emergency department (ED) following a motor vehicle collision in which she was the restrained front seat passenger. According to emergency medical services, the woman was involved in a car collision in which airbag deployment resulted in blunt trauma to the chest and abdomen. At the scene, the patient was alert and able to recall the accident, suggesting no loss of consciousness occurred. The patient had an extensive past medical history, which included the use of warfarin for treatment of lower extremity deep venous thrombosis (DVT) and uncontrolled hypertension.

Figure 1. DeBakey type IIIb refers to dissections that originate distal to the left subclavian artery, extend only distally and may extend below the diaphragm [2].

Upon ED arrival, the patient complained of severe chest pain. Clinical examination revealed an area of ecchymosis involving her anterior chest wall and a softly distended abdomen, consistent with the safety restraint of the vehicle. Initial chest x-ray (CXR) revealed a left pneumothorax and a widened mediastinum, prompting suspicion for aortic injury. The patient was hemodynamically stable in the ED and subsequently underwent computed tomography (CT) scanning of her chest and abdomen with IV contrast. Chest and abdomen CT scans revealed an aortic dissection which began just distal to the left subclavian artery and extended into the abdominal aorta (Figure 1). The patient’s daughter reported that her mother had recent CT chest imaging with no history of an aortic dissection, leading the medical staff to conclude the complication resulted from the blunt trauma received during the vehicle collision. Due to the extensive nature of the patient’s aortic dissection, she was not a surgical candidate. Treatment was limited to strict blood pressure and heart rate control. Three hours after instatement of the treatment protocol, the patient went into cardiac arrest where she was revived using cardiopulmonary resuscitation. Following the progression of her mother’s condition, the patient’s daughter opted to refuse future resuscitation. The patient died shortly thereafter.

Traumatic aortic dissection following blunt trauma is an extremely uncommon, potentially fatal complication. The mechanism of injury, clinical findings, and initial CXR in this case should prompt a high level of suspicion for an aortic injury. This report exemplifies the need for expeditious diagnostic imaging for successfully identifying aortic dissection. If clinicians are not scrupulous in the initial clinical examination, aortic dissection may be overlooked in up to 39% of cases due to the variability of presenting symptoms [1].

In non-trauma patients, aortic dissection typically results from cystic medial necrosis, a degenerative disease characterized by the loss of muscle and elastic fibers of the aortic media frequently afflicting the elderly, hypertensive population. Aortic dissection occurs when degeneration of the aortic media prompts a lesion of the intima, causing blood flow between layers of the aortic wall. As blood flows out of the true aortic lumen into the false lumen created by this lesion, it can dissect for varying distances before either reentering the true lumen, or bursting through the outer layer of the aortic wall, causing a traumatic aortic rupture.

While most aortic dissections are transmural, resulting in a localized transection just distal to the ligamentum arteriosum [3], this case illustrates a ‘dissection’ of the aorta, similar to the dissections seen in the elderly from cystic medial necrosis, secondary to poorly controlled hypertension. In review of the available literature, only twenty-five cases of traumatic aortic ‘dissection’ have been reported [4-28], of which the majority occurred in the descending aorta (thoracic or abdominal). Desai et al. reported the case of an abdominal aortic dissection following administration of the Heimlich maneuver to a 78-year-old woman [4]. Similarly, Oliva et al. discovered a dissection of the thoracic aorta of a 74-year-old man who received blunt trauma in the form of a kick to his abdomen [5]. Although unusual traumatically-induced aortic dissections such as those outlined previously were found, the majority of the cases resulted from motor vehicle accidents. Specifically, 12 of the 25 aortic dissection case reports examined were motor vehicle accident induced [6-8, 16-19, 24-27]. Zisis et al. reported the case of a 45-year-old male who suffered severe thoracic injury during a vehicle collision which resulted in a type B aortic dissection [7]. Additionally, Maleux et al. detailed the case of a 57-year-old woman who suffered a distal abdominal aortic dissection following a frontal car crash [19]. Interestingly, the majority of the traumatically-induced aortic dissection cases present in the available literature occurred in the older adult population (≥ 55).

In summary, we report the rare case of a Debakey type IIIb aortic dissection following blunt trauma. To our knowledge, this is the 26th reported traumatically-induced aortic dissection and only the 13th case resulting from a motor vehicle accident. In review of available literature, the majority of traumatically-induced aortic dissections originate in the descending aorta. As was administered to this patient, the mainstay of treatment for this type of dissection is medical with strict blood pressure control with beta blockage.