An otherwise healthy male with a history of systolic arterial hypertension presented to the emergency department (ED) with acute onset of upper back pain, stabbing in nature, with associated shortness of breath. When seen in the ED the patient was noted to be hypotensive and tachycardiac. Physical examination disclosed diminished breath sounds in the left chest, equal pulses in bilateral upper extremities, and diminished bilateral femo-ral pulses. Initial chest x-ray showed a left hemothorax (Figure 10-1). Vascular surgery was consulted and a thin slice computed tomographic (CT) scan with intravenous contrast and three-dimensional reconstruction indicated an acute Stanford B (DeBakey IIIB) aortic dissection with apparent rupture into the left chest (Figure 10-2). A proximal landing zone just distal to the origin of the left subclavian artery was seen. The dissection was seen to extend to the level of the abdominal aortic bifurcation (Figure 10-3). The celiac, superior and inferior mesenteric, and bilateral renal arteries were seen to be patent, and there was no clinical evidence of malperfusion syndrome of the visceral organs. The patient was taken for compassionate off-label use of a thoracic endovascular stent grafting (TEVAR) as his only option for survival. One day later he returned to the operating room for left thoracotomy and evacuation of the hemothorax. Percutaneous tracheostomy was performed several days later at the bedside. Postoperative imaging showed control of the rupture with resolution of the hemothorax and good position of the thoracic endograft (Figures 10-4 and 10-5). The patient was maintained in the intensive care unit (ICU), and after a prolonged hospital course and weaning from the ventilator, he improved and was subsequently discharged home.
Two classification schemes are in common use to define aortic dissections. To define the anatomic landmarks, the takeoff of the left subclavian artery is used as the distal extent of the aortic arch.
The DeBakey classification is as follows:
Type I dissections involve the ascending aorta and the arch and extend beyond the level of the aortic arch.
Type II involves the ascending aorta and the arch only.
Type IIIA involves the descending aorta only, not extending into the abdominal aorta.
Type IIIB involves the abdominal aorta as well as the descending aorta.