Excerpt

Acute aortic syndrome (AAS) groups are life-threatening conditions affecting the aortic wall. AAS are characterized by a disruption of the medial layer of the aorta and consist of acute aortic dissection (AD), intramural hematoma (IMH), and penetrating aortic ulcer (PAU).1 Aortic dissection is the most common form of AAS, IMH, and PAU representing only 10% of AAS. Acute aortic dissection and intramural hematoma share similar clinical features and complications, but have different pathophysiological mechanisms.2 Acute aortic dissection is characterized by the presence of an entry tear that typically occurs spontaneously, whereas intramural hematoma is caused by the rupture of vasa vasorum in the media. IMH can, however, progress to dissection if the intimal layer ruptures. PAU are mostly caused by the ulceration of complex atherosclerotic plaques. Patients with AD of the ascending thoracic aorta and with PAU3 have poor spontaneous prognosis and require urgent open surgery. In patients with IMH, about one third of the patients evolve towards complete aortic dissection. In patients with AAS involving the aortic arch and the descending thoracic aorta, a multidisciplinary approach is required to select the optimal treatment for each patient among open surgery, endovascular intervention, or medical management. Open surgery involving the descending thoracic aorta is complex and can be complicated by paraplegia or paraparesis in case of occlusion of the Adamkiewicz artery perfusing the spinal cord that can occur in around 5% of patients.4 In the past 10 years, significant progresses have been made in endovascular approaches of AAS. Dedicated vascular prosthesis has been developed for thoracic endovascular aortic repair (TEVAR) and are associated with less complication than open surgery. TEVAR has become the treatment of choice in AD of the descending aorta with malperfusion syndrome with a technical success rate of 90%.5 However, complications such as endoleak, aneurysms of the distal aorta, or continued false lumen perfusion, have been described in 5–10% of patients.5 TEVAR appears also as a safe technique for complicated type B IMH, providing very good long-term results.6 However, TEVAR can be complicated by retrograde AD or pseudoaneurysm in patients with IMH.7 The search for factors predictive of poor outcome is thus important to select the patients with AAS that will benefit the most from interventional endovascular treatments at the expense of complications of prosthesis in a minority of them. …