Non-traumatic aortic dissection

Patients with acute aortic syndromes (AAS) are often presenting with abrupt chest pain. The presence of blood between intima and media of the aortic wall is the pathologic hallmark of all AAS. The peak of frequency for AAS is around 60 years of age in hypertensive patients. However, younger patients with congenital defects of the collagen can also be affected. Three main processes are recognised: 1) Acute aortic dissection (AD: 60 - 88%), 2) parietal aortic haematoma (PHA: 10 - 30%), and 3) penetrating aortic ulcer (< 10%). When involving the ascending aorta, these three entities are considered surgical emergencies since they can result unexpectedly in pericardial tamponade, or acute aortic regurgitation responsible for pulmonary oedema. Obstruction of aortic branches by the intimal flap or dynamic compression may result in end-organ malperfusion, and a variety of clinical presentations depending on the organs affected. The mortality is very high during the first 48 hours (close to 50%) and justifies emergent open surgery to close the intimal tear in order to depressurise the false lumen and reduce potential malperfusions. If the repair involves the aortic arch, a circulatory arrest under hypothermia will be mandatory. It is now increasingly frequent to perform hybrid surgeries associating placement of endovascular prosthesis in addition to open repairs in order to reduce the occurrence of secondary complications.