Aortic dissection

Aortic dissection typically presents with abrupt onset chest, back, or abdominal pain that is severe in intensity or is described as 'sharp' or 'stabbing', particularly in the patient with a high risk condition (such as Marfan syndrome) or a family history of aortic disease. Although a typical patient with aortic dissection is a male in his 50s, always consider the diagnosis in younger patients even if they have no risk factors.

Other features include syncope, heart/renal failure, and mesenteric or limb ischaemia; institute oxygen/advanced life support protocol and haemodynamic support without delay if you suspect dissection.

ECG, chest x-ray, transthoracic echocardiography (depending on local availability), and blood tests (to detect complications of aortic dissection or other differentials) are required for initial diagnostic work-up for all patients. Computed tomography scan is first-line for definitive diagnosis. Further investigations may include trans-oesophageal echocardiography, magnetic resonance imaging, and D-dimer.

Involvement of the ascending aorta and/or arch (Stanford type A) warrants urgent surgical repair. Dissections of the descending aorta (Stanford type B) are managed medically to control the patient’s heart rate and blood pressure; surgery in this group is reserved for those with complications such as rupture, visceral or extremity ischaemia, or persistent or recurrent pain.

Lifelong surveillance is needed with regular imaging to detect complications which may later require surgery.

Aortic dissection describes the condition when a separation has occurred in aortic wall intima, causing blood flow into a new false channel composed of the inner and outer layers of the media. Dissection most commonly occurs with a discrete intimal tear, but can occur without one. Type A dissection involves the ascending aorta with or without involvement of the arch and descending aorta.[1]Crawford ES, Svensson LG, Coselli JS, et al. Surgical treatment of aneurysm and/or dissection of the ascending aorta, transverse aortic arch, and ascending aorta and transverse aortic arch. Factors influencing survival in 717 patients. J Thorac Cardiovasc Surg. 1989 Nov;98(5 Pt 1):659-73. http://www.ncbi.nlm.nih.gov/pubmed/2811404?tool=bestpractice.com ​ Type B does not involve the ascending aorta, and predominantly involves only the descending thoracic (distal to the left subclavian artery) and/or abdominal aorta.​[1]Crawford ES, Svensson LG, Coselli JS, et al. Surgical treatment of aneurysm and/or dissection of the ascending aorta, transverse aortic arch, and ascending aorta and transverse aortic arch. Factors influencing survival in 717 patients. J Thorac Cardiovasc Surg. 1989 Nov;98(5 Pt 1):659-73. http://www.ncbi.nlm.nih.gov/pubmed/2811404?tool=bestpractice.com The European Society of Cardiology defines timeframes for aortic dissection as acute (1-14 days), subacute (15-90 days), and chronic (>90 days).[2]Erbel R, Aboyans V, Boileau C, et al; ESC Committee for Practice Guidelines. 2014 ESC guidelines on the diagnosis and treatment of aortic diseases: document covering acute and chronic aortic diseases of the thoracic and abdominal aorta of the adult. Eur Heart J. 2014 Nov 1;35(41):2873-926. https://academic.oup.com/eurheartj/article/35/41/2873/407693/2014-ESC-Guidelines-on-the-diagnosis-and-treatment http://www.ncbi.nlm.nih.gov/pubmed/25173340?tool=bestpractice.com ​ In 2020, the Society for Vascular Surgery and Society of Thoracic Surgeons proposed that aortic dissection <24 hours since first onset of symptoms should be classified as hyperacute (<24 hours).[3]Lombardi JV, Hughes GC, Appoo JJ, et al. Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) reporting standards for type B aortic dissections. J Vasc Surg. 2020 Mar;71(3):723-47. http://www.ncbi.nlm.nih.gov/pubmed/32001058?tool=bestpractice.com ​