Aortic Dissection


Dissection results from a tear in the aortic intima, which cleaves a plane in the media and allows blood to enter the false lumen. Arterial pressure extends the dissection for a variable distance distally and sometimes proximally.


  • Chest pain (sudden onset, "ripping"). May also have myocardial ischaemia pain if involving coronaries. May radiate to back
  • Painless in 10%
  • Neurological symptoms (radicular pain / stroke), syncope, limb pain, dysphagia
  • Symptoms of organ / limb ischaemia
Aortic Dissection 9 Months Earlier - Normal Aortic Dissection at Presentation Dissection Stanford B. Three dimensional reconstruction from the computed tomography angiogram showing the aortic arch and the iliac bifurcation. The left arrow shows the intimal flap and the right arrow indicates the occluded left commom iliac artery Iomhar DEBakey and Stanford Classifications


Stanford type A dissection

  • Involves the ascending aorta
  • 75% of all cases of dissection
  • Presents with anterior chest pain
  • Treatment = emergency cardiothoracic surgery
    • Mortality 50% if no treatment
    • Cardiac tamponade
    • Aortic rupture
    • AMI, aortic regurgitation if involves aortic root

Stanford type B dissection

  • Starts distal to the left subclavian artery
  • Presents with inter-scapular back pain (ripping)
  • Divided clinically into uncomplicated and complicated (20%)
  • Complications:
    • Organ ischaemia (flap occluding vessel)
      • Renal, splenic, mesenteric, spinal infarction
    • Later aneurysmal dilatation of the aorta (20%

Treatment type A

  • Surgery - open resection & replacement aortic segment
  • Surgical mortality 30%
  • High rate complications (organ/limb/spinal/brain ischaemia)

Treatment type B

  • Uncomplicated dissections treated medically
  • Control hypertension - analgesia, β block ±nitrates
  • Complicated dissections require surgery

Summary of Systematic Review

A normal D-dimer excludes acute aortic dissection.[Eur Heart J. 2007 Dec;28(24):3067-75]. PMID: 17986466.

  • 16 studies (437 patients), >D-dimer:
    • High sensitivity (0.97 95% CI 0.94-0.98)
    • High neg LR (0.06 95% CI 0.02-0.13)
  • A negative D-dimer will exclude AAD

Content by Dr Gerry McCarthy, Dr Íomhar O' Sullivan. Last review Dr ÍOS March 24, 2024.