4th June 2026

Diagnosis

History 

Typically, an aortic dissection presents with sudden onset of ‘tearing’ abdominal, back or chest pain. However, we must be aware of atypical symptoms as these can often lead to a missed diagnosis, and if no treatment is provided within 48 hours of initial symptom onset, then mortality rates reach up to 50%.

Key diagnostic features

• Sudden onset severe chest pain/ retrosternal (anterior dissection) / interscapular (descending aorta) or lower back pain – described as ‘sharp’ or ‘tearing’ and is a maximal pain level at onset. 
• Sudden onset abdominal pain – can occur with dissection; however, more likely to be a ruptured AAA
• Radiation of the pain to the jaw, neck or throat 
• Pain that migrates (highly specific for AAD) – starts where the initial tear is present and is associated with where the tear continues to e.g: starting in the back and moving to the legs, may be due to common iliac or external iliac involvement.
• Pain that stops quickly – If the process halts or if a re-entry tear is created into the true lumen.
• Some patients (5-15%) present with no pain! (see points below)
• Syncope – If a patient presents with syncope, they may not feel the initial pain associated with the tear
• Seizures
• Stroke – As the primary tear occurs, there is instantaneous neurological deficit, so no pain is felt. It is important to consider if a patient becomes dysphasic, they won’t be able to highlight pain.
• Dyspnoea
• Haemoptysis
• Altered mental status 
• Paraplegia/ limb paraesthesia – typically painless due to occlusion of the origin of spinal arteries 
• Limb pain or weakness
• Flank pain

*Consider an acute aortic dissection if symptoms include chest/back pain AND new or evolving neurological deficit.

Key examination features

An A-E examination must be undertaken, including a full cardiovascular and abdominal examination. 

Measuring blood pressure in both upper limbs should be performed if AAD is suspected. 

• Hypertension 
• Asymmetrical pulses and readings of blood pressure – A difference of >20mmHg between each limb 
• Aortic regurgitation 
• Shock – hypovolaemia, tamponade 
• Acute abdomen symptoms (if mesenteric/coeliac artery affected) 
• Acute heart failure symptoms – caused by sudden aortic annular dilatation with acute aortic regurgitation (severe) or dissection of the coronary artery with vessel occlusion leading to shock (Cardiogenic).
• Neurological deficits – reduced power/weakness in limbs, paraesthesia, Horner’s syndrome 
• Haemothorax

Constellations of symptoms may suggest the following: 

• Haemopericardium: Absent or faint heart sounds, pulsus paradoxus, distended neck veins and the presence of shock.
• Branch vessel occlusion: Weak central or peripheral pulse unilaterally, >20mmHg difference in BP in each arm, bruit or palpable thrill over any pulse or the abdominal aorta, neurological deficit or stroke features
• Aortic dilatation: Diastolic murmur heard over aortic valve area, a wide pulse pressure –