Aortic dissection Flashcards
define aortic dissection?
a condition where a tear in theaortic intimaallows blood to surge into the aortic wall, causing a split between the inner and outer tunica media, creating afalse lumen
how to classify aortic dissection?
- ascending aortic dissection (this is common)
- descending aortic dissection
what is the aetiology of an aortic dissection?
- aortic dissections are preceded by degenerative changes in the smooth muscle of the aortic media
what are common risk factors for an aortic dissection?
- hypertension
- aortic atherosclerosis
- connective tissue disease eg. marfans
- congenital cardiac abnormalities
- iatrogenic causes (angiography)
- trauma
- crack cocaine
what is a dangerous effect of aortic dissection?
- the expansion of the false lumen might result in obstruction of the subclavian, carotid, coeliac and renal arteries.
what is the main presenting complaint of aortic dissection?
- sudden central tearing pain radiating to the back in between the shoulder blades.
what are the other symptoms of aortic dissection if it obstructs other branches of the aorta?
- carotid artery: hemiparesis, dysphasia, blackout
- coronary artery: chest pain
- subclavian artery : ataxia, loss of consciousness
- anterior spinal artery: paraplegia
- coeliac artery : severe abdominal pain
- renal artery :anuria, renal failure
how to recognise aortic dissection on physical examination?
- murmur on the back
- hypertension
- blood pressure difference between the arms is more than 20mmHg
- wide pulse pressure
- unequal arm pulses
- there could be a palpable abdominal mass
- there might be signs of aortic regurgitation
what might hypotension in aortic dissection suggest?
this suggests cardiac tamponade
what is pulsus paradoxus?
abnormally large decrease insystolic blood pressureandpulse wave amplitudeduringinspiration
what might pulsus paradoxus indicate?
- tamponade
- pericarditis
- chronic sleep apnoea
- obstructive lung disease
what are the appropriate investigations for aortic dissection?
- bloods
- chest xray
- ECG
- CT thorax
- echo
- Cardiac catheterisation and aortography
what bloods should be taken for aortic dissection?
- FBC
- x-match 10 units of blood
- Us and Es
- clotting screen
what might be seen on a chest x-ray of aortic dissection?
- widened mediastinum
what might be seen on a ECG of aortic dissection?
- its often normal
- if the ostia is damaged you might get
- left ventricular hypertrophy or inferior MI