Between which two layers of the aorta does blood go between in an aortic dissection?
Tunica intima and tunica media
What is an aortic dissection?
- Tear in aortic wall tunica intima allows blood to split intima from media, causing branches of the aorta to occlude sequentially
- Acute vascular involvement
What are the two types of aortic dissection?
1) Type A (70%) - ascending aorta involvement
2) Type B (30%) - no ascending aorta involvement
What are risk factors for aortic dissection?
- HTN
- Atherosclerosis
- Aortic aneurysm
- Connective tissue disorders i.e. Marfan’s, Ehlers-Danlos
What is the key symptom of aortic dissection?
Sudden onset chest pain
- Tearing
- Radiating to the back
What are other potential symptoms of aortic dissection?
- Acute limb ischaemia
- Hemi/paraplegia
- Unequal arm pulses/BP
- Anuria
What are complications of aortic dissection?
- Aortic regurgitation
- Inferior MI
- Cardiac arrest
How do you diagnose aortic dissection?
- CT angiogram
- Transoesophageal echo
- MR angiography
What other investigations might you do in someone presenting with aortic dissection?
ECG, CXR, troponin
How do you immediately manage a patient with aortic dissection?
- ATLS
- Beta blocker e.g. labetalol or CCB
- Opioid analgesia
How do you definitively treat all type A aortic dissections?
Open surgery
How do you treat some type B aortic dissections?
Open surgery or endovascular stent-graft
What medication should people be put on post aortic dissection?
Anti-HTN
What is an arterial aneurysm?
Dilation of artery > 50% diameter, involving all layers of the wall
What is the diameter of an (unruptured) AAA?
> 3cm across
What are causes of AAA?
- Atheroma
- Trauma
- Infection
- Connective tissue disorders i.e. Marfan’s, Ehlers-Danlos
- Inflammatory (Takayasu’s aortitis)
What are the symptoms of an unruptured AAA?
- Asymptomatic
- Abdo/back pain
What are symptoms of a ruptured AAA?
- Abdo pain radiating to back/iliac fossa/groin
- Syncope/collapse
- Expansile abdo mass
What are complications of a ruptured AAA?
- Shock
- Thrombosis + emboli
- Pressure on other structures
How is screening carried out for AAA?
All men at aged 65 are invited for screening to reduce mortality from ruptured AAA
How is an unruptured AAA diagnosed/monitored?
- Clinical
- O/E - expansile abdo mass
- Abdo US ± CT/MRA
How is a ruptured AAA diagnosed?
Clinical
How do you treat unruptured AAA?
- Monitoring
- RF modification
- Elective surgery if diameter >5.5cm OR EVAR stenting
How do you treat a ruptured AAA?
- Refer to vascular surgeon and anaesthetist
- ECG, bloods (amylase, Hb, crossmatch), catheterise bladder
- Treat shock with O rhesus negative blood if not cross matched - keep systolic < 100mmHg to avoid rupturing a contained leak (raised BP is common early on)
- Prophylactic antibiotics e.g. co-amoxiclav IV 625mg
- Surgery
