Aneurysms Flashcards
What is a pseudoaneurysm and how do they form?
Breach to arterial wall so accumulation of blood between tunica media and tunica adventitia
Usually after damage to vessel wall (e.g following cardiac catheterisation, IVDU, inflammation or vasculitis)
Most common in femoral artery, but can occur in radial, carotid, abdominal/thoracic aorta
What is a vascular complication of acute pancreatitis?
Splenic pseudoaneurysm
What are the clinical features of a pseudoaneurysm?
- Pulsatile lump that is tender and painful
- Could be limb ischaemia due to distal arterial occlusion by compression so check pulses
- If infected will be erythematous, tender and purulent material may be discharging
If a patient reports they have had a bleed from a pseudoaneurysm but it has stopped now, what should you do?
Close monitoring as could represent a Herald Bleed so could rebleed at any time
How are pseudoaneuryms diagnosed an assessed?
- Gold standard: Duplex US which will show turbulent back and forward flow (yin-yang sign).
- Can do CT if cannot access with US
- Routine bloods (FBC, CRP, U+Es, clotting, crossmatch due to risk of rupture)
- Blood cultures and Pus MC+S if discharging
How are small and large non-infected pseudoaneurysms managed?
Small: often left alone as can thrombose and close off, however some continue to grow until perforate
Large:
Ultrasound guided compression (can be painful and needs 30 mins direct compression)
OR ultrasound guided thrombin injection (follow up imaging to check resolution)
OR endovascular stenting
OR surgical repair/ligation
Why is endovascular stenting and surgical repair of pseudoaneurysms more complication?
Endovascular stenting: sometimes insufficient space to put stent without covering a major branch, can leak so pseudoaneurysm still perfused, can migrate
Surgical repair/Ligation: need healthy proximal and distal artery, ligation can sometimes cause distal ischaemia so will need bypass graft
How are infected psuedoaneurysms managed? (usually from IVDU)
- More likely to become septic or rupture so need urgent treatment
- If any discharge pressure dressing and urgent imaging
- Surgical ligation, sometimes requiring bypass graft due to acute limb ischaemia but be careful as graft can become infection
- Small risk of amputation even with collateral blood supply
What are some risk factors for peripheral and visceral aneurysms?
- Smoking
- Hyperlipiadaemia
- HTN
- FHx
- Marfan’s
- Takayasu’s aortitis
Aneurysms are persisitent abnormal dilatations of an artery above 1.5X the normal diameter
What vessels are classed as visceral aneurysms?
- Splenic (most common)
- Hepatic (second most common)
- Renal
- Intestinal arteries
- Mesenteric arteries
How are peripheral and visceral aneurysms investigated and managed in general terms?
Ix:
- CT angiography or MRA if renal issues
- US duplex scans for detection or follow up
Mx
- Watchful waiting whilst optimising CVS factors so antiplatelet and statin therapy
- Surgical intervention (endovascular or open)
What are the most common peripheral artery aneurysms?
- Popliteal (high risk of embolisation and/or occlusion)
- Femoral
Popliteal aneurysms are the most common peripheral aneurysm. How do they present?
- Acute limb ischaemia (aneurysm thrombosis or emboli) OR
- Intermitten claudication
Can also be found incidentally during AAA work up or during TKR or from compression symptoms on popliteal vein or peritoneal nerve
How are suspected popliteal aneurysms investigation?
- Initially US duplex to rule out other popliteal swellings e.g Baker’s cyst, lymphadenopathy
- CT angiogram or MRA
How are popliteal aneurysms managed?
If symptomatic or asymptomatic and over 2.5cm should be given treatment
- If thrombosis in tibial vessel then embolectomy or thrombolysis
- Endovascular: stent insertion
- Open: ligation of aneurysm or resection with bypass graft
What are the causes of femoral pseudoaneurysms?
- Patient self-injecting e.g IVDU
- Percutaenous vascular interventions
How do femoral pseudoaneurysms present, and how are they investigated and managed?
Presentation
- Symptoms due to thrombosis, rupture, embolisation or infecton
- Varying degrees of claudication or acute limb ischaemia
Ix
- US duplex then CT angiogram or mra
Mx
- Open surgical repair
What are some risk factors for splenic pseudoaneurysms and how do they present?
Risk factors: female, multiple pregnancies, portal hypertension, acute pancreatitis, pancreatic pseudocysts
Presentation: vague epigastric or LUQ pain, if ruptured then severe abdominal pain
How are splenic and hepatic psuedoaneurysms investigated and managed?
Ix: CT angiography or MRA
Mx: 1st Line is endovascular repair wirh embolisation or stent graft once patient haemodynamically stable
What is the cause of hepatic pseudoaneurysms and how do they present?
Causes: percutaneous instrumentation, trauma, degenerative disease, post liver transplant around vessel anastomoses
Presentation: usually asymptomatic but can have vague RUQ/Epigastric pain and jaundice if biliary obstruction
How do renal artery pseudoaneurysms present, and how are they investigated and managed?
Presentation: often incidental finding/asymptomatic but can have haematuria, resistant hypertension or loin pain if renal infarction
Ix: CT angiogram or MRA
Mx: Endovascular repair with stent if affecting renal artery, or coils if affecting hilum. Can also do renal transplant rarely
