Vascular Flashcards
At what diameter do we consider someone to have a AAA?
> 3cm
What are risk factors for AAA?
Most common:
Smoking
HTN
Diabetes
Rarer:
Syphilis
Ehlers Danlos type 1
Marfans
What is the difference between true and false AAAs?
True AAA involves all 3 layers of arterial wall
False only involves a siingle layer of fibrous tissue
What demographic is most likely to have a true AAA?
Elderly men
As such, screening via US is being offered to all men aged 65
Where does the aneurysm in AAA usually rupture?
80% into retroperitoneal space
20% rupture anteriorly
What impacts the risk of rupture with AAA?
Size of aneurysm:
2% of 4cm aneurysms will rupture over 5 years compared with 75% of 7cm aneurysms
What are indications for surgery in AAA?
> 5.5cm
Symptomatic
Rupture
Outcomes of AAA screening?
<3cm - no further action
3-4.4cm - small aneurysm, scan 12 monthly
4.5-5.4 - rescan 3 monthly
>5.5 - refer within 2 weeks to vascular surgery for probable intervention
Management of AAA if <5.5cm?
Abdominal US surveillance and optimise risk factors (e.g. smoking, HTN), commence aspirin/statin therapy
Management of AAA if >5.5cm?
Elective endovascular repair (EVAR)
This involves placing a stent into the abdominal aorta via the femoral artery to prevent blood collecting in the aneurysm
Open repair (clamping the aorta, then replacing it with a prosthetic graft)
If aneurysm >6.5 must also inform DVLA until repaired (disqual. from driving)
Symptoms of AAA?
Abdominal pain
Back/loin pain
Distal embolisation producing limb ischaemia
Signs:
Pulsatile mass felt in abdomen
Other than US, what other imaging would you like in AAA?
CT scan with contrast to help plan surgery
Main complication of EVAR?
Endovascular leaking (blood leaks out of the graft, allowing for aneurysm to still collect blood)
How to treat ruptured AAA?
High flow O2 IV access Urgent bloods, crossmatch Maintain BP <100 (risk of dislodging clot precipitating further bleeding) Open surgical repair
Where do thoracic aortic aneurysms affect?
60% ascending/aortic root
10% aortic arch
40% descending aorta
(This doesn’t add up but.. maybe 2 places affected at once?)
What are thoracic aortic aneurysms due to?
Degradation of the tunica media (middle layer of artery/vein)
What are the main causes of thoracic aortic aneurysms?
Connective tissue diseases (Marfan’s, Ehler’s danlos)
Bicuspid aortic valve
Trauma
Aortic dissection
Aortic arteritis (e.g. Takayasu arteritis)
Tertiary syphilis
What are the risk factors for thoracic aortic aneurysm?
FHx HTN Atherosclerosis Smoking High BMI Male Age (advanced)
Clinical features of thoracic aortic aneurysm?
Usually asymptomatic Pain: Asc. aorta - ant. chest Aortic arch - neck Desc. aorta - between scapulae
What do you see on CXR with thoracic aortic aneurysm?
Widened mediastinal silhouette and an enlarged aortic knob
What is the imaging of choice in thoracic aortic aneurysm?
CT chest with contrast
Management of thoracic aortic aneurysm?
Statin + antiplatelet (aspirin)
BP management
Smoking cessation
Surgery:
Usually if >5.5cm
What are the layers of an artery?
Tunica intima (inner) Tunica media (middle) Tunica adventitia (outer)
What is an aortic dissection?
A tear in the intimal layer of the aortic wall causing blood to flow between and split apart the intima and media
How can we define aortic dissection?
Acute <14 days
Chronic >14 days
What are the directions an aortic dissection can progress?
Toward the iliac arteries (anterograde dissection)
Toward the aortic valve (retrograde dissection)
What classifications can we use for aortic dissection?
Stanford or DeBakey classifications
Risk factors of aortic dissection?
HTN Atherosclerotic disease Male Connective tissue disorders (Ehler's Danlos type 1 or Marfan's) Bicuspid aortic valve
Clinical features of aortic dissection?
Tearing chest pain
Radiates to the back
Signs:
Tachycardia
Hypotension
New aortic regurg. murmur
What investigations would you like for aortic dissection?
Baseline bloods - FBC, U+Es, LFTs, troponin, coagulation
Crossmatch of at least 4 units
ABG
ECG
Imaging:
CT angiogram
Transoesophogeal echo
How do we manage aortic dissection?
ABCDE + Resus.
Stanford type A: Managed surgically (replacement of aorta with synth. graft)
Stanford type B:
If uncomplicated, manage medically (beta blockers first line [labetalol], calc. channel blockers second line)
What is Stanford type A and Stanford type B?
A involves ascending aorta (includes DeBakey type I + II)
B does not involve ascending aorta (DeBakey type III)
What is chronic limb ischaemia?
PAD that results in symptomatic reduced blood supply to the limbs
What causes chronic limb ischaemia?
Atherosclerosis
Vasculitis (rarely)
What are the risk factors for chronic limb ischaemia?
Smoking DM HTN Hyperlipidaemia Increasing age FHx Obesity/physical inactivity
What are the 4 stages of chronic limb ischaemia?
Stage I - Asymptomatic
Stage II - Intermittent claudication
Stage III - Ischaemic rest pain
Stage IV - Ulceration or gangrene, or both
What is Buerger’s test?
The patient lies supine and raises their legs until they go pale. They then slowly lower their legs until the point where their legs regain colour.
The point at which they lose colour is known as Buerger’s angle
What is critical limb ischaemia?
An advanced form of chronic limb ischaemia. It can be defined in 3 ways:
Ischaemic rest pain for greater than 2 weeks duration
Presence of ischaemic lesions or gangrene
ABPI less than 0.5
What are the main differentials for limb ischaemia?
Spinal stenosis (neurogenic claudication) Acute limb ischaemia
What are the features of spinal stenosis?
Typically pain from the back radiating down the lateral aspect of the leg. There are often symptoms on initial movement/symptoms that are relieved by sitting rather than standing
Positional pain is the main thing that differentiates this from claudication
How does acute limb ischaemia present?
Sudden onset of the 6 P symptoms
How do we manage spinal stenosis?
Laminectomy
Acute limb ischaemia features?
Less than 2 weeks of clinical features
Features include: Pale Pulseless Painful Paralysed Paraesthetic Perishing with cold
How do we diagnose chronic limb ischaemia?
Clinically
How do we confirm the diagnosis/severity of chronic limb ischaemnia?
Ankle-brachial pressure index (ABPI) Normal >0.9 Mild 0.8-0.9 Moderate 0.5-0.8 Severe <0.5
How do we investigate critical limb ischaemia?
Doppler ultrasound to investigate the severity and anatomical location of any occlusion
Patients can also maybe have a CT angiography
Also a cardiovascular risk assessment because of the high likelihood of CVS risk factors
How do we manage chronic limb ischaemia?
Lifestyle advice (smoking cessation, regular exercise, weight reduction) Statin therapy (atorvastatin 80mg OD) Anti-platelet therapy (clopidogrel 75mg OD) Optimise diabetes control
Surgery
How do we manage critical limb ischaemia?
Urgent referral for surgery
Angioplasty (with or without stenting)
Bypass grafting (diffuse disease/younger patients)
Amputation
What are the complications of chronic limb ischaemia?
Sepsis (secondary to infected gangrene)
Acute-on-chronic ischaemia
Amputation
Reduced mobility/QoL
What is acute limb ischaemia?
Sudden decrease in limb perfusion that threatens the viability of the limb
What causes acute limb ischaemia?
Embolisation
Thrombosis in situ
Trauma (including compartment syndrome)
If someone presents without any risk factors for PVD and is younger than 50, what tests should be done?
Thrombophilia screen
Homocysteine (high levels can cause disease)
If one leg is completely fine (pulses etc.) but the other is showing signs of acute limb ischaemia, what is the likely cause?
Embolic occlusion
What should you establish in your history if patient presents with acute limb ischaemia?
Potential causes of embolisation (chronic limb ischaemia, AF, MI, AAA, peripheral aneurysms)
How do you investigate suspected acute limb ischaemia?
Bloods, including serum lactate
Thrombophilia screen
ECG
Doppler ultrasound (both limbs) CT angiography
How concerned are we about acute limb ischaemia?
Surgical emergency - complete art. occlusion can cause irreversible tissue damage within 6 hours
What is the initial management of acute limb ischaemia?
Refer to senior surgical
High flow O2
IV access
Heparin bolus/treatment dose
When do we offer conservative management in acute limb ischaemia?
Rutherford 1 and 2a
What is the conservative management of acute limb ischaemia?
Prolonged course of heparin
Regular APTT monitoring and clinical review
When do we surgical intervention in acute limb ischaemia?
Rutherford 2b
How do we treat acute limb ischaemia surgically?
If embolic:
Embolectomy
Thrombolysis
Bypass surgery
If thrombotic:
Thrombolysis
Angioplasty
Bypass surgery
What indicates amputation in acute limb ischaemia?
Irreversible limb ischaemia (mottled non-blanching appearance with hard woody muscles)
What indicates a need for amputation in acute limb ischaemia?
Irreversible limb ischaemia (mottled non-blanching appearance with hard woody muscles)
What is the long term management for patients who have had an acute limb ischaemia?
Managing the cardiovascular mortality risk:
Smoking cessation
Weight loss
Increase in exercise
Often started on an antiplatelet such as aspirin or clopidogrel as well
What is an important complication of acute limb ischaemia?
Reperfusion injury resulting in: Compartment syndrome Release of substances from the damaged muscle cells, e.g. - K+ ions H+ ions Myoglobin (resulting in AKI)
What is chronic mesenteric ischaemia?
Reduced blood supply to the bowel which gradually deteriorates over time as a result of atherosclerosis in the coeliac trunk, SMA or IMA
What are the clinical features of chronic mesenteric ischaemia?
Postprandial pain (10 mins-4 hours after eating) Weight loss (decreased calorie intake/malabsorption) Concurrent vascular comorbidities
What is the diagnostic test of choice in chronic mesenteric ischaemia?
CT angiography
How do we manage chronic mesenteric ischaemia?
Modify risk factors
Anti-platelet/statin
Endovascular/open procedures (angioplasty + stenting/endarctectomy or bypass)
What are the complications of chronic mesenteric ischaemia?
Bowel infarction
Malabsorption
What is acute mesenteric ischaemia?
Sudden decrease in blood supply to the bowel, resultiing in bowel ischaemia and if not promptly treated, gangrene and death
What are the causes of acute mesenteric ischaemia?
Thrombus in situ (25%)
Embolism (50%)
Non-occlusive cause (20%)
Venous occlusion and congestion (10%)
What are the clinical features of acute mesenteric ischaemia?
Generalised abdominal pain, out of proportion to clinical findings
Nausea, vomiting (75%)
Investigations for acute mesenteric ischaemia?
ABG - serum lactate/acidosis
Routine blood tests
Imaging:
CT scan with IV contrast
What will acute mesenteric ischaemia show on CT scan?
Arterial bowel ischaemia will show:
Oedematous bowel (secondary to ischaemia + vasodilation)
Loss of bowel wall enhancement
Pneumatosis
Management of acute mesenteric ischaemia?
Resuscitation Senior involvement Broad spectrum abx Catheter + fluid balance chart Excision of necrotic or non-viable bowel Revascularisation of the bowel
What are the complications of acute mesenteric ischaemia?
Bowel necrosis
Perforation
Mortality rate of 50%
What do you need to rule out in hyperhidrosis?
Secondary causes: Pregnancy/menopause Anxiety Infection Malignancy Endocrine disorders Medications
What causes deep venous insuffiency?
DVT/Valvular insufficiency
Caused by failure of the venous system
Risk factors for deep venous insufficiency?
Female gender Pregnancy Increasing age Previous DVT/phlebitis Obesity Smoking
Clinical features of deep venous insufficiency
Chronically swollen lower limbs Pruritic, painful and aching lower limbs Varicose eczema Thrombophlebitis Haemosiderin skin staining Lipodermatosclerosis Atrophie blanche
How do we investigate deep venous insufficiency?
Doppler ultrasound scan
Routine blood tests to assess other aetiologies
Documentation of foot pulses/ABPI to assess viability of compression therapy
How do we manage deep venous insufficiency?
Conservative:
Compression stockings
Analgesia
Surgical:
If post DVT/thrombotic type syndrome you can do venous stenting
Complications of DVI?
Swelling Recurrent cellulitis Chronic pain Ulceration DVT
What are varicose veins?
Tortuous dilated segments of veins associated with valvular incompetence
What are the four major risk factors for development of varicose veins?
Prolonged standing
Obesity
Pregnancy
Family history
Clinical features of varicose veins
Unsightly veins
Pain/aching/swelling/itching
Variscosities in the course of the great/short saphenous veins
Features of venous insufficiency
What classification do we use for varicose veins?
CEAP classification
Investigations for varicose veins?
Duplex ultrasound
Conservative management of varicose veins
Education - avoid prolonged standing, weight loss, increase exercise
Compression stockings* (if interventional treatment is not appropriate)
Surgical treatment of varicose veins
Vein ligation, stripping and avulsion
Foam sclerotherapy
Thermal ablation
Complications of varicose veins
Surgical complications: Haemorrhage Thrombophlebitis DVT Disease recurrence Nerve damage
What type of ulcer is most common?
Venous (80%)
Remaining 20% are arterial and neuropathic
Features of a venous ulcer
Painful Shallow Irregular border Granulating base Gaiter region of legs Varicose eczema Thrombophlebitis Haemosiderin skin staining Lipodermatosclerosis Atrophie blanche
Investigations in venous ulcers
Usually a clinical diagnosis
Can confirm underlying venous insufficiency with duplex ultrasound
ABPI to assess for any arterial component
Swab cultures if suspecting infection
Management of venous ulcers
Conservative: Leg elevation Increased exercise Lifestyle changes Weight reduction *Multicomponent compression bandaging
If varicose veins also present, endovenous techniques or open surgery
Features of an arterial ulcer
Small deep lesions Well defined borders Necrotic base Pressure areas/sites of trauma Usually a history of intermittent claudication/critical limb ischaemia Painful Cold Absent pulses
Investigating arterial ulcers
ABPI: >0.9 normal 0.8-0.9 mild 0.5-0.8 moderate <0.5 severe
Management of arterial ulcers
Conservative:
Lifestyle changes
Medical:
Aspirin/clopidogrel
Surgical:
Angioplasty
Bypass grafting
Neuropathic ulcer features
Painless ulcers at pressure points History of peripheral neuropathy Burning/tingling in the legs Wasting of muscles Punched out appearance Glove/stocking distribution Pulses present
Investigations for a neuropathic ulcer
Blood glucose levels
Serum B12 levels
ABPI +/- duplex (for concurrent arterial disease)
Check the extent of peripheral neuropathy with touch test/vibration test
Management of neuropathic ulcer
Diabetic foot clinic
Manage diabetes
What is Charcot’s foot?
A neuroarthropathy whereby a loss of joint sensation results in continual unnoticed trauma/deformity occurring
Can predispose patients to neuropathic ulcer formation
