Peripheral vascular disease (CV) Flashcards
Define peripheral artery disease.
Disease characterised by narrowing and occlusion of the peripheral arteries due to atherosclerotic plaques
Includes a range of arterial syndromes caused by atherosclerotic obstruction of lower-extremity arteries
What is peripheral artery disease most commonly caused by?
Atherosclerosis
What classification system is used for peripheral artery disease?
Fontaine classification
What are the stages of the Fontaine classification of peripheral artery disease?
- stage I - asymptomatic PAD
- stage II - pain (intermittent claudication) on exertion:
- IIa - claudication at walking distance >200m
- IIb - claudication at walking distance <200m
- stage III - ischaemic pain at rest
- stage IV - necrosis, ulcers or gangrene (dry or wet)
What is claudication (peripheral artery disease)?
Pain on exertion due to inadequate flow during exercise, causing fatigue, discomfort or pain
What is acute limb ischaemia (PAD)?
Sudden decrease in limb perfusion that threatens limb viability
What are the 6Ps of acute limb ischaemia (PAD)?
- Pain
- Paralysis
- Paraesthesia
- Pulseless
- Pallor
- Perishingly cold
What is a major risk factor for acute limb ischaemia (PAD)?
Atrial fibrillation
What are the two key causes of acute limb ischaemia (PAD)?
- atrial fibrillation
- atherosclerotic plaque
What two types of causes can acute limb ischaemia (PAD) have?
- thrombotic causes (pre-existing claudication with sudden deterioration, reduced/absent pulses in contralateral limb)
- embolic causes (sudden onset painful leg, Hx shows obvious cause of embolus e.g. AF, recent MI, no evidence of PVD)
How is acute limb ischaemia (PAD) treated?
IV heparin (medical emergency requiring revascularisation within 4-6h to save limb)
What are some examples of chronic limb ischaemia (PAD)? (4)
- intermittent claudication
- Buerger’s disease
- Leriche syndrome
- critical limb ischaemia
What is intermittent claudication (PAD)?
- calf pain on exercise
- exercise increases muscle demand = cannot be met by supply
- improvement occurs by maintaining exercise –> stimulate angiogenesis
What is Buerger’s disease (thromboangiitis obliterans) - PAD?
- happens in young male smokers with symptoms similar to limb ischaemia
- paraesthesia/cold sensation in fingers or limbs
- Raynaud’s phenomenon
What is Leriche syndrome (PAD)?
Aortoiliac occlusive disease
Symptoms:
- buttock claudication
- impotence
- absent/weak distal pulses
What is the most severe manifestation of peripheral vascular disease?
Critical limb ischaemia
What is critical limb ischaemia (PAD)?
- compromise of blood flow to an extremity, causing chronic limb pain at rest (worse at night) for 2+ weeks
- pain at rest
- can lead to tissue loss: gangrene, arterial ulcers
- most severe form of PAD
What are the general clinical features of PAD? (4)
- most patients are asymptomatic
- diminished/absent pulse
- erectile dysfunction (impotence)
- thigh or buttock pain (claudication) when walking
What artery is affected in calf pain (PAD)?
Femoral artery
What artery is affected in buttock pain (PAD)?
Iliac artery
What are the clinical features of intermittent claudication (PAD)?
- cramping pain of leg (calf, thigh or buttock) which is worse on exertion/walking a given distance (claudication distance)
- relieved by rest
- calf claudication = FEMORAL disease
- buttock claudication = ILIAC disease
What are the red flag signs of PAD that are indicative of critical limb ischaemia? (2)
- resting pain
- skin changes - ulcers or gangrene
What are the clinical features of critical limb ischaemia (PAD)? (5)
- pain at rest
- ulcers
- gangrene
- night pain (relieved by dangling leg over edge of bed)
- muscular atrophy
What are the clinical features of Buerger’s disease (PAD)? (2)
- paraesthesia/cold sensation in fingers or limbs
- Raynaud’s phenomenon
What are the clinical features of Leriche syndrome (aortoiliac occlusive disease)? (3)
- buttock claudication
- impotence (erectile dysfunction)
- absent/weak distal pulses
What might you find on examination in acute limb ischaemia (PAD)? (6 + 5)
- Pain
- Paralysis
- Paraesthesia
- Pulseless
- Pallor
- Perishingly cold
- other symptoms:
- atrophic skin (shiny/scaly)
- hairless
- punched-out ulcers (painful)
- thickened toenails
- colour change when raising leg (to Buerger’s angle) - dependent rubor
What are the risk factors for PAD? (8)
- smoking
- diabetes
- hypertension
- hyperlipidaemia
- age>40
- Hx CAD/cerebrovascular disease
- physical inactivity
- renal failure
What is the first-line investigation for PAD?
Ankle-brachial pressure index (ABPI)
What is ABPI (PAD)?
Ratio of systolic ankle BP to systolic brachial BP (marker of cardiovascular disease)
Ankle SBP / Brachial SBP
What ABPI indicates PAD?
<0.8 (0.5-0.9)
What is important to remember if ABPI<0.8 in PAD?
Do NOT apply a pressure bandage as this will worsen ischaemia
What ABPI indicates critical limb ischaemia?
<0.5
What are the ABPI cut-offs for normal/PAD? (4)
- arterial calcification: >1.2
- normal: 0.9-1.2
- PAD: 0.5-0.9
- critical limb ischaemia: <0.5
What do you need to keep in mind when using ABPI to measure PAD?
Calcification of arteries can occur in diabetes and renal failure, which can alter results and cause high ankle pressures due to incompressible arteries
When is ABPI not useful in PAD?
In an emergency when a patient presents with acute limb ischaemia, as it does not identify the site of arterial occlusion and would not guide acute management
What is the first-line investigation for intermittent claudication?
Duplex ultrasound - can determine site, severity and length of stenosis
What is the first-line investigation for patients with suspected acute limb ischaemia (PAD)?
Bedside handheld doppler scan - absent/reduced signal in acute limb ischaemia
Followed by lower limb CT angiography to quantify extent of occlusion
What investigation is important to do in all patients presenting with suspected acute limb ischaemia (think 6Ps)?
Handheld doppler USS (absent/reduced signal) - as ABPI not helpful in acute setting
What is the gold-standard investigation for PAD?
MRI/CT angiogram
What is Buerger’s test (PAD)?
- lie patient flat on bed and lift leg to 45 degrees
- limb developing pallor indicates arterial insufficiency
- angle <20 degrees indicates severe limb ischaemia
- when patient swings leg over bed, reactive hyperaemia is seen
What are some differential diagnoses for PAD? (7)
- spinal stenosis (ABPI normal)
- arthritis
- venous claudication (ABPI normal)
- chronic compartment syndrome (athletes, duplex USS shows no stenosis)
- symptomatic Baker’s cyst (ABPI normal, cystic mass in popliteal fossa)
- nerve root compression
- Buerger’s disease (non-atherosclerotic vasculitis, paraesthesia/cold sensation in fingers or limbs, Raynaud’s, rest pain and ulceration/gangrene, young male smokers)
What classification is used to stage peripheral vascular disease?
Fontaine classification:
- I: asymptomatic
- II: intermittent claudication
- III: rest pain
- IV: ulceration/gangrene/necrosis (tissue loss)
What is the management plan for intermittent claudication? (5)
- antiplatelet therapy (clopidogrel/aspirin)
- exercise
- risk factor modification
- hypertension with ACEi
- dyslipidaemia with statin
- beta-blockers
- symptom relief (cilostazol or naftidrofuryl)
- consider revascularisation
What is the Rutherford classification for PAD?
- 0: asymptomatic
- 1: mild claudication
- 2: moderate claudication
- 3: severe claudication
- 4: ischaemic rest pain
- 5: minor tissue loss (non-healing ulcer, focal gangrene with diffuse pedal ischaemia)
- 6: major tissue loss (extending above transmetatarsal level, frank gangrene)
What doses of antiplatelet therapy & statins are given in PAD?
- clopidogrel 75mg OD
- atorvastatin 80mg OD (as secondary prevention, 20mg as primary prevention)
What can we give for intermittent claudication if exercise is ineffective and patient does not want to be referred for angioplasty/bypass surgery?
Naftidrofuryl oxalate - vasodilator that can alleviate pain in PAD
What do we do if risk factor modification and exercise have not improved symptoms in intermittent claudication?
Refer for surgical revascularisation
What is the management plan for critical limb ischaemia (PAD)? (6)
- urgent referral to vascular MDT for revascularisation (endovascular vs surgical)
- antiplatelet therapy (aspirin/clopidogrel 75mg OD)
- risk factor modification
- spinal cord stimulation (if inoperable)
- autologous bone marrow stem cell transplantation
- consider amputation
What is the difference between endovascular and surgical revascularisation in critical limb ischaemia?
- endovascular revascularisation (angioplasty +/- stent, atherectomy): stenosis<10cm / chronic occlusions <5cm
- surgical revascularisation (bypass with autologous vein/prosthetic material): stenosis>10cm / chronic occlusion >5cm
What is the last resort for critical limb ischaemia?
Amputation in the event of a non-viable limb:
- tissue loss (gangrene)
- nerve damage
- sensory loss
- skin mottling
- plantar fasciitis
What is the management plan for acute limb ischaemia?
- IV heparin initially (unless CI)
- urgent assessment for revascularisation + thrombolysis (urokinase or alteplase) OR amputation (if non-viable limb)
- antiplatelet therapy (aspirin/clopidogrel)
- analgesia (paracetamol+opioid) + fluids + O2
What surgical options are available for acute limb ischaemia? (3)
- endovascular revascularisation + intra-arterial thrombolysis (urokinase or alteplase)
- bypass (surgical revascularisation) - if stenosis>10cm or chronic occlusion>5cm
- amputation
What is the sole treatment for acute limb ischaemia with a viable limb / whilst awaiting transfer to vascular specialists?
IV heparin
What are some complications of PAD? (3)
- arterial ulcers
- gangrene
- permanent limb weakness/numbness/pain
Describe the prognosis of claudication symptoms (PAD).
Remain stable and has good prognosis
Describe the prognosis of critical limb ischaemia (PAD).
Poor prognosis
