Chronic Peripheral Arterial Occlusive Disease Flashcards
What is peripheral arterial disease?
Narrowing of peripheral arteries, namely non-cardiac/cerebral
What are the common causes of PAD?
Atherosclerosis causing stenosis of arteries
Fibromuscular dysplasia
Buerger’s disease
How can PAD be classified?
Fontaine classification
- asymptomatic
- intermittent claudication
- ischaemic rest pain
- ulceration/gangrene (critical ischaemia)
What ABPI values correspond to PAD?
<0.8 - Arterial disease present
<0.4 - Critical limb ischaemia
>1.2 - False negative, abnormally stiff vessels (DM)
What are the symptoms of intermittent claudication?
Cramping pain on exercise, relieved by rest
Exercise limit consistent (claudication distance)
Calf - Femoral OR Thigh/Buttock - Ileal
What is Leriche syndrome?
Triad of:
- Buttock/thigh pain
- Absent femoral pulses
- Erectile dysfunction
What are the signs of intermittent claudication?
Absent pulses Cold, pale legs Atrophic, hairless, shiny skin Beurger's angle <20o Arterial ulcers
What does ischaemic rest pain suggest?
Critical lower limb ischaemia
How does ischaemic rest pain present?
At night, in forefoot
Wakes pt from sleep
Relieved by swinging leg over side of bed/walking on cold floor
What investigations are appropriate in PAD?
FBC, HbA1c, lipids
ABPI
MR/CT angio
How should PAD be managed if ABPI >0.6?
Progression unlikely so conservative Lifestyle changes Raising heel of shoes Foot care Optimise BP/DM Clopidogrel & Atorvostatin
What clinical signs can distinguish intermittent claudication from other causes of leg pain?
Pale Pulseless Perishingly Cold Painful Paresthetic Paralysis Loss of hair
How should PAD be managed if ABPI <0.6?
Percutaneous Transluminal Angioplasty (PTA)
Surgical reconstruction
Sympathectomy (if surgery impossible, relieves sx)
Amputation
What are the three main effects of peripheral neuropathy on the presentation of PAD?
Sensory - Reduces reaction to minor injury/awareness of sx
Autonomic - No sweat, develop dry/fissured skin
Motor - Wasting of small muscles of foot, develop abnormal pressure areas
How does peripheral neuropathy alone present?
Stabbing pains in feet that are red, warm and have strong pulses
How does peripheral neuropathy + PAD present?
Severely ischaemic yet painless
Ulceration –> Gangrene
What is gangrene?
Dead tissue colonized by bacteria
What are the two main types of gangrene?
Wet - Infected w/ proliferating organisms
Dry - Colonized, no proliferation
How does gangrene present?
Distal at first, progress proximally to healthy tissue
Blue-purple at first, becomes black
Presents early/in smaller areas in DM
If purely arterial affects larger areas
What is the pathophysiology underlying intermittent claudication?
Atheromatous femoral artery
At rest O2 req of muscles met by collateral system of profunda femoris
Exercise increases demand, calf muscles ischaemic
What is the DDx for intermittent leg pain?
Spinal stenosis Venous claudication Musculoskeletal Peripheral neuropathy Popliteal artery entrapment
How can spinal stenosis be distinguished from intermittent claudication?
Pain relieved by sitting down/flexing spine
Sx variable day-day
Pulses present
Confirmed on MRI
How can venous claudication be distinguished from intermittent claudication?
Pain comes on gradually from start of walking
Affects whole leg, described as ‘bursting’
Leg elevation relieves pain
Signs of venous disease/history of DVT
What are the most common types of ulcers?
Venous (85%)
Arterial (10%)
Diabetic/Neuropathic
What is the pathology underlying a venous ulcer?
Venous HTN/oedema causes sc hypoxia
Minor trauma causes ulcer
2o infections by skin flora common
What are the clinical features of venous ulcers?
Hx - DVT, varicosities, obesity Pain - Rare Site - Gaiter area, medial malleolus Progression - Slow, can become v. large Oedema - Common Skin - Red, warm, signs of venous insufficiency Ulcer - Shallow, flat margin
What is the pathology underlying an arterial ulcer?
Commonly occur after an episode of minor trauma w/ inadequate healing due to PAD
What are the clinical features of arterial ulcers?
Hx - IC, IHD, HTN, DM Pain - V. painful Site - Lat malleolus, toes/heel Progression - Rapid, present small Oedema - Uncommon Skin - Shiny, hairless, atrophic nails, cold, pale Ulcer - Small, punched out
How do diabetic ulcers present?
Unbalanced looking foot w/ ulcers on pressure areas
Painless due to neuropathy
How are ulcers managed conservatively?
Lifestyle changes
Avoid prolonged standing (venous)
Control DM
How are ulcers managed if APBI >0.8 & signs of venous disease?
4 layer compression bandaging
Leg elevation
Long term compression stockings
How are ulcers managed if APBI <0.8?
Refer to GP for CV risk modification
Refer to vascular surgery
May require compression if venous component
How should superficial venous disease be managed?
Treatment of varicose vv may resolve outflow issues, allowing ulcer healing
How does chronic small bowel ischaemia present?
Severe post-prandial colic (gut claudication)
PR bleeding
Wt loss
Malabsorption
How should chronic small bowel ischaemia be investigated?
Visualised on angiography
How is chronic small bowel ischaemia managed?
Angioplasty
How does large bowel ischaemia present?
ISCHAEMIC COLITIS
L. sided abdo pain
Bloody diarrhoea
Pyrexia, tachycardia, leukocytosis
What is the major complication of large bowel ischaemia?
Progression to gangrenous colitis
Pt peritonitic and shocked
How should large bowel ischaemia be investigated?
Barium enema/AXR (thumb printing)
MR angiography
How is large bowel ischaemia managed?
Conservative - Fluids & a/b
PTA & stenting if severe
What are the causes of renal artery stenosis?
Atherosclerosis (80%) Fibromuscular dysplasia (10%, young males)
How does renal artery stenosis present?
Resistant HTN
Worsening renal func after ACEIs (if bilateral)
Sudden onset pulmonary oedema (normal LV func)
Renal bruits
How should renal artery stenosis be investigated?
Renal USS - Small, disturbed flow
CT/MR angio
Renal angio gold standard
How is renal artery stenosis managed?
Medical - ACEIs w/ statins & antiplatelets (not if bilateral)
Surgical - Angioplasty and stenting
What are the surgically/radiologically curable causes of HTN?
Conn’s
Phaeochromocytoma
Polycystic Kidneys
Coarctation of Aorta
