Chronic peripheral arterial disease Flashcards
How does chronic peripheral arterial disease usually present?
Intermittent claudication:
- Crampy pain on walking.
- Predictable.
- Relieved by rest.
- Limited to muscles.
- Classically worse on going up hill.
It is caused by there not being enough oxygen to meet the demand of the muscle, due to blockage from a atherosclerotic plaque.
What are the other differential causes for leg pain when walking?
Neurogenic claudication (due to lumbar spine stenosis):
- Not as bad going uphill or leaning forward.
- Classically worse going down hill
Venous claudication:
- Bursting pain worse on exercise.
- Swollen legs.
- Caused by flow reversal due to severe venous disease.
Cardiogenic claudication:
- Pain due to reduced cardiac output
What are the arterial trees which should be enquired about in a patient presenting with intermittent claudication?
- Cardiac
- Cerebrovascular
- Lower limb
- Mesenteric (mesenteric ischaemia*)
- Renal (aa stenosis)
*Presents with post prandial abdominal pain
What are the different stages of chronic peripheral aa disease?
- Asymptomatic
- Intermittent claudication
- Rest Pain
- Gangrene
Describe how to perform a vascular examination on a patient with peripheral aa disease?
Vascular examination:
- Inspection for colour, skin changes and ulcers (look at heel and between toes)
- Palpate for temperature
- Pulses (aorta to doralis pedis)
- ABPI
Describe how you would further investigate a patient with peripheral aa disease?
ABPI if it has not already been performed.
MR angiogram for disease:
- Below the knee (aka crural disease)
- Or above the groin (abdomino-iliac)
Duplex scan for disease:
- In between aka femoral popliteal disease
However would be reasonable to perform a duplex scan on all patients.
CT angiogram should be used in emergencies as others are not available or for patients in which MR is contraindicated:
- Metal work (including heart valves)
- Stents (MR doesn’t demonstrate blood flow well through stents)
- Claustraphobia
- eGFR less than 30 due to a rare reaction nephrogenic systemic fibrosis
Bloods: FBC (anaemia), HbA1c, lipids
Describe the consevative management of chronic peripheral vascular disease?
- Smoking cessation (most important)
- Simvastatin 40mg (lipid lowering + plaque stabilising)
- Clopidogrel 75mg
- Walking daily to limit of tolerability to encourage collateral formation
What is the surgical management of chronic peripheral vascular disease?
2 main approaches:
- Bypass graft: the blocked areais bypassed by creating a anastamosis with a grafted vein for example a femoral popliteal byapss will be used to treat an obstruction in the femoral aa.
- Angioplasty: widenning/removal of an atherosclerotic plaque usually with a stent insertion to keep it patent.
General rule is that angioplasty + stenting is more durable in larger vessesl therefore it is good in aorto-iliac disease and femoral-popliteal disease. Whereas it has poor durability in tibio-peroneal disease.
Describe the arterial supply of the leg?
Abdominal aa gives off the common iliac.
Common iliac becomes the internal and external iliac
The common femoral is the direct continuation of the external iliac (at the level of the inguinal ligament)
The common femoral aa gives off the profunda femoris and continues as the superficial femoral aa.
The superficial femoral aa becomes the popliteal aa.
The popliteal aa gives off the anterior tibial aa and the tibioperoneal trunk.
The anterior tibial aa passes through the interosseus membrane into the anterior compartment of the leg and gives the dorsalis pedis.
The tibioperoneal trunk divides into the posterior tibial and peroneal aa.
Describe ischaemic rest pain and differentiate it from neuropathic pain?
Ischaemic rest pain:
- Classically occurs in the feet
- When raised in bed.
- Improves on dangling the foot out of bed.
Neuropathic pain:
- Sharp shooting/burning pain
- Not be relieved by dangling the foot down.
- May be other neuropathic signs/symptoms (weakness/reduced sensation)
Describe the different types of gangrene and which is more common in diabetes?
Dry:
- Diminished blood supply (PAD) or vasculitic pictures
- Non infected
- Cold, dry and black
- May be initially painful but once tissue death occurs it will not be.
Wet:
- Caused by tissue infection
- Erythematous surrounding skin
- Discharge
- Painful
Diabetes is more associated with wet gangrene due to poor fit care due to peripheral neuropathy aswell as reduced immunity and wound healing. However diabetics are also at a increased risk of PAD.
Describe the features of an arterial ulcer?
- Punched out
- Necrotic
- Over pressure areas
- Painful
- Symptoms of arterial disease
Tend to occur distally or over pressure points, always check between toes and under the heal.
Describe the symptoms of a venous ulcer?
- Large
- Superficial
- Gaiter area
- Signs of chronic venous disease
- May or may not be painful
Tend to occur on the medial surface of the shin and on areas where there is bone close to the shin aka over tibia.
Describe the features of a neuropathic ulcer?
They usually occur in diabetics with peripeheral neuropathy and therefore usually occur on the foot. Can also have a venous or arterial cause also.
Venous ulcers are much more common and therefore are also much more common in diabetics.
Describe the clinical presentation of mesenteric occlusive disease/ angina
History:
- Moderate to severe colicky abdominal pain
- Poorly localised
- Post prandial
- Often weight loss due to fear of eating
Examination:
- Pain is often much worse than examination will suggest
- Initially may not be peritonitic
- Eventually will be peritonitic due to bowel necrosis and perforation.
Investigation:
- Lactate will be raised.
- May be a meabolic acidosis
- May be raised WCC
- AXR (normal)
- Gold standard is angiography
