Peripheral vascular disease Flashcards
How common is it?
20% of people over 60 years have some degree of peripheral arterial disease.
Acute limb ischaemia has an incidence of around 1 in 12,000 people per year. Chronic limb ischaemia is much more common than this
Who does it affect?
The prevalence is greater in people with cardiovascular disease and risk factors such as diabetes mellitus, smoking, and dyslipidaemia than in the general population.
What causes it?
Atherosclerosis which narrows the affected arteries. This limits blood flow to the muscles and other tissues. Critical limb ischaemia is usually caused by obstructive atherosclerotic arterial disease, but rarely it is due to vasculitis, thromboangiitis obliterans, cystic adventitial disease, popliteal entrapment or trauma.
What risk factors are there?
Smoking is the big one. Diabetes mellitus, hypertension and dyslipidaemia.
How does it present?
Acute limb ischaemia: When there is an onset of leg pain over minutes, hours, or days associated with: Pulseless, pallor, painful, paraesthesia, paralysis and perishingly cold.
Chronic limb ischaemia: Progressive development of cramp-like pain in the calf on walking, or unexplained foot pain at rest (worse at night). Non-healing wounds on the lower limb. Peripheral pulses are absent or may be difficult to feel.
Investigations
Blood pressure.
FBC (anaemia will aggravate PAD),
ESR (inflammatory process – e.g. giant cell arteritis)
ABPI
thrombophilia screen
Fasting blood glucose
Lipid levels
ECG: 60% of patients with intermittent claudication have ECG evidence of pre-existing coronary heart disease.
Patients <50 should also have a thrombophilia screen and serum homocysteine levels taken.
Treatment
Smoking cessation
regular exercise
weight reduction
ACE inhibitors
Statins
Manage diabetes
Antiplatelet drugs
Peripheral vasodilators e.g. Naftidrofuryl oxalate
Angioplasty or bypass surgery, but it is inconclusive if this is better than lifestyle changes.
Conditions that would present similarly
The differential diagnosis of pain in the lower limb when walking includes sciatica and spinal stenosis, DVT, entrapment syndromes and muscle/tendon injury. Diabetic neuropathy.
