Flashcards in Peripheral Vascular Disease Deck (36)
How many 65-75 year olds have PVD on examination?
1 in 5.
How many 65-75 year olds with PVD on examination have symptoms?
What is an atheroma?
Accumulation of intracellular and extracellular lipid in the intima and media of large and medium sized arteries.
What is atherosclerosis?
Thickening and hardening of arterial walls as a consequence of atheroma.
What are fatty streaks in atheromas?
Lipid deposits in intima, yellow and raised.
What are the features of a simple plaque atheroma?
Raised yellow/white, irregular outline, widely distributed, enlarge and coalesce.
What are the features of a complicated plaque atheroma?
Thrombosis, haemorrhage into plaque, calcification, aneurysm formation.
Where are the common sites of atheromas?
Aorta, coronary arteries, carotid arteries, cerebral arteries, leg arteries.
What are the early microscopic changes of atheromas?
Proliferation of SMC, accumulation of foam cells, extracellular lipid.
What are the late microscopic changes of atheromas?
Fibrosis, necrosis, cholesterol clefts, ± inflammatory cells, disrupted internal elastic lamina, media damaged, blood vessel ingrowth, plaque fissuring.
What is intermittent claudication?
Pain in the muscles of the lower limb elicited by walking/exercise.
Which muscles are mostly affected by intermittent claudication?
Calf muscles - gastrocnemius, soleus, triceps surae.
What is the timing of pain of intermittent claudication?
Pain on walking but rapidly relieved by stopping for a few minutes.
What causes pain in intermittent claudication?
Muscle oxygen demand and supply -> muscle ischaemia -> anaerobic metabolism -> lactate/K+, substance P -> pain.
What are the differential diagnoses for intermittent claudication?
Spinal stenosis, lower limb arthritis, musculoligamentous strain.
What are the three most common sites of atheromas causing intermittent claudication?
Superficial femoral artery (80%), aorto-iliac arteries (15%), calf arteries (5%).
What are the normal symptomatic presentations of intermittent claudication?
Calf claudication (80%).
Calf, thigh and buttock claudication (18%).
Bilateral buttock claudication + erectile failure = Leriche's syndrome (2%).
What are the risk factors for PVD?
Smoking, hypercholesterolaemia/hyperlipidaemia, hypertension, diabetes mellitus, family history, ischaemic heart disease, cerebrovascular disease.
What is the natural history of intermittent claudication?
80% will have no progression over 5 year.
After 5 year - 11% who continue to smoke will have an amputation, 0% in those who stop smoking.
Amputation rate over 5 years in diabetics is 4 x normal.
Which questions need to be asked in a history of intermittent claudication?
When do they have cramp? When did it start? Is it relieved by rest? How far before pain? Interference with lift? Risk factors? Past medical history?
What would be seen on examination of the leg in intermittent claudication?
Inspection - pale colour, poor skin condition, loss of hair.
Palpation - cold temperature, slow capillary refill, weak peripheral pulses, aneurysms.
Auscultation - bruits, heart and carotid auscultation.
What are the investigations to be done for intermittent claudication?
FBC, blood glucose, serum lipids. ABPI, treadmill testing.
What is ABPI?
Ankle brachial pressure index = ankle systolic pressure/brachial systolic pressure.
What is the treatment of intermittent claudication?
Stop smoking, correct risk factors, exercise, percutaneous transluminal angiopalsty, surgical bypass, pharmacological.
Why is smoking cessation so important for management of intermittent claudication?
Biggest PAD risk factor, atherogenic, lowers HDL, raises lipids, raises platelet adhesion, raises fibrinogen levels. Stopping increases walking distance, decreases mortality.
Which antiplatelet drug should be given in intermittent claudication and why?
Clopidogrel - reduces 5 year risk of combined death/MI/CVA by 25%.
Why should statins be given in intermittent claudication?
Reduces 3 year risk of cardiac/CVA events by 25% and mortality by 12%.
Which patients with intermittent claudication should be given statins?
All of them - regardless of their starting cholesterol value.
What is the purpose of exercise rehabilitation in intermittent claudication?
Improves walking technique, optimises collateral blood distribution, improves capillary perfusion.