Peripheral Vascular Disease

Question 1

What is meant by peripheral arterial disease?

Answer 1

Progressive narrowing of the arteries supplying the limbs and periphery, reducing the blood supply to these areas.
Usually affects the lower limbs resulting in symptomatic manifestations such as claudication

Question 2

What is meant by intermittent claudication?

Answer 2

Symptoms of ischaemia in alimb
Occuring during exertion and relieved by rest
Crampy, achy pain in calf, thigh or buttock muscles associated with muscle fatigue (aka when walking), when oxygen/blood supply is insufficient to reach demand

Question 3

What is meant by critical limb ischemia?

Answer 3

End-stage, most severe form of peripheral arterial disease
Inadequate supply of blood to a limb at rest - unable to function at rest/low exertion - unable to meet metabolic demand
High risk of amputation
Presents with chronic rest pain, non-healing wounds or gangrene.

Question 4

What are the key signs and symptoms of critical limb ischemia?

Answer 4

Pain in limb at rest
Non-healing ulcers
Gangrene
Pain worse at night when leg is raised - gravity no longer helps pull blood into the foot, pain relieved by hanging foot off the end of the bed.

Question 5

What is acute limb ischemia?

Answer 5

Rapid onset ischemia of a limb
Norm caused by thrombus of a distal artery to a limb
Severe manifestation of PAD
Presents with the 6Ps, requires immediate restoration of blood to the affected limb through revascularization process.

Question 6

Define ischemia

Answer 6

Inadequate oxygen supply to tissues due to reduced blood supply

Question 7

Define gangrene

Answer 7

Death of tissue, specifically due to an inadequate blood supply.

Question 8

What is meant by athersclerosis?

Answer 8

Atheroma formation (fatty deposits in artery walls) and sclerosis (harding or stiffening of the blood vessel walls)
Mainly affects the medium and large arteries.
Caused by chronic inflammation and activation of the immune system in the artery wall.
Lipids deposited in artery walls

Question 9

What are the consequences of atheromatous plaque formation in arteries?

Answer 9

Mainly affects large and medium blood vessels
Stiffening of wall = hypertension and increased strain on heart as pump against more resistance
Stenosis - reduced blood flow aka angina
Plaque rupture - resulting in a thrombus causing ischemia

Question 10

What are some risk factors for atherosclerosis?

Answer 10

Increased age (particularly over 50y)
Family history -(hypercholesterolemia /dyslipidaemia)
Smoking - poor vascular health
HTN - endothelial dysfunction
Diabetes Mellitus - chronic hyperglycemia leads to endothelial dysfunction inc atherosclerosis formation

Alcohol consumption
Male
Poor diet (high in sugar/trans fat, low in fruit, veg and omega 3s)
Low exercise/sedentary lifestyle
Obesity
Poor sleep
Stress

Question 11

What medical co-morbidities tend to be associated with atherosclerosis?

Answer 11

Diabetes
Hypertension
Chronic Kideny Disease
Inflammatory conditions such as rheumatoid arthiritis
Atypical antipsychotic medications

Question 12

What are some of the clinical ways that atherosclerosis can present?

Answer 12

Angina
Myocardial infarction
Transient Ischaemic attack
Stroke
Peripheral Arterial Disease
Chronic Mesenteric ischaemia

Question 13

What is the key symptom of peripheral arterial disease?

Answer 13

Intermittent claudication
Crampy pain typically in calf (thigh or buttock) that occurs predictably when walking a certain distance then resolves on rest.

Question 14

What are the key features of acute limb ischemia?

Answer 14

Pain
Pallor
Pulseless
Paralysis
Paraesthesia (pin and needles)
Perishinling cold

Question 15

What is leriche syndrome?

Answer 15

Occlusion in the distal aorta or proximal common iliac artery
Presents with the clinical triad of:
Thigh/buttock claduciation
Absent femoral pulses
Male impotence

Question 16

What signs on examination can indicate a peripheral vascular disease?

Answer 16

Tar staining on fingers
Xanthomata (yellow cholesterol deposits on the skin)
Signs of cardiovascular disease - amputation, midline sternotomy scar/ scan on inner calf (prev CABG), focal weakness from stroke
Weak pulses of (may assess further using a hand-held doppler)
Skin pallor
Cyanosis
Dependent rubor
Muscle wasting (atrophy)
Hair loss
Ulcers
Poor healing wound
Gangrene
Cold skin
Reduced sensation
Prolonged cap refill
Changes during burgers test.

Question 17

How do you perform Buergers test?

Answer 17

Patient supine
Lift lefs to 45 degrees hip flexion
Hold for 1-2mins = looking for pallor
Pallor indicates artery not able to overcome gravity = PAD
Gradually lower the legs to identify angle when legs become pale = burgers angle
Sit patient over side of bed, legs handing down - blood flow now associated by gravity
health - normal pink
PAD - blue as ischemia tissue deoxygenated the blood, then dark red (rubor) due to vasodialtion in response to waste products of anerobic resporation

Question 18

What is the main cause of arterial ulcers?

Answer 18

Damage caused by ischemia secondary to inadequate blood supply.
Skin/tissue struggles to heal due to impaired blood flow

Question 19

What are the key features of arterial ulcers?

Answer 19

Tend to be smaller than venous ulcers
Deeper than venous ulcers
Well defined borders
Punched-out appearance
Occur peripherally aka on the toes
Reduced bleeding
Are painful

Question 20

What is the main cause of venous ulcers?

Answer 20

Impaired drainage and pooling of blood in the legs

Question 21

What are the key features of venous ulcers?

Answer 21

Occur after a minor injury to the leg
Larger than arterial ulcers
More superficial than arterial ulcers
Have irregular, gently sloping borders
Affect the gaiter area of the leg (mid-calf down to the ankle)
Are less painful than arterial ulcers
Occur with other signs of chronic venous insufficient e.g haemosiderin staining and venous eczema

Question 22

What investigations should be done for someone with suspected peripheral arterial disease?

Answer 22

ABPI - ratio systolic BP in ankle to arm, 0.9-1.3 is norm, high indicated calcification low indicates PAD
Duplex ultrasound - speed and vol of blood flow
Angiography (CT or MRI) - contrast the highlight arterial occlusion

Question 23

What lifestyle changes and non-medical treatment is recommended to treat intermittent claudication?

Answer 23

Manage modifiable risk factors - e.g stop smoking, maintain a healthy weight
Well managed co-morbidities - HTN and DM
Exercises - structured and supervised regular walking to the point of near maximal claudication and pain, then resting and repeating

Question 24

What medical treatments are given for intermittent claudication?

Answer 24

Atorvastatin 80mg
Clopidogrel 75mg daily
Naftidrofuryl oxalate (5-HT receptor antagonist = peripheral vasodilator) when exercise made no improvement and not suitable for angioplasty/bypass - review every 3-6 months.

Question 25

What are the surgical options for the treatment of intermittent claudication?

Answer 25

Endovascular angioplastly and stenting Endarterectomy - cutting vessel open and removing the athermoatous plaque Bypass surgery - using a graft to bypass the blockage.

Question 26

What is the typical management of critical limb ischaemia?

Answer 26

Assessed by a vascular MDT before treatment decisions are made. Endovascular angioplasty and stenting Bypass surgery Endarterectomy Amputation of the limb if not possible to restore the blood supply. Analgesia to manage the pain

Question 27

What are the management options for acute limb ischaemia?

Answer 27

Endovascular thrombolysis - inserting a catheter through the arterial system to apply thrombolysis directly into the clot Endovascular thrombectomy - catheter through the arterial system to remove thrombus by aspiration or mechanical devices Endarterectomy Bypass surgery Amputation of the limp if it is not possible to restore the blood supply.

Question 28

What are some potential underlying causes of PAD?

Answer 28

Atherosclerosis - primary cause, leads to stenosis and reduced blood flow, gradual Arterial inflammation - contribute to atherosclerosis, vasculitis or SLE Thromboembolism - acute arterial occlusion, uncommon but severe inc;using intermittent claudication

Question 29

Describe the basic process by which atheromatous plaques form?

Answer 29

Endothelial dysfunction - damage to endothelium prompts an inflammatory response, leading to increased vascular permeability and allowing lipids to infiltrate the intima. Lipid accumulation - LDL oxidised within intima, triggers phagocytosis by macrophages, foam cell formation Fibrous cap formation - smooth muscle cells migrate from the media to the intima, proliferate and produce ECM matrix proteins contributing to fibrous cap formation

Question 30

What imaging should be ordered before revascularisation for PAD patient?

Answer 30

Offer duplex ultrasound as a first line imaging to all. Offer contrast enhanced magnetic resonance angiography to people with PAD requiring further imaging Offer CT angiography if above contraindicated or not tolerated.

Question 31

What type of exercise programme is recommended for people with intermittent claudication?

Answer 31

Supervised exercise programe Encourage to reach point of maximal pain 2hrs supervised exercise a week for a 3 month period.

Question 32

When should surgical intervention be offered for patients with intermittent claudication?

Answer 32

When advice on the benefits of modifying risk factors has been reinforced Supervised exercise programme has not led to a satisfactory improvement in symptoms Imaging has confirmed that angioplasty is suitable for a person. Typically only for complete aorta-iliac occlusion (not stenosis), and not for femoro-popliteal disease. Should use bare metal stents

Question 33

How is the pain managed in critical limb ischemia?

Answer 33

Paracetamol, weak/strong opioids depending on the severity of pain. May need laxatives and anti-emetics to manage adverse effects of strong opioids Should be referred by pain management team is pain continues after revascularisation/amputation or prolonged strong doses of opioids.

Question 34

When should major amputation be considered in people with critical limb ischemia?

Answer 34

All options for revascularisation must have already been considered by a vascular MDT.

Question 35

What differential diagnosis need to be considered in patients with peripheral arterial disease?

Answer 35

Lumbar spinal stenosis Deep vein thrombosis Chronic venous insufficiency

Question 36

What is lumbar spinal stenosis? Relevant as a differential to PAD

Answer 36

Pain in the lower extremities, worse on activity Neurogenic claudication - weakness or numbness, neurogenic pain often along dermatomal pattern Relief on bending forward or sitting down, typically takes 30-40 mins. Pain presents on variable distances - good v bad days.

Question 37

What is DVT as a differential to PAD?

Answer 37

Leg pain and discomfort Also unilateral swelling, warmth and erythema - not seen in PAD More acute in onset and persistent rather than episodic as in PAD

Question 38

What is chronic venous insufficiency as a differential to PAD?

Answer 38

Aching discmofort in the legs Persistent oedema and skin changes - pigmentation or ulceration Improves with leg elevation or ambulation (contrasting to intermittent claudication)

Question 39

What are some complications of PAD presenting as intermittent caludication?

Answer 39

Critical limb ischemia - chronic rest pain, non-healing ulcers or gangrene Acute limb ischemia - thromboembolism or plaque rupture, 6Ps Infection - reduced blood flow inc susceptibility to infection such as cellulitis and osteomyelitis, particularly in ulcers or gangrene Tissue necorsis - persistent hypoperfusion, auto-amputation or surgical removal Cardiovascular events - MI, stroke due to shared athersclerotic pathology. Functional impairment and disability - chronic pain and reduced mobility.

Question 40

What are the 6Ps of acute limb-threatening ischemia?

Answer 40

Pain Pallor Pulselessness Paralysis Paraesthesia Perishingly cold

Question 41

What are some common underlying causes of acute lime-threatening ischaemia in PAD?

Answer 41

Atherosclerosis - narrowed wall - reduced reserve Arterial embolism - sudden occlusion and resultant ischaemia Buergers disease - rare, thromboangiitis obliterans, inflammation and clots in blood vessels of hands and feet, progressive stocking pattern Raynauds disease - exacerbate PAD, small arteries supplying the skin narrow.

Question 42

What is reperfusion injury?

Answer 42

When blood flow is restored, either spontaneously or therapeutically. Release of ROS and inflammatory mediators from ischemic tissue upon reoxygenation Results in endothelial dysfunction and microvascular permeability - further tissue damage.

Question 43

What are the main different types of vascular disease?

Answer 43

Arterial - tends to be occlusive or aneurysmal Venous - tends to be varicose or incompetent

Question 44

In what time frame should you aim to revascularize an occlusion of blood flow to the lower limb in acute life-threatening limb ischemia (PAD)?

Answer 44

6hrs.

Question 45

Describe how ABPI is calculated and should be interpreted to show PAD.

Answer 45

Systolic BP in ankle /arm Greater than 1.3 indicates arterial calcification 1 = normal 0.8 to 10.3 - no severe PAD, possibly occurring in early disease process. 0.5 to 0.8 - presence of PAD Less than 0.5 - suggests severe arterial disease

Question 46

What blood pressure in the ankle indicates critical limb ischemia?

Answer 46

<60 mmHg in non-diabetic patients

Question 47

What are some rarer causes of critical limb ischemia?

Answer 47

Buergers disease Popliteal aneurysm Popliteal entrapment Cystic adventitial disease Trauma Aortic dissection