Peripheral Vascular Disease (PVD)

Question 1

Define Peripheral Vascular Disease (PVD)

Answer 1

Obstruction of large arteries not within the coronary, aortic or brain vasculature.

Question 2

What are the causes of PVD?

Answer 2

• Atherosclerosis
• Inflammation leading to stenosis
• Thrombosis
• Emboli

Question 3

What are the risk factors for PVD?

Answer 3

• Sex: male
• Age : older
• Diabetes mellitus
• BP high
• Elevated cholesterol (hyperlipidaemia)
• Tobacco
• Renal disease
• Obesity
• Homocysteinaemia

Question 4

What are the stages of Atherosclerosis?

Answer 4

1. Fatty Streak
2. Fibrous Plaque
3. Atherosclerotic Plaque
4. Plaque rupture/ fissure & thrombosis

Question 5

What symptoms may an atherosclerotic plaque produce?

Answer 5

• Stable angina
• Intermittent claudication

Question 6

What symptoms may a ruptured plaque/ fissure & thrombosis produce?

Answer 6

• Unstable angina
• MI Stroke/ TIA
• Critical leg ischaemia
• Cardiovascular death

Question 7

What are symptoms of PVD?

Answer 7

• Intermittent claudication
• Rest pain (burning distally)
• Blueness or paleness
• Coolness
• Gangrene
• Sores, wounds or ulcers (slowly or not healing)
• Infection (between toes)
• Diminished hair & nail growth where affected

Question 8

What is Leriche’s syndrome? What does it indicate?

Answer 8

1. Buttock intermittent claudication
2. Sexual impotence
3. Absent femoral pulse

• Indicates bilateral aorto-iliac occlusion

Question 9

Define gangrene

Answer 9

Tissue necrosis with putrefaction

Question 10

Describe dry gangrene

Answer 10

• Necrosed tissue mummified following infarction
• Black (haemoglobin breakdown) and dry
• Cellulitis spreads
• Zone of demarcation

Question 11

Describe wet gangrene

Answer 11

• Superadded infection with the spore- and gas- forming anaerobe Clostridium perfringens
• Severe pain, patient septic & unwell
• Gas collection in subcutaneous tissue results in crepitus
• Cellulitis does not spread
• No zone of demarcation

Question 12

What examinations would you perfume on suspected PVD?

Answer 12

• Pulses in limbs (& evidence of AF)
• BP
• Temperature of both limbs
• Palpate for abdo, femoral & popliteal aneurysm
• Capillary refill of toes
• Ankle-brachial pressure index (ABPI)
• Doppler

Question 13

What is Buerger’s angle/ sign?

Answer 13

The angle at which the foot becomes white when raised from lying flat

A normal leg should remain perfused at 90 degrees

Question 14

What is an ABPI and what does it show?

Answer 14

Ankle-brachial pressure index

The difference between brachial and ankle

• BP 0.9-1.2 = normal
• 0.4-0.8 = moderate arterial disease, consistent with claudication
• <0.4 = severe ischaemia, consistent with rest pain

Question 15

What investigations would you perfume in suspected PVD?

Answer 15

• Arterial ultrasound scan with duplex
• Angiography
• CT
• Magnetic resonance angiography

Question 16

Describe arterial ultrasound scan with duplex

Answer 16

• Determines degree of blood flow (& extent of atherosclerosis)
• Waveform
  
  • Triphasic = normal
  • Biphasic = moderate disease
  • Monophasic = significant disease

Question 17

Describe angiography

Answer 17

• Goild standard anatomical definition of the arterial tree
• Intra-arterial contrast, CT or magnetic resonance
• Done when surgery of angioplasty/ stent considered

Question 18

What are the risks of angiography?

Answer 18

• Bleeding
• False aneurysm
• Thrombosis
• Distal embolization
• Allergic reaction to contrast
• Nephrotoxicity

Question 19

Describe Fontaine’s classification of PVD

Answer 19

1. Stage 1 = Asymptomatic
2. Stage 2 = Intermittent claudication
3. Stage 3 = Rest pain
4. Stage 4 = Ulceration and/or grangrene

Question 20

Define critical limb ischaemia

Answer 20

Chronic or acute-on-chronic ischaemia that endangers the whole or part of a leg

Question 21

What are signs of critical limb ischaemia?

Answer 21

• Rest pain
• Tissue loss
• Ankle pressure <50mmHg
• Toe pressure less than 30mmHg

Question 22

What are indications for intervention in lower limb ischaemia?

Answer 22

• Critical limb ischaemia
• Disabling claudication

Question 23

Detail risk factor modifications you would want to consider

Answer 23

• Smoking cessation
• Antiplatelet therapy
• Treatment of hyperlipidaemia
• Exercise programmes
• Diabetes management
• Hypertension management

Question 24

Describe the effectiveness of smoking cessation

Answer 24

• Improvement in claudication in 3-6 months
• Reduced risk of critical ishaemia, MI and mortality

Question 25

What are the aims of treating hyperlipidaemia?

Answer 25

LDL \<5.0mmol/l

Question 26

Describe the methods and indications for use of different antiplatelet therapys

Answer 26

* Aspirin * Lowers MI, stroke and death risk * Low dose as effective as high dose * Clopidogrel * Better than aspirin in lowering risks * Costly, use for; * Aspirin intolerance * Ineffectiveness of aspirin * High risk cases

Question 27

Outline the TASC guidelines

Answer 27

* Type A - endovasc. treatment * Single stenosis \<10cm * Single occlusion \<5cm * Type B - endovasc. treatment * Single \<15 * Multiple, each \<5 * Heavily calcified \<5 * Popliteal stenosis * Type C - surgery * Recurrent after 2 endovasc. interventions * Mulitple totalling \>15 * Type D - surgery * Chronic \>20 * Popliteal & prox. trifurcation vessels

Question 28

What is the treatment for patients with stable claudication?

Answer 28

* Risk factor reduction * Supervised exercise program * +/- Cilostazol - phosphodiesterase 3 inhibitor 1. Antagonise platelet aggregation 2. Increase heart contractility 3. Enhance vascular smooth muscle relaxation

Question 29

What surgical options are available in the treatment of PVD?

Answer 29

* Angioplasty * Plaque excision * Bypass grafting

Question 30

Describe angioplasty

Answer 30

* Mechanically widen narrowed/ obstructed arteries using water-inflated balloon * Poor sustained benefits

Question 31

Describe bypass grafting

Answer 31

* Needed to circumvent seriously stenosed areas * Saphenous vein \> short SV \> aim veins OR synthetic (ePTFE) graft * Synthetics & veins equal in larger arteries * Synthetics perform poorly in smaller arteries

Question 32

What is Buerger's disease (thromboangiitis obliterans)? Outline; * Aetiology * Presentation * Diagnostic criteria

Answer 32

Chronic segmental inflammation & thrombosis of small-medium sized arteries & veins of peipheral upper & lower limbs (especially hands & feet). Aetiology * Young men * Smoking * Lower socio-economic groups Presentation (mainly hands & feet) * Claudication to severe rest pain * Exactly the same but more **aggressive** than PVD * Reynaud's phenomenom * Later: enlarged, red, tender cord-like veins Diagnostic criteria * Shionoya * Smoking history * Onset \<50yrs * Infrapopliteal arterial occlusions * Either arm involvement or phebitis migrans * Absence of atherosclerotic risk factors other than smoking

Question 33

What is Subclavian Steal Syndrome? * Definition * Causes * Presentation

Answer 33

Definition * **Subclavian steal phenomenon**: Stenosis/ occlusion of subclavian artery proximal to vertebral artery origin ⇒ ipsilateral backflow in that vertebral artery * **Subclavian steal syndrome**: Symptoms in upper limb, brain or heart. Causes * Artherosclerosis * Surgical repair of coarctation or Fallot's tetralogy * Asia 36% due to Takayasu's arteritis (early presentation, females) Presentation (2% symptomatic) * Arm claudication, pain, fatigue * On exercising the upper limb ⇒ Cerebellar signs * Vertigo * Visual loss * Ataxia, diplopia, dysphagia, dysarthria * Tingling/ numbness of the face * Sensory hemianaesthesia/ transient hemiparesis * Syncope * Signs * BP decreased in affected arm (/ difference of 10mmHg) * Collapsing pulse

Question 34

What is Takayasu's arterisis?