Peripheral vascular disease

Question 1

Define Peripheral Vascular Disease

Answer 1

range of arterial/vascular syndromes causes by atherosclerotic obstruction of the lower-extremity vessels

Question 2

Aetiology of Peripheral vascular disease

Answer 2

Atherosclerosis → insufficient tissue perfusion

Aortic coarctation, arterial fibrodysplasia, arterial tumours, arterial dissection
Embolism, thrombosis, vasospasm
Trauma
Thoracic outlet obstruction
Vasculitis: Takayusu’s arteritis, temporal arteritis, Buerger’s disease

Question 3

What are the 3 stages of venous gangrene

Answer 3

Phlegmasia alba dolens (white leg)
Phlegmasia cerulea dolens (blue/red leg)
Gangrene (secondary to acute ischaemia)

Question 4

Risk factors for Peripheral vascular disease

Answer 4

Smoking
Diabetes
Hypertension
Hyperlipidaemia
Age >40
Sedentary lifestyle

Question 5

What are the stages of Peripheral vascular disease

Answer 5

Fontaine stages
I Asymptomatic
IIa Mild claudication
IIb Moderate to severe claudication
III Ischaemia rest pain
IV Ulceration or gangrene

Question 6

Symptoms of Peripheral vascular disease

Answer 6

Asymptomatic (50%)

Intermittent claudication (pain, cramps, parasthesia distal do occlusion)
thigh or buttock pain with walking, relieved by rest
Sudden onset severe leg pain + numbness, weakness, pale and cold leg
Erectile dysfunction
Non-healing wound/ulcer

Question 7

What are the symptoms of critical limb ischaemia

Answer 7

Resting pain
Ulcer
Tissue loss (gangrene)
Night pain - burning pain relieved by hanging legs over the side of the bed

Question 8

Signs of Peripheral vascular disease

Answer 8

Diminished or absent pulses
Muscle atrophy
pallor on leg elevation
Loss of hair over the dorm of the foot
Thickened toenails
Shiny/scaly skin
gangrene, ulcers, necrosis
Pale extremities

Question 9

6 P’s of Peripheral vascular disease

Answer 9

Pale
Pulseless
Painful
Paralysed
Paraesthesia
Perishingly cold

Question 10

Investigations for Peripheral vascular disease

Answer 10

Ankle-brachial index (ABI): <0.9 = PAD
Toe brachial index: <0.6

CK: check for muscle damage

Duplex USS: peak systolic velocity ratio >2 (stenosis)
Continuous wave Doppler USS: Pulsatility index decrease

Catheter angiography, CT angiogram, MR angiography: anatomical detail of stenoses or occlusion

Question 11

What is Leriche syndrome

Answer 11

peripheral vascular disease at the level of aortic bifurcation.
Triad of:
Bilateral buttock, hip or thigh claudication
Erectile dysfunction
Absent/diminished femoral pulses

Question 12

How is the ankle brachial index (ABI) used

Answer 12

Ratio of systolic ankle BP to systolic brachial BP
Normally, ankle BP and brachial BP are equal (ABI = 1), or ankle BP is only slightly higher because of gravity (ABI > 1)

• > 1.3 = medial sclerosis with incompressible vascular wall (generally calcified vessels)
• 1.0–1.30 = normal value
• 0.91–0.99 = borderline
• 0.40– 0.90 = mild to moderate PAD → claudication
• < 0.40 = severe PAD → resting pain, gangrene (critical limb ischemia)

However, diabetic patients have artificially high ABPI values as their arteries are not easily compressible due to calcification.

Question 13

Management for chronic peripheral artery disease

Answer 13

Conservative: compression bandages (ABPI >0.8), exercise, risk factor modification
Medical:
- Antiplatelet: aspirin 75mg PO OD + PPI
- Symptom relief: cilostazol or naftidrofuryl

endovascular revascularization
- percutaenous transluminal angioplasty +/- stent placement
- endovascular techniques are typically used for short segment stenosis (e.g. < 10 cm), aortic iliac disease and high-risk patients

surgical revascularization
surgical bypass with an autologous vein or prosthetic material
endarterectomy
open surgical techniques are typically used for long segment lesions (> 10 cm), multifocal lesions, lesions of the common femoral artery and purely infrapopliteal disease

Surgical (grafts):
Natural:
- Trahere transplantation (transplant axillary vein and valve into deep venous system)
- Kistner operation (venous valvuloplasty)
- Palma operation (bypass venous operation with contralateral great saphenous vein)

Artificial:
- Above IL → Dacron graft (synthetic polyester graft)
- Below IL → PTFE (poly-tetra-flour-ethylene) graft

Question 14

management for acute limb ischaemia

Answer 14

IV heparin → revascularisation within 2-6h

Question 15

Management for critical limb ischaemia

Answer 15

Conservative: smoking cessation, treat comorbidities

Medical:
- 80mg atorvastatin
- 75mg clopidogrel
- unfractionated heparin
- Localised intra-arterial infusion of thrombolytics (urokinase/alteplase) ± mechanical thrombectomy device

Surgical:
- Percutaneous translumina balloon endovascular angioplasty (PTA)
- Stenting
- Bypass surgery

Amputation

Question 16

Complications of peripheral artery disease

Answer 16

Leg/foot ulcers
Gangrene
Permanent limb weakness/numbness
Permanent limb pain

Question 17

Prognosis for peripheral artery disease

Answer 17

PAD is related to morbidity and mortality from other types of atherosclerotic disease
Ankle brachial index (ABI) is a marker for cardiovascular events beyond the diagnosis of PAD
At 1 year, 25% of patients with critical limb ischaemia will have died and 30% will have undergone amputation