peripheral vascular disease (A/C limb ischaemia)

Question 1

What is peripheral vascular disease?

Answer 1

Occurs due to atherosclerosis causing stenosis of arteries via a multifactorial process involving modifiable and non-modifiable risk factors

Question 2

What causes peripheral vascular disease?

Answer 2

Occurs due to ATHEROSCLEROSIS in peripheral arteries

Question 3

What are the different types of peripheral vascular disease?

Answer 3

1. Chronic limb ischaemia:
   a. Intermittent claudication - calf pain on exercise
   - Exercise increases muscle demand, which cannot be met by supply.
   - Improvement occurs by maintaining exercise to stimulate angiogenesis.
   b. Critical limb ischaemia - pain at rest:
   - NOTE: this is the MOST SEVERE manifestation of peripheral vascular disease
   - Can lead to tissue loss – gangrene/ulceration
   - Gangrene – death of tissue from poor vascular supply, sign of critical ischaemia
   - Arterial ulcers – abnormal breaks in an epithelial surface
2. Acute limb ischaemia:
   - a sudden decrease in arterial perfusion in a limb, due to thrombotic or embolic causes, or post angioplasty, trauma, iatrogenic – medical emergency requiring revascularisation within 4-6 hours to save limb
   - Two key causes: atherosclerotic plaque and atrial fibrillation

Question 4

What are the risk factors for peripheral vascular disease?

Answer 4

(same as the risk factors for any other atherosclerotic disease)
o Smoking
o Diabetes
o Hypertension
o Hyperlipidaemia
o Physical inactivity
o Obesity
o Family history
o Renal failure

Question 5

Summarise the epidemiology of peripheral vascular disease

Answer 5

● 55-70 yrs = 4-12% affected
● 70+ yrs = 15-20% affected
● More common in MALES
● Incidence increases with AGE

Question 6

What are the presenting symptoms of peripheral vascular disease?

Answer 6

1. Intermittent claudication - cramping pain in the calf, thigh or buttock after walking for a given distance (claudication distance) and relieved by rest
   o Calf claudication = femoral disease
   o Buttock claudication = iliac disease
2. Features of Critical Limb Ischaemia
   o Ulcers
   o Gangrene
   o Rest pain
   o Night pain (relieved by dangling leg over the edge of the bed)
3. Leriche Syndrome (aortoiliac occlusive disease)
   o Buttock claudication
   o Impotence
   o Absent/weak distal pulses

Question 7

What criteria is used to classify peripheral vascular disease?

Answer 7

1. Fontaine Classification of Peripheral Vascular Disease
   o Asymptomatic
   o Intermittent Claudication
   o Rest pain
   o Ulceration/gangrene
2. Rutherford Classification of acute limb ischaemia
   - Viable - no sensory deficit, audible doppler 
   - Marginally threatened - sensory loss, no audible doppler, tense calf 
   - Immediately threatened 
   - Non-viable - complete neurological deficit, mottling 

Question 8

What signs of peripheral vascular disease can be found on physical examination?

Answer 8

1. Acute Limb Ischaemia - 6 Ps
   o Pain
   o Pale
   o Pulseless
   o Paralysis
   o Paraesthesia
   o Perishingly Cold
2. Other symptoms:
   o Atrophic skin
   o Hairless
   o Punched-out ulcers (often painful)
   o Colour change when raising leg (to Buerger’s angle)
   o Brittle toenails

Question 9

What investigations are used to diagnose/ manage peripheral vascular disease?

Answer 9

1. ECG -check for AF 
2. ABPI (Ankle-Brachial Pressure Index) -FIRST LINE 
   - ABPI < 0.8 = do NOT apply a pressure bandage because this will worsen ischaemia 
   - The ratio of the systolic BP in the lower leg to that in the arms (brachial pressure). 
   - Lower blood pressure in the legs (result in a ABPI < 1) is an indicator of peripheral arterial disease (PAD) 
   - Higher ABPI may indicate calcified, stiff arteries causing FALSE NEGATIVES - seen in diabetes, RA 
3. CT Angiogram → look for stenosis for surgical intervention (acute limb ischaemia)
4. Duplex Ultrasound Scan (1st line for Intermittent Claudication) → can determine site, severity and length of stenosis
5. Acute Limb Ischaemia (1st investigation) → handheld arterial doppler scan (bedside). And then lower limb angiography (quantify extent of occlusion).
6. Doppler Ultrasound 1st line to identify site of occlusion. CT Angiogram to confirm site of occlusion. ABPI will not give info about occlusion.
7. Buerger’s Test→ lie patient flat on bed and lift up leg to 45º. Limb developing pallor indicates arterial insufficiency. <20º Buerger’s angle indicates severe limb ischaemia. Patient then swings leg over bed, reactive hyperaemia is seen.

Question 10

What scores on the ABPI suggest peripheral vascular disease?

Answer 10

1: Normal
0.6-0.9: Claudication
0.3-0.6: Rest pain
<0.3: critical ischaemia: rest pain, ulceration, gangrene

Question 11

How is chronic PVD managed?

Answer 11

1. Intermittent Claudication
   a. Conservative → smoking cessation, exercise training, avoiding cold temperatures
   b. Medical Therapy → antiplatelet therapy (aspirin + clopidogrel), statins, anti-hypertensives
   - Overall ⇒ Lifestyle measures (exercise) + Clopidogrel 75mg once daily + Atorvastatin 80mg (as secondary prevention) once daily
   - Naftidrofuryl oxalate = vasodilator that can alleviate pain in PVD (if exercise ineffective and patient doesn’t want to be referred for angioplasty or bypass surgery)
   - Refer for endovascular revascularisation or surgical revascularisation when risk factor modification and exercise has not improved symptoms
2. Critical Limb Ischaemia (ie. rest pain, tissue loss, gangrene) → urgent referral to vascular MDT for endovascular revascularisation or surgical revascularisation
   - Endovascular Revascularisation (angioplasty) for small discrete stenosis (<10cm). Surgical Revascularisation (bypass) for larger, more extensive stenosis (>10cm).
   - Amputation → last resort in

Question 12

How is acute peripheral vascular disease managed?

Answer 12

Acute Limb Ischaemia → IV Heparin initially and analgesia + fluids + oxygen. Then refer to vascular surgery (for embolectomy, bypass or amputation). May do angiography to map occlusion and plan treatment.