Intermittent Claudication

occurs when arterial blood flow is insufficient to meet the metabolic demands of resting muscle or tissue

The natural history of limb-threatening ischemia usually involves inexorable progression to amputation unless there is an intervention that results in the improvement of arterial perfusion.

This is in contrast to the often benign natural history of mild and moderate claudication

The major manifestations of limb-threatening ischemia 

1. rest pain
2. ischemic ulcers
3. gangrene 

CLINICAL PRESENTATION

• Presents with symptoms of leg ischemia.
• Asymptomatic — 20 – 50%
• Symptomatic disease
  • the perception of claudication can vary from severe debilitating discomfort at rest to a bothersome pain of seemingly little consequence. 
  • Severity of symptoms of claudication depends upon the amount of stenosis, the collateral circulation, and the vigor of exercise. 
• Atypical leg pain — 40 – 50%
• Classic claudication — 10-35%
• Critical limb ischemia — 1 – 2% 

Differential diagnosis of claudication
			Patient characteristics	Clinical features
Arterial occlusion or narrowing	Vasculitides	Takayasu arteritis	Asian females 15–45 years	Fever, Malaise. Arthralgia. Syncope, angina pectoris, Impaired vision
		Thromboangiitis obliterans	20–40 years   More common in males before the age of 45 years ] Significant history of cigarette smoking	Migratory thrombophlebitis   Intermittent claudication , often limited to feet, calves and/or hands Raynaud syndrome
	(Lower-extremity)    fibromuscular dysplasia		Middle-aged women	Gradual onset of symptoms   Rarely affects the extremities, leading to intermittent claudication, CLI, and  blue toe syndrome
	Popliteal aneurysm		Similar risk factors as    PAD	Chronic lower limb  ischemia    may manifest like  PAD  ALI  (6 Ps) Blue toe syndrome: small vessel occlusion caused by  embolus
	Arterial embolism		Young patients without    atherosclerotic risk factors	Sudden onset of symptoms   6 Ps
	Popliteal entrapment syndrome		Most commonly affects young men < 30 years	Intermittent claudication
	Cystic adventitial disease		Generally affects men between 30–50 years	Foot pulses may be present during rest and absent following exercise
Mimics of arterial occlusion	Deep vein thrombosis		> 60 years old   History of immobilization,  obesity, hereditary thrombophilia  or  malignancy	Swelling   Warmth Erythema Progressive tenderness Dull pain: worsened by walking, improved by resting
	Spinal stenosis		Middle-aged to older patients	Neurogenic claudication   Accompanied by weakness or numbness Bilateral or unilateral leg and back pain Improved with lumbar flexion
	Diabetic neuropathy		Middle-aged to older patients High BMI	Progressive symmetrical loss of or abnormal sensation in the distal lower extremities (glove and stocking sensation)   Normal  ABI Neuropathic diabetic foot: warm, dry skin, palpable foot pulses

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History

Pain of Intermittent claudication

• Caused by walking
• Starts as ache→↑’s in severity→ forces pt to stop walking
• Relieved by rest
• NO pain at rest
• Always felt in the muscles(pain is due to anoxia and lactic acidosis due to anaerobic metabolism)
• Distance a pt can walk depends on:

• Rate of walking
• Level of incline
• Degree of arterial obstruction
• Development of collateral circulation

Rest Pain

• Occurs in lest well perfused areas of the leg: over the toes and forefoot
• Pain is severe, aching in nature, wakes from patient from sleep
• Precipitated by: lying down flat/night
• Relieved by getting up and walking on a cold floor, hanging to the foot over the edge

Risk Factors 

• Smoking
• Hypertension
• Dyslipidaemia
• Diabetes mellitus
• Hyperhomocysteinaemia
•  

Other important comorbidities

• Ischaemic Heart Disease
• Cerebrovascular Disease – TIA/Stroke
• Diabetes Mellitus
• Renal circulation – HT
  

Site of pain- depends on site of obstruction:

site of pain	site of disease
Buttock and hip   (Leriche’s syndrome)	aortoiliac disease	Claudication of hip, thigh and buttock mm, Aching in nature , atrophy of leg mm severe bilateral aortoiliac disease 🡪almost always causes impotence in men ↓’d/absent femoral pulsesDDx:
OA hip/knee	Neurogenic claudication
OA Pain occurs mostly in jts   may not disappear promptly after exercise may vary in intensity from day to day.	due to lumbar neurospinal canal compression (osteophytic narrowing). causes pain with erect posture (lordosis) and is relieved by sitting or lying down.   symptomatic relief by leaning forward and straightening the spine (usually done with pushing a shopping cart or leaning against a wall)
Thigh	common femoral artery or aortoiliac
Upper two-thirds of the calf	superficial femoral artery	Calf claudication is the most common complaint.  Cramping pain reproduced with exercise and relieved with rest.  DDx Nocturnal leg cramps occur among older and infirmed patients. neuromuscular rather than vascular in origin. Calf pressure and tightness primarily seen in athletes (due to increased compartment pressure and may persist even after rest)
Lower one-third of the calf	popliteal artery
Foot claudication	tibial or peroneal artery	Isolated foot claudication is rarely seen with atherosclerotic occlusive disease  but is commonly seen with thromboangiitis obliterans (Buerger’s disease).

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On Examination

General Inspection

• Pallor
• Loss of hair of dorsum of toes/foot
• Hyperkeratosis of nails
• Atrophy of skin/subcutaneous tissue→shiny, scaly skin
• Temperature
• Ulcers – gen. very painful – occur on pressure areas e.g. ball of foot, heel, toes – sharply punched out, no granulation tissue
• May notice muscle atrophy/↓ strength

Pulses/Arterial palpation

• ↓’d capillary return
• Hard/rubbery arteries
• ↑’d pulses = proximal stenosis
• N.B. unusual for collateral flow to produce a pulse distal to an OCCLUDED artery

Bruits

• Loudest in systole. Transmitted distally along course of artery ∴ stenosis is present at or proximal to level at which bruit is heard

Other

Full CVS, neuro examination 

Buerger’s test –

1. patient made supine
2. Both legs are examined simultaneously 
3. elevate both legs to an angle 
4. Observe the color of the feet. 
5. 🡪 at some point the leg becomes White/Pallor and indicates ischaemia.
   • Peripheral arterial pressure is inadequate to overcome the effects of gravity. 
   • poorer the arterial supply, the less the angle to which the legs have to be raised(20o = severe ischemia) 
6. sit the patient up and ask them to hang their legs down over the side of the bed at an angle of 90 degrees. 
   • Gravity aids blood flow and colour returns in the ischaemic leg. 
7. First Skin becomes blue
   • as blood is deoxygenated in its passage through the ischaemic tissue
8. Then dusky Red flush

• Due to reactive hyperaemia from post-hypoxic vasodilatation

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Investigations

• BSL
• Cholesterol
• FBC – anaemia can be a precipitant
• UEC – check renal function
• ECG – evidence of ischaemia
• Other investigations to assess cardiovascular/cerebrovascular integrity as appropriate
• Doppler ultrasonography/ABI
• ABI >0.7→conservative management
• ABI <0.7→vascular evaluation
• Invasive diagnostic testing – usually not needed if diagnosis of intermittent claudication is clear-cut

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Management

Social impact

• Impact on patient’s life
• Work, sleep, going to shops, walking aids?

General Measures

• Foot/skin/nail care – podiatry, appropriate footwear etc.
• Early treatment of infection
• Avoid elastic compression stockings
• Avoid vasoconstrictive influences e.g. β-blockers
• Correct precipitants e.g. anaemia

Risk Factor Modification

• Lifestyle modification, weight reduction
• Strict control of diabetes, complications
• Treatment of hypertension, hyperlipidaemia
• Cessation of smoking

Regular Exercise

• Graded exercise program→improves collateral circulation→improves maximal walking distance (30-60min per day or every 2nd day)

Foot care

• Patients with diabetes and PAD are at increased risk of diabetes-related foot ulceration.
• Perform regular 1–3-monthly foot checks during all routine clinical appointments.
• Include regular podiatry review in care plans to manage pre-ulcerative lesions such as heel callus, fissures or thickened nails as indicated.
• Therapeutic footwear and accommodative orthoses are recommended to be fitted by trained podiatrists, orthotists or pedorthotists.
• Early referral to both a vascular surgeon and specialised interdisciplinary care, such as a high-risk foot service, is recommended when tissue loss is identified.
• Arrange urgent hospital assessment for patients with diabetes and suspected sepsis due to foot ulceration.

Management of Associated Disorders

• A/ment of coronary, carotid, renal circulations
• Assignment to risk group for these disorders

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Pharm. Treatment

antiplatelet therapy 

• Single-agent antiplatelet therapy (with aspirin 100–150 mg or clopidogrel 75 mg daily) is recommended for symptomatic patients, or following intervention.
• Some patients may require dual antiplatelet therapy for a period (up to six months) after peripheral endovascular intervention or stenting.
• Dual pathway inhibition with aspirin (100 mg daily) and low-dose rivaroxaban (2.5 mg twice daily) may be indicated for high-risk patients
• Anticoagulation (with warfarin or DOAC) is not indicated for PAD treatment.
• For patients who require long-term anticoagulation for other indications (eg atrial fibrillation), antiplatelet therapy is generally not required.
• Ticagrelor is not indicated for treatment of PAD.

Antihypertensive therapy

• Aim for blood pressure control of <140/80 mmHg in all patients with hypertension and PAD.
• ACEIs or ARBs are considered first-line antihypertensive therapy in PAD.
• Beta-blockers are not contraindicated but should be used with caution for patients with CLTI.

Lipid-lowering therapy

• Statins are indicated for all patients with PAD, irrespective of serum cholesterol levels.
• Lower LDL-C to <1.8 mmol/L or decrease by 50% if baseline is 1.8–3.5 mmol/L.
• Prescribe the highest dose of statins tolerated to achieve LDL-C targets.
• Combination therapy with ezetimide may be required.
• Evidence for alternative, non-statin lipid-lowering agents is limited.

Glycaemic control

• Aim for tight glycaemic control in patients with diabetes and PAD.2
• Exercise caution when prescribing SGLT-2 inhibitors to patients with PAD because of the increased risk of amputation in some studies.28

Revascularisation

• Most patients with intermittent claudication, except for those with critical limb ischemia, are treated initially with medical therapy. 
• criteria for revascularization 

1. Severe disability that limits the patient’s ability to work or to perform other activities that are important to the patient
2. Failure (or predicted failure) to respond to exercise rehabilitation and pharmacologic therapy.

• Angioplasty/other endoluminal techniques
• Bypass graft surgery or endarterectomy