Peripheral artery disease resident survival guide

Resident Survival Guide
Introduction
Team
Guide
Page Template
Examine the Patient Template
Navigation Bar Template
Checklist
Topics

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: José Eduardo Riceto Loyola Junior, M.D.[2]

Overview

Claudication is the description of cramping muscle pain that occurs after a certain degree of exercise and is relieved by rest. Claudication is classically caused by peripheral arterial disease, in which an obstruction in artery of the lower limbs can lead to an insufficient blood flow which is not enough to supply the demands from the muscles of that region, but there are other conditions that can mimic its symptoms such as nerve root compression, spinal stenosis, hip arthritis, symptomatic Baker's cyst, venous claudication and chronic compartment syndrome.

Causes

Life Threatening Causes

There are no life-threatening causes, which include conditions which may result in death or permanent disability within 24 hours if left untreated.

Common Causes

• Peripheral arterial disease
• Venous claudication
• Arterial thromboembolism
• Cholesterol embolism
• Vasculitis
• Nerve root compression (radiculopathy, plexopathy)
• Peripheral neuropathy
• Lumbar canal stenosis (pseudoclaudication)
• Spinal stenosis
• Arthritis/Connective tissue disease
• Baker's cyst
• Muscle strain
• Ligament/tendon injury
• Chronic compartment syndrome

Diagnosis

Shown below is a table summarizing the diagnosis of peripheral arterial disease:

Suspected PAD

Symptoms: ❑ Leg pain at rest ❑ Reduced or absent pulses ❑ Leg pain during exertion ❑ Gangrene ❑ Pale extremity ❑ Non healing wound ❑ Calf or foot cramping ❑ Paresthesias

Order Ankle brachial index

≤ 0.90

Normal 0.91-1.30

> 1.30

Order Exercise ABI

Order Toe-Brachial Index OR Pulse volume recording OR Duplex ultrasound

Does the patient have > 20% decrease in Postexercise ABI?

Is TBI < 0.7?

Yes

No

No

Yes

PAD confirmed

No PAD

PAD confirmed

Shown below is a table summarizing the differential diagnosis of claudication according the age and clinical presentation:

Differential Diagnosis of Intermittent Claudication and Lower Limb Pain

In younger patients:
Diagnosis	Clinical Features	Diagnostic Method of Choice	Treatment
Buerger's Disease	Rare vasculitis mostly seen in young Asians males who are smokers. Causes inflammation and thrombosis of the arteries of the legs, feet, forearms, and hands.	Conventional angiography - multilevel occlusions and segmental narrowing of the lower extremity arteries with extensive collateral flow showing a corkscrew or “tree root” appearance	Smoking cessation
Extrinsic Compression by Bone Lesions	Not a common cause, 40% of osteochondromas arise from the posterior aspect of distal femur compressing the femoral artery.	MRI, limb x-ray or CT scan	Excision of the lesion and repair of the affected artery
Popliteal Artery Entrapment Syndrome	Common in young patients with claudication, especially athletes - compression of the popliteal artery by the medial head of the gastrocnemius muscle.	Stress angiography	Surgery
Fibromuscular Dysplasia	Affects young women of childbearing age, affects mostly renal, cerebral and visceral arteries but may affect limbs as well.	Angiography - string-of-beads appearance	Angioplasty
Takayasu's Arteritis	Rare vasculitis mostly seen on Asian and South American women. Stenosis of the abdominal aorta and iliac arteries are present in 17% of the patients and may cause claudication.	Conventional angiography	Corticosteroids, methotrexate, azathioprine, and cyclophosphamide
Cystic Adventitial Disease	1 in 1200 cases of claudication, most common in men, 20-50 years without risk factors for atherosclerosis. It is caused by repetitive trauma, which causes the formation of a mucin-containing cystic structure in the wall of the popliteal artery.	Conventional angiography, MRI	Complete excision of the cyst with prosthetic and vein replacement, as well as bypass
In older patients:
Spinal Stenosis	Motor weakness is the most important symptom, which may be accompanied by pain. It starts soon after standing up, and may be relieved by sitting or bending (lumbar spine flexion)	MRI	Analgesic drugs, physical therapy, acupuncture or surgery (gold standard)
Peripheral Arterial Disease	May present with absent or reduced peripheral pulses, and audible bruits but some patients may not present with these symptoms. A low ankle-brachial pressure index (<0.9) is suggestive of the disease but if normal it does not exclude it. An exercise ankle-brachial pressure index can be done on patients that doesn't present with these signs. Other clinical features include: decreased skin temperature, shiny, hairless skin over the lower extremities, pallor on elevation of the extremity, dystrophic toenails, and rubor when the limb is dependent.	Handheld Doppler, conventional angiography	Smoking cessation, antiplatelet drugs, statins, diabetes and blood pressure control, exercise, percutaneous transluminal angioplasty.
Nerve Root Compression	Caused by compression of the nerve root by other structure, such as an herniated disc. The pain usually radiates down the back of the leg and is described as sharp lancinating pain. It may be relieved by adjusting the position of the back (leaning forward).	MRI	Surgery
Hip Arthritis	Pain starts when the patient undergoes weight bearing and is worsened by activity. The pain is continuous and intensified by weight bearing, with inflammatory signs such as tenderness, swelling, and hyperthermia.	MRI	Surgery
Baker's Cyst	Pain is worsened with activity, not relieved by resting, and may have tenderness and swelling behind the knee.	Ultrasound, MRI	Surgery

Treatment

Shown below is an algorithm summarizing the diagnosis of claudication due to peripheral arterial disease according the the British Medical Journal guidelines.

Evaluate affected limb - check for color and trophic changes, early ulcerations, skin temperature, capillary refill time, pulses at the groin and popliteal fossa, and the pedal pulses.

If peripheral arterial disease is suspected: Screening test: ankle-brachial index (systolic blood pressure of the dorsalis pedis, posterior tibialis, or fibularis artery is obtained with a handheld Doppler and divided by the higher of the two brachial pressures) - if <0.9 confirms peripheral arterial disease.

Secondary prevention for coronary arterial disease: start aspirin 75mg daily and statins

Control cardiovascular risk factors (hyperglycemia, obesity, dyslipidemia, smoking)

Advise the patient to exercise for 30 minutes twice daily to increase pain-free walking and total walking distance by stimulating collateral blood flow)

Pentoxifylline may be used for improving symptoms, but the preferred drug is Cilostazol

Be aware of the 5 Ps—pain, pale, pulseless, paraesthesia, paralysis—indicating an acute limb ischemia

Do's

• Assess for peripheral arterial disease, as it is the most common cause for intermittent claudication, but do consider other causes depending on the age;
• Confirm the diagnosis by measuring the ankle-brachial pressure indices;
• Assess the risk factors for atherosclerosis and control them. Encourage patients to cease smoking, to control the blood glucose, prescribe antiplatelet drugs, optimize antihypertensive medication doses, start statins and encourage exercise;
• If there's no improvement, symptoms are disabling or diagnosis is uncertain, refer to a specialist.
• Best treatment options for peripheral arterial disease are: open surgery, endovascular therapy, and exercise therapy. These were superior to medical management in achieve higher walking distance and managing claudication.

Don'ts

• Symptomatic treatment of the claudication and leg pain must not overshadow the reduction of cardiovascular risk, as these patients have a significantly increased risk of death.
• When treating peripheral arterial disease, always attempt reducing symptoms with less invasive treatment options such as exercising, do not immediately refer patients to more invasive treatment options;
• Don't forget to address other causes of claudication if the patient is presenting it at a younger age, or if the treatment doesn't improve the symptoms.

References

Template:WikiDoc Sources