How should a patient with suspected Peripheral Artery Disease (PAD) and leg pain be treated in the outpatient primary care setting, according to American Heart Association (AHA) and other clinical guidelines?

Management of Suspected PAD with Leg Pain in Primary Care

All patients with suspected PAD and leg pain should undergo resting ankle-brachial index (ABI) measurement as the initial diagnostic test, followed by immediate initiation of guideline-directed medical therapy including antiplatelet therapy (aspirin 75-325 mg daily or clopidogrel 75 mg daily), high-intensity statin therapy, and structured exercise therapy regardless of whether revascularization is planned. 1

Initial Clinical Evaluation

History and Physical Examination

• Document specific leg pain characteristics: location, quality, relationship to exertion, time to onset with walking, and time to resolution with rest 1, 2
• Assess for classic claudication (reproducible leg pain with predictable walking distance that resolves within 10 minutes of rest) versus atypical leg symptoms 1, 2
• Screen for critical limb ischemia features: rest pain, non-healing wounds, gangrene, or tissue loss 1, 2
• Palpate all lower extremity pulses (femoral, popliteal, dorsalis pedis, posterior tibial) and grade as 0 (absent), 1 (diminished), 2 (normal), or 3 (bounding) 1
• Auscultate for femoral bruits 1
• Inspect legs and feet for skin changes, hair loss, ulceration, or color changes 1
• Measure blood pressure in both arms to identify >15-20 mm Hg difference suggesting subclavian stenosis 1

Risk Factor Documentation

Target patients at increased risk: age ≥65 years, age 50-64 with atherosclerotic risk factors (diabetes, smoking history, hyperlipidemia, hypertension), or age <50 with diabetes plus additional risk factor 1, 2

Diagnostic Testing Algorithm

Resting ABI (First-Line Test)

• Perform resting ABI with or without segmental pressures in all patients with history or physical examination findings suggestive of PAD 1
• Measure systolic blood pressures at brachial arteries and both ankle arteries (dorsalis pedis and posterior tibial) using Doppler 1
• Calculate ABI by dividing the higher ankle pressure by the higher arm pressure for each leg 1

ABI Interpretation and Next Steps

• ABI ≤0.90 = Abnormal (confirms PAD diagnosis) - proceed to medical therapy 1, 2
• ABI 0.91-0.99 = Borderline - consider exercise treadmill ABI testing if symptomatic 1
• ABI 1.00-1.40 = Normal - if exertional leg symptoms persist, perform exercise treadmill ABI testing 1, 2
• ABI >1.40 = Noncompressible arteries - measure toe-brachial index (TBI) instead 1, 2

Critical pitfall: Diabetic patients and those with chronic kidney disease frequently have noncompressible arteries; do not rely on ABI alone in these populations 2

Exercise Treadmill ABI Testing

• Indicated when resting ABI is normal or borderline (>0.90 and ≤1.40) but exertional leg symptoms persist 1, 2
• Also useful in patients with abnormal ABI (≤0.90) to objectively assess functional status and document symptom severity 1

Anatomic Imaging

• Do not obtain anatomic imaging (duplex ultrasound, CTA, MRA, or angiography) unless revascularization is being considered 1, 2
• Reserve duplex ultrasound, CTA, or MRA for symptomatic patients with inadequate response to guideline-directed medical therapy who are revascularization candidates 1

Guideline-Directed Medical Therapy (Initiate Immediately Upon Diagnosis)

Antiplatelet Therapy (Class I Recommendation)

Prescribe either aspirin 75-325 mg daily OR clopidogrel 75 mg daily to reduce myocardial infarction, stroke, and vascular death 1

• Clopidogrel is preferred based on contemporary evidence 3
• Dual antiplatelet therapy (aspirin plus clopidogrel) is not well established for routine use in symptomatic PAD 1

Statin Therapy (Class I Recommendation)

All patients with PAD must receive high-intensity statin therapy regardless of baseline lipid levels 1, 4

• This reduces cardiovascular ischemic events and may improve leg symptoms 1, 4

Antihypertensive Therapy (Class I Recommendation)

Administer antihypertensive therapy to patients with hypertension and PAD to reduce myocardial infarction, stroke, heart failure, and cardiovascular death 1

• ACE inhibitors or ARBs are reasonable choices (Class IIa) as they may provide additional benefits beyond blood pressure control 1, 4

Structured Exercise Therapy (Class I Recommendation)

Prescribe supervised exercise program as first-line therapy for claudication 1

• Minimum 30-45 minutes per session, at least 3 times weekly for minimum 12 weeks 1
• Involves intermittent walking to moderate-to-maximum claudication, alternating with rest periods 1
• Supervised programs in hospital/outpatient facilities are preferred, but structured community or home-based programs with health coaching are acceptable alternatives 1
• Exercise improves walking distance, quality of life, and may delay disease progression 4, 5

Cilostazol for Claudication Symptoms

Consider cilostazol 100 mg twice daily for treatment of leg symptoms and walking impairment due to claudication 1

• Effective for improving walking distance but has side effects (headache, diarrhea, dizziness, palpitations) 1
• Approximately 20% discontinuation rate within 3 months 1

Smoking Cessation (Essential Component)

Smoking cessation is vital for all patients with PAD who smoke 1, 6, 4

• Utilize physician counseling, nicotine replacement therapy, and/or bupropion 4

Diabetes Management

Optimize glycemic control with preference for GLP-1 receptor agonists and SGLT-2 inhibitors when applicable 3

Screening for Associated Conditions

Abdominal Aortic Aneurysm Screening

Screening duplex ultrasound for AAA is reasonable in patients with symptomatic PAD, particularly those ≥55 years 1

Do Not Screen for Asymptomatic Disease in Other Arterial Beds

Routine screening for asymptomatic coronary, carotid, or renal artery disease is not indicated 1

• Intensive risk factor modification through guideline-directed medical therapy is the primary method for preventing events from disease in other arterial beds 1

Red Flags Requiring Urgent/Emergency Referral

Patients with acute limb ischemia symptoms (sudden onset severe pain, pallor, pulselessness, paresthesias, paralysis, poikilothermia) require immediate vascular specialist evaluation within <6 hours 1, 2

Patients with critical limb ischemia (rest pain, non-healing wounds, gangrene) require urgent interdisciplinary vascular team evaluation within 6-24 hours 1, 2

Critical pitfall: Diabetic patients with CLI may have no pain due to neuropathy but still have severe tissue loss requiring urgent evaluation 2

Follow-Up and Revascularization Consideration

• Reassess response to guideline-directed medical therapy and structured exercise at 3-6 months 1
• Consider revascularization referral only for patients with lifestyle-limiting claudication despite optimal medical therapy or those with critical limb ischemia 1
• Obtain anatomic imaging (duplex ultrasound, CTA, or MRA) only when revascularization is being actively considered 1, 2