How do you differentiate between peripheral venous disease (PVD) and peripheral arterial disease (PAD) in a patient with symptoms of peripheral vascular disease?

Differentiating Peripheral Arterial Disease (PAD) from Peripheral Venous Disease (PVD)

PAD and peripheral venous disease are distinguished primarily by their symptom patterns, physical examination findings, and ankle-brachial index (ABI) testing—with PAD causing exercise-induced muscle pain that resolves quickly with rest and diminished pulses, while venous disease causes aching/heaviness that worsens with standing and improves with elevation, with normal pulses present. 1

Clinical Presentation: The Key Differentiator

PAD Characteristics

• Claudication pattern: Fatigue, discomfort, or pain in buttocks, thigh, or calf muscles during exercise that is quickly relieved by rest within 10 minutes 1, 2
• Location depends on occlusion level: Buttocks (aortoiliac), thigh (common femoral), calf (superficial femoral/popliteal) 1
• Important caveat: Only one-third of PAD patients present with typical claudication; most have atypical exertional leg symptoms or are asymptomatic 2

Venous Insufficiency Characteristics

• Pain pattern: Aching, heaviness, and throbbing that worsens with prolonged standing and improves with leg elevation 1, 2
• Timing: Pain often present at rest, not specifically exercise-induced 2
• Venous claudication (severe form): Tight, bursting pain in entire leg (worse in calf) after walking that subsides slowly and requires leg elevation for relief 2

Physical Examination Findings

PAD Physical Signs

• Pulse examination: Diminished or absent pulses (femoral, popliteal, dorsalis pedis, posterior tibial) rated 0-3 scale 2, 1
• Skin changes: Pallor on elevation, delayed capillary refill (>3 seconds), cool extremities, hair loss, atrophic skin 1, 2
• Ulcer location: Typically on toes, foot, or pressure points 1
• Vascular bruits: Femoral or abdominal bruits may be present 2
• Elevation pallor/dependent rubor: Classic finding in severe PAD 2

Venous Insufficiency Physical Signs

• Pulse examination: Normal pulses present—this is the critical distinguishing feature 1, 2
• Edema: Present, particularly with prolonged standing 1, 2
• Skin changes: Hyperpigmentation, lipodermatosclerosis, varicose veins 1
• Ulcer location: Typically medial malleolus (gaiter area) 2

Diagnostic Algorithm

Step 1: Initial Assessment

• Perform comprehensive pulse examination bilaterally (brachial, radial, ulnar, femoral, popliteal, dorsalis pedis, posterior tibial) 1
• Critical pitfall: Never assume leg pain is venous without checking pulses and ABI—missing PAD can lead to limb loss 1

Step 2: ABI Testing for Suspected PAD

• ABI <0.90 confirms PAD (75% sensitivity, 86% specificity) 1, 2
• ABI >1.40 suggests non-compressible arteries (arterial calcification); obtain toe-brachial index (TBI) 1
• TBI <0.70 confirms PAD when ABI unreliable (common in diabetics, elderly) 1

Step 3: Duplex Ultrasound

• For PAD: First-line imaging to confirm and localize arterial lesions 1, 2
• For venous disease: Assesses venous reflux and obstruction 1

Step 4: Consider Mixed Disease

• 15-20% of patients have both PAD and chronic venous insufficiency, requiring combined management strategies 1
• If venous symptoms present but pulses abnormal or ABI <0.90, evaluate for both conditions 1

Common Diagnostic Pitfalls

Misdiagnosis Risks

• Assuming venous etiology without pulse/ABI assessment is the most dangerous error 1
• Relying solely on symptom description: PAD symptoms are highly variable—70% of patients lack classic claudication 2
• Missing asymptomatic PAD: Up to 50% of PAD patients are asymptomatic but still at high cardiovascular risk 2, 3

Differential Diagnosis Considerations

When symptoms don't fit PAD or venous patterns, consider 2:

• Spinal stenosis: Bilateral buttock/leg pain, relief with lumbar flexion, worse with standing
• Hip/ankle arthritis: Variable exercise tolerance, not quickly relieved by rest
• Nerve root compression: Sharp lancinating pain, often present at rest
• Chronic compartment syndrome: Tight bursting pain after strenuous exercise, very slow resolution

Management Implications Based on Diagnosis

If PAD Confirmed

• Cardiovascular risk reduction is paramount: LDL-C <55 mg/dL, antiplatelet therapy, smoking cessation 1, 2
• Supervised exercise therapy: 3x/week, 30+ minutes, 12+ weeks minimum 4, 2
• Revascularization: Only after 3-month trial of optimal medical therapy and exercise for persistent lifestyle-limiting symptoms 4, 2

If Venous Insufficiency Confirmed

• Compression therapy, leg elevation, treatment of underlying venous obstruction 1
• Consider iliac vein stenting for May-Thurner syndrome or post-thrombotic obstruction 1