Peripheral Artery Disease: Symptoms and Screening

Peripheral artery disease affects more than eight million Americans, making it one of the most common cardiovascular conditions in the country.^[1] It is also one of the most underdiagnosed. Unlike heart disease, which commands significant awareness and public health attention, PAD develops quietly in the legs and is frequently dismissed as normal aging, arthritis, or being out of shape. By the time a definitive diagnosis is made, the disease is often significantly advanced.

What Peripheral Artery Disease Actually Is

PAD is atherosclerosis of the lower extremity arteries. The same plaque-building process that narrows coronary arteries and carotid arteries also affects the arteries supplying the legs: the aorta, iliac arteries, femoral arteries, popliteal arteries, and tibial arteries. As these vessels narrow, blood flow to the legs during exertion becomes inadequate, and in severe cases, blood flow is insufficient even at rest.

PAD is not an isolated leg problem. It is a systemic marker of atherosclerotic burden throughout the body. People diagnosed with PAD have a two to three times higher risk of heart attack and stroke compared to the general population.^[2] PAD is classified as a coronary artery disease risk equivalent, meaning its presence automatically places a patient in the highest cardiovascular risk category regardless of other factors.

Symptoms: What People Miss and Why

Classic PAD presents as claudication: cramping or aching pain in the calf, thigh, or buttock that begins with walking and resolves within minutes of rest. This symptom pattern is pathognomonic of reduced arterial flow during exercise. However, fewer than 20 percent of PAD patients experience classic claudication.^[1] Many have atypical leg symptoms they attribute to arthritis, muscle fatigue, or age. Many more are completely asymptomatic.

The Ankle-Brachial Index and Duplex Ultrasound

The ankle-brachial index compares blood pressure at the ankle to blood pressure at the arm. An ABI below 0.9 indicates reduced flow consistent with PAD.^[3] However, ABI can be falsely elevated in diabetic patients with calcified, incompressible vessels, making direct duplex ultrasound imaging essential for complete evaluation.

Lower extremity arterial duplex ultrasound directly visualizes the arteries from the aortic bifurcation to the tibial vessels. It identifies the location, length, and severity of stenoses, distinguishes occlusion from stenosis, and provides flow velocity data that quantifies the hemodynamic significance of each lesion. This information guides intervention planning.

Risk Factors and Who Should Be Screened

Several factors sharply increase PAD risk, and guidelines recommend screening anyone who has them, even without symptoms. Age over 50 combined with any smoking history, diabetes, long-standing hypertension, high cholesterol, chronic kidney disease, and known coronary artery disease all qualify. Unexplained leg pain, slow-healing wounds, or one leg that feels colder than the other should also prompt screening regardless of age.

• ›Age over 50 with smoking history of any duration
• ›Diabetes mellitus, which dramatically accelerates lower extremity arterial disease
• ›Hypertension over multiple years
• ›High cholesterol or known coronary artery disease
• ›Chronic kidney disease
• ›Unexplained leg pain, wounds that heal slowly, or coldness in one leg compared to the other

Why Early Diagnosis Changes Outcomes

Early diagnosis changes outcomes because PAD is far easier to manage before it progresses. Asymptomatic or mildly symptomatic PAD responds to antiplatelet therapy, statin therapy, blood pressure control, smoking cessation, and supervised exercise, while advanced PAD often requires revascularization. The window between early PAD and critical limb ischemia, the stage where amputation becomes a real possibility, can span years — catching it early is the difference between medical management and limb salvage surgery.