Peripheral artery disease symptoms can include aching or cramping in a leg that comes on while walking and eases after you stop. This pattern, called claudication, can point to reduced blood flow, but it does not confirm the cause. A resting ankle-brachial index (ABI) is usually the first test when your symptoms or examination suggest PAD. If the result is normal but walking pain continues, exercise testing or a toe-brachial index may provide useful additional information.
How The Ankle-Brachial Index Is Measured
The ABI compares blood pressure at your ankle with pressure in your arm. You lie down while a clinician places blood-pressure cuffs on your arms and ankles and uses a handheld Doppler device to detect blood flow. For each leg, the higher ankle pressure is divided by the higher arm pressure. The test is non-invasive and usually takes only a short time.
In general, an ABI of 0.90 or lower is abnormal and supports a diagnosis of PAD. A result of 0.91–0.99 is borderline; roughly 1.00–1.40 is considered normal. A reading above 1.40 may mean the arteries are too stiff to compress properly, rather than showing unusually good circulation. Your clinician interprets the number alongside your symptoms and examination, not in isolation.
What Peripheral Artery Disease Symptoms Mean For Testing
Leg discomfort that appears at a fairly repeatable walking distance and settles after a few minutes of rest is a typical pattern of vascular claudication. But PAD can also cause less typical symptoms, or none that you notice. A clinician may ask what brings on the pain, how quickly it eases, and whether changing your posture helps. They may check pulses and look for cool skin, colour changes or foot wounds. These clues guide testing but cannot rule PAD in or out on their own.
If a resting ABI is normal or borderline and you still have exertional leg symptoms, an exercise ABI can help. The clinician measures your ankle pressure before and after walking, often on a treadmill. A drop in pressure after exercise may reveal reduced blood flow that was not apparent at rest. A normal resting result, therefore, does not always settle the question when your symptoms remain suspicious.
When A Toe-Brachial Index May Help
Diabetes and chronic kidney disease can make leg arteries stiff and difficult to compress. This may produce a falsely high ABI, making the test less reliable. When the ABI is above 1.40 or the arteries appear non-compressible, a toe-brachial index (TBI) may be used instead. It compares pressure in a toe with pressure in the arm. Toe arteries are less likely to become stiff in the same way, so the TBI can help assess blood flow when an ankle reading is hard to interpret. Your clinician may also consider other vascular tests depending on the findings and whether a wound needs assessment.
What Happens After A PAD Diagnosis
Assessment usually includes your medical history, risk factors, a leg examination and the test results. If more detail is needed—particularly before considering a procedure—ultrasound or other imaging may help locate narrowed arteries. The 2024 US ACC/AHA guideline describes care that addresses both walking ability and cardiovascular risk. Depending on your situation, this may include structured exercise, smoking cessation support and clinician-directed treatment for cholesterol, blood pressure, diabetes or clot risk. Revascularisation, using an endovascular procedure or surgery, may be considered when symptoms continue to limit daily life despite initial care, or when blood flow is seriously threatening the limb. Local pathways and treatment availability differ between countries.
A diagnosis does not automatically mean you need a procedure. It helps your care team judge what may be causing your symptoms and discuss options suited to your health and goals. If you have diabetes or kidney disease, mention it when arranging an assessment, since it can affect how ABI results are interpreted.
Symptoms That Need Urgent Care
Seek emergency care for sudden, severe leg or foot pain, especially if the limb becomes cold, pale or numb, or you develop weakness or difficulty moving it. These can be signs of an abrupt loss of blood flow. A new or worsening foot wound, blackened tissue, or persistent pain in the foot at rest also needs prompt medical assessment. If you are unsure how quickly to seek care, contact a clinician or emergency service rather than waiting for a routine ABI appointment.
If walking pain keeps returning, arrange a clinical assessment rather than relying on a normal pulse check or a single resting test. A clinician can decide whether an ABI, exercise testing or a toe-pressure test is the right next step.
