Ankle-Brachial Index (MESI)

Non-invasive screening for peripheral artery disease and cardiovascular risk

Ankle-Brachial Index (MESI)

Table of contents

Basic data

The Ankle-Brachial Index (ABI) is a simple, non-invasive test that compares blood pressure in the ankle with that in the arm. It helps detect peripheral artery disease (PAD), a condition where narrowed arteries reduce blood flow to the limbs.

Early detection of PAD is important because it may indicate widespread atherosclerosis, which increases the risk of heart attack and stroke. This test is particularly valuable for individuals over 50, smokers, diabetics, and those with high cardiovascular risk.

Category: Lab functional test

Level: Intermediate

Usefulness: Medium

Level

Intermediate

ABI testing can be useful at an intermediate stage of a user’s health journey—especially for those looking to screen for vascular issues or track the impact of lifestyle interventions on circulation. It’s typically not a first-line test but becomes valuable with age or in the presence of other risk factors.

Usefulness

Medium

The ABI test provides fast, accessible insights into cardiovascular and circulatory health.
Early detection of peripheral artery disease (PAD)

Identifies narrowing of the arteries in the legs, which can go undetected for years. PAD increases the risk of heart attack, stroke, and mobility limitations.

Cardiovascular risk assessment

ABI results correlate with overall atherosclerotic burden and can be used alongside cholesterol and blood pressure data to refine CVD risk profiling.

How it works

The ABI is measured using a device that calculates the ratio between blood pressure in the ankle and the arm.
Blood pressure cuffs placed on limbs

Cuffs are applied to the upper arms and ankles. Sensors detect systolic blood pressure at each site.

Ratio is calculated

The ankle pressure is divided by the arm pressure to determine the ABI. Values <0.9 may indicate PAD, while >1.3 could suggest arterial stiffness.

Measures

The ABI test generates a simple but informative set of metrics.
ABI score (right and left leg)

Indicates the presence and severity of peripheral artery disease. Normal range is 1.0–1.4.

Pulse waveforms

Some devices (like MESI) provide waveform quality, which supports assessment of arterial elasticity and signal clarity.

Reliability

ABI testing is highly standardized, though results can vary slightly depending on technique and patient conditions.
Repeatability

With proper technique and equipment, ABI results are reliable and reproducible in most users.

Sensitivity to user state

Cold limbs, recent exercise, or arrhythmias may affect readings. It is best performed in resting conditions.

Limitations

While useful as a screening tool, ABI has some limitations in diagnostic scope.
May miss early-stage PAD

In some cases, the ABI may appear normal even when mild arterial disease is present.

Limited use in people with calcified arteries

Conditions like diabetes or chronic kidney disease can cause falsely elevated ABI due to arterial stiffness.

Frequency

Suggested cadence

For individuals with risk factors, once every 1–2 years may be sufficient. Others may only require screening every few years or when symptoms arise.

Cost

Typical costs

Around $30–$100 USD depending on location and clinic. Some cardiovascular panels include it at no additional charge.

Availability

Where available

Available in many cardiology clinics, vascular labs, and select health screening centers. MESI and similar devices are increasingly common in primary care settings.

Preparation

How to prepare

No special preparation is needed. Avoid intense leg activity immediately before the test to ensure accurate readings.

Interpretation

The results are typically categorized as normal, borderline, or abnormal and may guide follow-up testing or lifestyle interventions.
Normal ABI (1.0–1.4)

Indicates healthy arterial flow. No further testing needed unless symptoms are present.

Borderline (0.91–0.99) or Abnormal (<0.90)

Suggests possible PAD. May warrant additional imaging or referral to a vascular specialist.

Alternatives

Pulse volume recording (PVR)

A more detailed vascular test using waveform analysis and segmental pressures to assess arterial disease.

Doppler ultrasound

Offers more visual detail of arterial flow and blockages, typically used in follow-up to ABI.

FAQ

Can ABI detect heart disease?

ABI does not directly assess the heart, but it is a strong predictor of cardiovascular risk.

Is the test painful?

No — it's completely non-invasive and typically takes under 15 minutes.