1. What is Ankle-Brachial Index (ABI)?

The Ankle-Brachial Index (ABI) is a simple, non-invasive test that compares the blood pressure in your ankle with the blood pressure in your arm. It's used to screen for peripheral artery disease (PAD) and assess its severity.

2. How Does the Calculator Work?

The calculator uses the ABI formula:

Where:

• Ankle Pressure — Highest systolic pressure from either ankle (mmHg)
• Brachial Pressure — Highest systolic pressure from either arm (mmHg)

Interpretation:

• ABI > 1.3: Possible arterial stiffening
• ABI 0.9-1.3: Normal
• ABI 0.7-0.9: Mild arterial disease
• ABI 0.4-0.7: Moderate arterial disease
• ABI < 0.4: Severe arterial disease

3. Importance of ABI Measurement

Details: ABI is a reliable indicator of peripheral artery disease and can predict cardiovascular risk. It's recommended for patients with leg pain, non-healing wounds, or risk factors for atherosclerosis.

4. Using the Calculator

Tips: Enter the highest systolic pressure from either ankle and the highest systolic pressure from either arm. Both values must be valid (pressure > 0 mmHg).

5. Frequently Asked Questions (FAQ)

Q1: How is ABI measured clinically?
A: Using a blood pressure cuff and Doppler ultrasound to measure systolic pressures at both arms and ankles.

Q2: What's the normal range for ABI?
A: 0.9-1.3 is considered normal. Values below 0.9 suggest PAD.

Q3: Why might ABI be falsely elevated?
A: In patients with non-compressible vessels (e.g., diabetes, calcified arteries).

Q4: When should ABI testing be done?
A: For patients with leg pain when walking, non-healing leg ulcers, or risk factors for PAD.

Q5: Can ABI predict cardiovascular risk?
A: Yes, low ABI is associated with increased risk of heart attack and stroke.