✔ Clinical-style calculator

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Ankle Brachial Index & Toe Brachial Index

Calculated by dividing the systolic pressure of the ankle or toe by the higher systolic pressure of the arms.

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Right Brachial

Systolic (mmHg)

Left Brachial

Systolic (mmHg)

Right Leg

Ankle PT

Ankle DP

Toe Pressure

Left Leg

Ankle PT

Ankle DP

Toe Pressure

Right Side Results

ABI

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TBI

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Left Side Results

ABI

—

TBI

—

Max Brachial:—

Formula: Ankle/Toe ÷ Higher Brachial.

✔ Ankle-Brachial Index (ABI) Interpretation

ABI Value	Interpretation	Clinical Significance
1.00 – 1.40	Normal	Normal arterial flow. No further testing needed unless symptomatic.
0.91 – 0.99	Borderline / Acceptable	May indicate early PAD; consider exercise ABI if symptomatic.
0.71 – 0.90	Mild PAD	Typically asymptomatic or associated with intermittent claudication.
0.41 – 0.70	Moderate PAD	More frequent claudication, reduced walking distance.
≤ 0.40	Severe PAD	Critical limb-threatening ischemia (CLTI); ischemic rest pain, tissue loss.
> 1.40	Non-compressible	Arterial calcification (diabetes, CKD). Unreliable, use TBI.

Source: 2024 ACC/AHA Guidelines for Management of Lower Extremity PAD.

✔ Toe-Brachial Index (TBI) Interpretation

TBI Value	Interpretation	Clinical Significance
≥ 0.70	Normal	Normal arterial flow to the digits.
≤ 0.70	PAD Diagnosis	Diagnostic for Peripheral Artery Disease (PAD).
< 0.30	Severe PAD / Ischemia	Critical limb ischemia; significantly increased risk of non-healing ulcers.

Standard clinical guidelines for TBI interpretation. Often used in cases of medial calcinosis where ABI is unreliable.

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