Ankle-Brachial Index

The Ankle – Brachial Index (ABI) is a ratio of the systolic blood pressure measured simultaneously in the leg and arm. This test is done to screen for peripheral arterial disease (PAD) of the legs.

What the values mean:

• An ABI ratio less than 0.8 implies significant arterial obstruction.
• A ratio of 0.5 or less implies critical obstruction.
• A ratio of < 0.3 implies impending gangrene.
  

Patients with PAD should not wear compression stockings due to high risk of ischaemia.

References:

• Ankle-brachial index test, WebMD
  
• Facts about Intermittent Claudication, North Suburban Cardiology Group