Ankle-brachial pressure index

The ankle-brachial pressure index is calculated by:

ABPI = (ankle systolic BP)/(brachial systolic BP)

Interpretation of results is not entirely straightforward as various consensus papers give different cut -offs for the definitions of 'moderate' and 'severe'.  One set of definitions is:
  • >1.4: calcification may be present
  • >1.0 probably no arterial disease
  • 0.81-1.0 no significant arterial disease
  • 0.5-0.8 moderate disease
  • <0.5 severe disease
  • <0.3 critical ischaemia

It is worth noting that an ABPI <0.9 or of >1.4 is an independent risk factor for cardiovascular disease.

ABPI may be non-diagnostic in patients with heavy arterial calcification, such as:
  • diabetics (5-10% of diabetic patients cannot have their occlusive ankle pressure measured)
  • the elderly
  • renal failure

author profile image

Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.

Secret collector of interesting anonymised ECGs. Fan of the Bath Photomarathon. Lover of cream teas. [Sarah Hudson] (Your Picture)