Ankle Brachial Pressure Index (ABI or ABPI)

ABI is a non-invasive test for the assessment of Peripheral Vascular Disease (PVD). Research studies have demonstrated that the sensitivity of ABPI is 90% with a corresponding specificity of 98% when used to detect hemodynamically significant stenosis (>50% stenosis in major leg arteries, defined by angiogram).

ABILeg = PLeg/PArm

Where PLeg is the systolic blood pressure at the dorsalis pedis / posterior tibial arteries and PArm is the highest systolic pressure of the left and right arm brachial arteries.

Why should I measure my patients ABI?

The ABI test is a highly cost effective method of screening patients for Peripheral Vascular Disease and the onset of Peripheral Vascular Disease. The equipment is quick and easy to use. A high ankle-brachial index is associated with increased cardiovascular disease morbidity and lower quality of life[2]

Why should I buy an iHealth ABI Device?

An ABI value is traditionally determined using a Doppler ultrasound flow detector together with a sphygmomanometer (blood pressure cuff). The doppler ultrasound flow detector is used to register the peripheral pulse while the sphygmomanometer is inflated until the pulse ceases. The cuff is slowly deflated, and the corresponding sphygmomanometer pressure at the instant the pulse returns, provides the systolic blood pressure reading, for the given artery.

  1. Performing ABI using Doppler ultrasound is time consuming
  2. Lack of protocol standardisation reduces inter-operative reproducibility
  3. Skilled Operators are required for consistent, accurate results

The iHeath ABI device developed by Uwe Diegal and Roland Asmar uses an oscillometric method, employing simultaneous measurement at the ankle and upper arm using specially calibrated oscillometric modules. A reliable ABI measurement can be carried out in under 3 minutes by any doctor.

What other useful measurements can an iHealth ABI device determine?

The iHealth ABI device can be used to determine both stroke volume and cardiac output

ABI (ABPI) interpretation, action & treatment

ABPI value Interpretation Action Nature of ulcers, if present
above 1.2 Abnormal
Vessel hardening from PVD
Refer routinely Venous ulcer
use full compression bandaging
1.0 - 1.2 Normal range None  
0.9 - 1.0 Acceptable    
0.8 - 0.9 Some arterial disease Manage risk factors  
0.5 - 0.8 Moderate arterial disease Routine specialist referral Mixed ulcers
use reduced compression bandaging
under 0.5 Severe arterial disease Urgent specialist referral Arterial ulcers
no compression bandaging used