Arterial Pulse Wave Analysis aides in quantifying blood flow and assessing the stiffness of the arteries particularly in diabetic patients.
The measurement is taken just above the ankle. It is a very valuable tool to document the improvement or deterioration of arterial diseases.
When compared with the blood supply to the arms, the legs should have more supply since they do more work and have a bigger muscle mass.
Hence in normal individuals, the legs have around 110% circulation with respect to the arms. In arterial disease,
it is important to know how much is the reduction in flow and quantification can only be achieved by this test (and not Colour Doppler or any form of angiography).
The reading is called Ankle-Brachial Index (ABI) and is expressed as a ratio.
Normal limbs show an ABI ratio of 0.9 to 1.15, mild disease 0.6 to 0.8, moderate disease 0.45-0.6 and severe is less than 0.45 where wounds do not heal.
It is a useful test to monitor progression of arterial disease or efficacy of a revascularization procedure like angioplasty or bypass surgery.
In early cases the artery gets stiff before it gets narrow and the stiffness of the artery predicts presence of arterial disease and can be monitored with serial testing.
This is a useful test to monitor the arterial health in diabetics where the arteries start to harden at an early stage.