The ankle/arm systolic blood pressure ratio as a screening test for arterial insufficiency in the lower limb.

Doppler-derived ankle/arm systolic blood pressure ratios were measured in 424 patients with ischaemic arterial disease of the lower limbs and in 52 controls. 90 of the patients were diabetic. The value of this simple test in screening for arterial insufficiency was evaluated retrospectively. The results were reproducible the coefficient of variation being about 10%. In most patients a test performed at rest was sufficient to detect arterial insufficiency. However, in some milder cases a stress test was needed to distinguish them from subjects without arterial insufficiency. In some patients with advanced diabetes mellitus false high pressure readings were recorded as a result of vessel wall stiffness. However, only one patient with mild diabetes had a false normal pressure ratio. In patients with distal gangrene diabetes mellitus caused erroneously high pressure ratios.