Preliminary assessment of an automatic screening device for peripheral arterial disease using ankle-brachial and toe-brachial indices.

Background And Objectives: Ankle-brachial index (ABI) is currently recommended for the screening of peripheral arterial disease. However, this method becomes less reliable in the presence of calcified, incompressible arteries, as they result in an erroneously elevated ABI, and an additional measure termed the toe-brachial index (TBI) is recommended. The evaluation of ABI, and in particular TBI, typically requires significant technical skill and often involves referral to a vascular laboratory. This present situation reveals the need for a valid and reliable, automatic, noninvasive device that will provide both ABI and TBI at the level of the primary care physician. The aim of this study was to evaluate the accuracy and reliability of such a device, the Vasera VS-1500AT, in the assessment of toe, ankle, and brachial systolic blood pressures.

Materials And Methods: This study involved the assessment of 80 limbs from 40 normotensive and hypertensive individuals (17 men and 23 women) with a mean age of 45 ± 18 years.

Results: There was a statistically significant correlation (r=0.92) between toe systolic blood pressures obtained manually with photoplethysmography compared with those obtained through the automated device. The same significant correlation was also seen between the two with ankle (r=0.87) and brachial (r=0.88) systolic blood pressures.

Conclusion: These strong correlations demonstrate that further investigation of this device is warranted regarding its use as a screening tool for the assessment of peripheral arterial disease. The automation provided by this device could potentially eliminate variability in these measurements thereby allowing for screening and diagnosis to be done without referral to a vascular laboratory.