Medicine & Science in Sports & Exercise:
G-32 Free Communication/Poster - Chronic Disease: JUNE 4, 2011 7:30 AM - 11:00 AM: ROOM: Hall B
1University of Texas, Austin, TX. 2Technology for Medicine, San Antonio, TX.
(No relationships reported)
Ankle-brachial index (ABI) is currently recommended for the screening of peripheral arterial disease (PAD). This method becomes less reliable in the presence of calcified incompressible arteries, such as those found in diabetics, and an additional measure termed the toe-brachial index (TBI) is often recommended. However, current methodologies to assess ABI and TBI require significant technical skills and often require referral to a vascular laboratory. This current situation reveals the need for a valid and reliable, automatic, noninvasive device that requires minimal technical skill to operate.
PURPOSE: To evaluate the accuracy of such a device, the Vasera VS-1500AT, in the assessment of toe, ankle, and brachial systolic blood pressures to be used for the calculation of ABI and TBI.
METHODS: This study involved the assessment of 80 limbs from 40 normotensive and hypertensive individuals (17 male/23 female) with a mean age of 45±18 years. Manual toe systolic blood pressures were assessed using photoplethysmography, and manual ankle and brachial systolic blood pressures were assessed using a Doppler flowmeter.
RESULTS: There was a statistically significant correlation (r=0.92) between toe systolic blood pressures obtained manually with photoplethysmography compared with those obtained via the automated device. The results of the Bland-Altman plot showed a mean difference of 8.3±11.8 mmHg. The similarly strong correlations were observed between the automatic and manual methods in ankle (r=0.87) and brachial (r=0.88) systolic blood pressures. They were consistent with the Bland-Altman plot showing mean differences of -2.1±7.0 and 4.5±8.6 mmHg.
CONCLUSION: There were strong correlations between automatically-obtained and manually-measured brachial, ankle, and toe systolic blood pressures. These results suggest that the automatic noninvasive device has good potential as a screening device for peripheral artery disease, one that is specifically targeted for diabetics.