Usefulness of stress-loading test for ankle brachial index using an originally developed exercise device to detect...

In the detection of peripheral arterial disease (PAD), the post-exercise ankle brachial index (ABI) using a treadmill is useful although time consuming. We developed a stress-loading device that induces fatigue in the calf muscles while remaining in the supine position, which is designed to reduce delay between completion of the exercise and measurement and to reduce the potential for cardiac and cerebrovascular accident in at-risk persons.

Using our original device, we measured post-stress-loading ABI in 536 patients (1,072 legs) with lower extremity symptoms such as intermittent claudication. ABI was measured at rest and after stress loading by VaSera.

The sensitivity and specificity of resting ABI using a cutoff of 0.9 was 74.8% and 99.4%, respectively, and of post-stress-loading ABI was 85.0% and 99.6%, respectively. The absolute and percent decrease of ABI after stress loading was 0.09+/-0.10 and 13.6+/-13.9%, respectively, in the PAD group and 0.04+/-0.05 and 3.2+/-4.0%, respectively, in the non-PAD group, a statistically significant difference (P<0.01).

Our originally developed stress-loading device for measurement of ABI under load simplifies the test procedures and increases the testing precision to a level higher than that of resting ABI and to that comparable to the conventional treadmill method.