What change in ankle pressure is typically monitored during treadmill tests for claudication?

During treadmill tests for claudication, a rapid decrease in ankle pressure is typically monitored as patients exercise. This occurs due to reduced blood flow to the legs, often caused by peripheral artery disease (PAD), which is characterized by narrowing or blockage of the arteries. As the muscles require more oxygen during physical activity, an inadequate supply due to the underlying vascular condition leads to a drop in ankle pressure.

The significance of monitoring this decrease is to assess the severity of claudication and the patient's ability to tolerate exercise, which can help in determining the appropriate treatment plan. Identifying this rapid decrease provides insight into how the upper limits of normal perfusion pressure are challenged during exertion, revealing the presence and extent of vascular disease.