The Evaluation of Exercise Performance in Patients with Peripheral Vascular Disease

Exercise performance in patients with peripheral vascular disease (PVD) has traditionally been evaluated by subjective endpoints during submaximal exercise testing. To date, standardized testing protocols to evaluate maximal exercise performance, employing objective endpoints, have not been developed for these patients. This study was designed to: 1) develop an exercise testing protocol that would reproducibly define the maximal exercise performance of patients with PVD; 2) determine the effect of walking speed on maximal performance; and 3) evalute the utility of cloudication pain as an endpoint during exercise. Twenty patients with PVD exercised on a treadmill with a progressive increase in grade to maximal claudication pain. Tests were conducted on multiple occasions comparing walking speeds of 2 mph and 3 mph, with comparable 1-MET increases in intensity every 3 minutes. At maximal exercise, measurements of exercise duration, oxygen consumption, heart rate, and blood pressure were similar between the two protocols, and treadmill speed did not affect the reproducibility of these variables. Maximal performance was defined equally by both protocols. In contrast, the perception of claudication pain during exercise was more reproducibly determined at 3 mph than at 2 mph. Testing patients at the faster walking speed may be preferable if the primary endpoint is to evaluate the severity of claudication pain during exercise.