ABSTRACT
OBJECTIVE: Impaired functional capacity predicts morbidity and increased mortality in patients with PAD. We hypothesized that brachial-ankle pulse wave velocity (baPWV), a measure of arterial stiffness, is associated with functional capacity in patients undergoing noninvasive evaluation for peripheral arterial disease (PAD). METHODS: We studied 114 patients (age 68+/-10 years) referred to Mayo Clinic's noninvasive vascular laboratory. Functional capacity was estimated in terms of distance walked in 5 min on a treadmill at a speed of 1.0-2.0 mph. Ankle-brachial index (ABI) was obtained with Doppler method before and 1 min after exercise. baPWV was estimated noninvasively using an oscillometric device. The association of baPWV with walking distance was assessed using accelerated failure time and Cox proportional-hazards models. RESULTS: The mean baPWV was higher in patients who were unable to complete the walk test compared to those who successfully completed the test (P=0.008). Higher baPWV was associated with a lower walking distance after adjustment for heart rate, mean arterial pressure, and cardiovascular risk factors (P=0.017) and after additional adjustment for pulse pressure (P=0.034) and ABI (P=0.030). Higher baPWV was associated with failure to complete the treadmill walk test, after adjustment for heart rate, mean arterial pressure, and cardiovascular risk factors (P=0.025) and after additional adjustment for pulse pressure (P=0.041) and ABI (P=0.039). CONCLUSION: Increased baPWV, a measure of arterial stiffness, is associated with impaired functional capacity in patients undergoing evaluation for PAD.
