TY - JOUR
T1 - Measures of arterial stiffness and wave reflection are associated with walking distance in patients with peripheral arterial disease
AU - Brewer, La Princess C.
AU - Chai, High Seng
AU - Bailey, Kent R.
AU - Kullo, Iftikhar J.
N1 - Funding Information:
The authors would like to thank the study participants and acknowledge the staff of the Mayo Clinic Vascular Laboratory for their help with the study. This work was supported by NIH Grants K23-RR17720 and R01 HL75794 to I.J.K.; L.C. Brewer was supported by NIH Grant T35 HL07766-14.
PY - 2007/4
Y1 - 2007/4
N2 - We hypothesized that measures of arterial stiffness and wave reflection influence functional capacity of patients with peripheral arterial disease (PAD). Consecutive patients (n = 106, 69 ± 10 years, 66% men) referred for lower extremity arterial evaluation were studied. Radial artery pulse waveforms were obtained by applanation tonometry and an ascending aortic pressure waveform derived by a transfer function. Aortic augmentation index (AIx) is the difference between the first and second systolic peak of the ascending aortic pressure waveform indexed to the pulse pressure (PP) and Tr is the reflected wave arrival time. Ankle-brachial index (ABI) and walking distance were measured as per laboratory protocol after excluding patients with non-compressible vessels (ABI > 1.5) and severe PAD (ABI < 0.5). To account for right-censoring of walking distances in patients completing the 5 min walk (n = 56), we used survival analysis to identify variables associated with walking distance. Mean (±S.D.) values were: AIx, 31.2 ± 10.9%; Tr, 134 ± 18 ms; PP, 66.5 ± 17.1 mmHg; ABI, 0.87 ± 0.22; walking distance, 177 ± 75 m. In both multivariable accelerated failure time (AFT) and Cox proportional-hazards models, older age, female sex, greater body mass index, lower ABI, and a measure of arterial stiffness (higher AIx and PP, lower Tr) were associated with a lower walking distance. Higher AIx and lower Tr were associated with a lower walking distance even after adjustment for PP as well as in the subset of patients with PAD (ABI < 0.9 at rest or post-exercise, n = 82). In conclusion, measures of arterial stiffness and wave reflection are associated with walking distance in patients with PAD and may be a target of therapy in such patients.
AB - We hypothesized that measures of arterial stiffness and wave reflection influence functional capacity of patients with peripheral arterial disease (PAD). Consecutive patients (n = 106, 69 ± 10 years, 66% men) referred for lower extremity arterial evaluation were studied. Radial artery pulse waveforms were obtained by applanation tonometry and an ascending aortic pressure waveform derived by a transfer function. Aortic augmentation index (AIx) is the difference between the first and second systolic peak of the ascending aortic pressure waveform indexed to the pulse pressure (PP) and Tr is the reflected wave arrival time. Ankle-brachial index (ABI) and walking distance were measured as per laboratory protocol after excluding patients with non-compressible vessels (ABI > 1.5) and severe PAD (ABI < 0.5). To account for right-censoring of walking distances in patients completing the 5 min walk (n = 56), we used survival analysis to identify variables associated with walking distance. Mean (±S.D.) values were: AIx, 31.2 ± 10.9%; Tr, 134 ± 18 ms; PP, 66.5 ± 17.1 mmHg; ABI, 0.87 ± 0.22; walking distance, 177 ± 75 m. In both multivariable accelerated failure time (AFT) and Cox proportional-hazards models, older age, female sex, greater body mass index, lower ABI, and a measure of arterial stiffness (higher AIx and PP, lower Tr) were associated with a lower walking distance. Higher AIx and lower Tr were associated with a lower walking distance even after adjustment for PP as well as in the subset of patients with PAD (ABI < 0.9 at rest or post-exercise, n = 82). In conclusion, measures of arterial stiffness and wave reflection are associated with walking distance in patients with PAD and may be a target of therapy in such patients.
KW - Arterial stiffness
KW - Arteries
KW - Peripheral vascular disease
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U2 - 10.1016/j.atherosclerosis.2006.03.038
DO - 10.1016/j.atherosclerosis.2006.03.038
M3 - Article
C2 - 16730015
AN - SCOPUS:33947165304
SN - 0021-9150
VL - 191
SP - 384
EP - 390
JO - Atherosclerosis
JF - Atherosclerosis
IS - 2
ER -