Aortic pulse wave velocity and reflecting distance estimation from peripheral waveforms in humans: detection of age- and exercise training-related differences

Abstract

We hypothesized that demographic/anthropometric parameters can be used to estimate effective reflecting distance (EfRD), required to derive aortic pulse wave velocity (APWV), a prognostic marker of cardiovascular risk, from peripheral waveforms and that such estimates can discriminate differences in APWV and EfRD with aging and habitual endurance exercise in healthy adults. Ascending aortic pressure waveforms were derived from peripheral waveforms (brachial artery pressure, n = 25; and finger volume pulse, n = 15) via a transfer function and then used to determine the time delay between forward- and backward-traveling waves (Δtf-b). True EfRDs were computed as directly measured carotid-femoral pulse wave velocity (CFPWV) × 1/2Δtf-b and then used in regression analysis to establish an equation for EfRD based on demographic/anthropometric data (EfRD = 0.173·age + 0.661·BMI + 34.548 cm, where BMI is body mass index). We found good agreement between true and estimated APWV (Pearson's R² = 0.43; intraclass correlation = 0.64; both P < 0.05) and EfRD (R² = 0.24; intraclass correlation = 0.40; both P < 0.05). In young sedentary (22 ± 2 years, n = 6), older sedentary (62 ± 1 years, n = 24), and older endurance-trained (61 ± 2 years, n = 14) subjects, EfRD (from demographic/anthropometric parameters), APWV, and 1/2Δtf-b (from brachial artery pressure waveforms) were 52.0 ± 0.5, 61.8 ± 0.4, and 60.6 ± 0.5 cm; 6.4 ± 0.3, 9.6 ± 0.2, and 8.1 ± 0.2 m/s; and 82 ± 3, 65 ± 1 and 76 ± 2 ms (all P < 0.05), respectively. Our results demonstrate that APWV derived from peripheral waveforms using age and BMI to estimate EfRD correlates with CFPWV in healthy adults. This method can reliably detect the distal shift of the reflecting site with age and the increase in APWV with sedentary aging that is attenuated with habitual endurance exercise.

The effect of lifelong exercise frequency on arterial stiffness

“…The Modelflow Aortic Age in central arterial stiffness with exercise training measured in this and other studies (Vaitkevicius et al 1993;Tanaka et al 1998;Tanaka et al 2000;Gates et al 2003;Pierce et al 2013) are not secondary to central blood pressure changes.…”

Physical activity modulates arterial stiffness in children with congenital heart disease: A CHAMPS cohort study

“…Prior work has shown that physical activity levels may be fundamental in the progression of arterial stiffness, as even in the absence of CHD, both children and adults have increased arterial stiffness when more sedentary. Consistent with our findings of a negative relationship between physical activity and arterial stiffness in children with CHD, others have reported in healthy prepubescent children that arterial stiffness was negatively correlated with cardiorespiratory fitness and step count .…”

Baseline aortic pulse wave velocity is associated with central and peripheral pressor responses during the cold pressor test in healthy subjects

“…; Pierce et al. , ) and can be reduced with acute exercise‐training even in aged, sedentary and diseased individuals (Tabara et al. ; Madden et al.…”

“…We chose to examine the relationship between baseline aortic pulse wave velocity and the pressor responses during CPT, rather than its increase during the CPT, because baseline aortic pulse wave velocity is an independent predictor of cardiovascular events (Sutton-Tyrrell et al 2005;Mattace-Raso et al 2006;Willum-Hansen et al 2006;Mitchell et al 2010). Furthermore, while aortic pulse wave velocity increases through age (Mitchell et al 2004;McEniery et al 2005) it is lower in individuals with a history of lifelong habitual exercise training relative to sedentary counterparts (Vaitkevicius et al 1993;Tanaka et al 1998;Gates et al 2003;Pierce et al 2013Pierce et al , 2016 and can be reduced with acute exercise-training even in aged, sedentary and diseased individuals (Tabara et al 2007;Madden et al 2009;Corrick et al 2013;Tanaka et al 2013;Vogel et al 2013;Donley et al 2014). Therefore, while chronological aging and increasing arterial stiffness generally share a close relationship there is likely between subject variations in this relationship.…”

“…These similarities suggest that alterations in central and peripheral pulse pressures during increased sympathetic activity may be comparable between a cold pressor test and skin surface cooling although further studies are required to clarify this. Furthermore, physical fitness and habitual activity influence vascular health (Vaitkevicius et al 1993;Tanaka et al 1998Tanaka et al , 2013Gates et al 2003;Tabara et al 2007;Madden et al 2009;Corrick et al 2013;Pierce et al 2013Pierce et al , 2016Vogel et al 2013;Donley et al 2014) while baroreflex sensitivity also changes with age and arterial stiffening (Monahan et al 2001a,b;Pierce et al 2016). We did not measure these and differences in these variables within our subject pool may have influenced the pressor responses to the cold pressor test.…”