Variability of Peripheral Arterial Tonometry in the Measurement of Endothelial Function in Healthy Men

Abstract

Measurement of endothelial function using peripheral arterial tonometry (PAT) has been reported to be significantly correlated with coronary blood flow. Repetitive PAT measurements were performed in 22 healthy male subjects at test intervals of 1 hour (5 times within a day) and 0.5 hours (7 times within a day) to evaluate the variability of the reactive hyperemia index (RHI). A total of 10 subjects underwent additional repetitive PAT at 2 hour intervals (7 times within a day) for 3 consecutive days to evaluate the diurnal effects and day-to-day reproducibility. The RHI from each test was computed automatically based on a 15 minute recording of pulse wave amplitude changes of the fingers in response to reactive hyperemia induced by a 5 minute occlusion of the brachial artery. Intrasubject variability of RHI at different test intervals, defined as the coefficient of variation (CV) was 15.3% ± 5.3%, 16.1% ± 7.8%, and 22.6% ± 3.9% for the tests at 0.5 hour, 1 hour, and 2 hour intervals, respectively. Reactive hyperemia indices measured at the same time points on each of the 3 days were not statistically significant. The interday reproducibility, presented as intraclass correlation coefficients (ICC) ranged from −0.07 to 0.47. We conclude that repetitive PAT measurements have no carryover effect on RHI at 1 hour, and 2 hour intervals, and the RHI measured at 0.5 hour intervals is associated with a trend of increase. The interday reproducibility is relatively low and the intrasubject variability of RHI is similar to those observed in studies of flow-mediated dilation using brachial artery ultrasound scanning.

Effect of angiotensin receptor blockade on insulin sensitivity and endothelial function in abdominally obese hypertensive patients with impaired fasting glucose

“…At the baseline visit, the RH-PVA was 2.0, a result similar to what has been observed previously in healthy populations [20]. Baseline endothelial function was not different between the losartan- and placebo-treated subjects (Table 3).…”

“…In contrast, Koh et al [42] found that each of losartan, candesartan and irbesartan improved FMD (flow-mediated dilation) of the brachial artery compared with placebo in patients with mild-to-moderate essential hypertension. We did not detect an effect of ARB therapy on endothelial function measured by RH-PVA; however, our subjects’ RH-PVA response prior to intervention was similar to that reported previously in healthy subjects [9,20,43]. Although the present study did not have an internal control group of healthy individuals, these historical data suggest that our selection criteria did not effectively identify a group of subjects with endothelial dysfunction.…”

“…Secondly, our sample size may have been insufficient to detect changes in many of the examined biomarkers. Thirdly, both Bonetti et al [43] and Liu et al [20] found low interday reproducibility of the RH-PVA measurements. These reports suggest that our power calculation, based upon the repeatability of the brachial artery ultrasound technique, may have overestimated the power of our sample size.…”

Radial pulse transit time is an index of arterial stiffness

“…However, though a significant association was found between radial PTT and age, the information from radial PTT could not be expected to be identical to PWV, for the shape of the radial pulse was influenced by various factors. [28][29][30] In summary, PTT obtained directly from radial arterial waveforms was significantly associated with age in healthy adult with a wide age range. The effect of HR changes on radial PTT was insignificant until it was up to 80 b.p.m.…”

National Trends in Beverage Consumption in Children from Birth to 5 Years: Analysis of NHANES Across Three Decades

“…Research confirmed the effect of diurnal variation [123] and the effect of dietary components such as omega-3 fatty acids [27], polyphenol rich olive oil [124], chocolate [125], and tea [126]. Furthermore, measurements were influenced by drugs [81] and mental stress [127].…”