%0 Journal Article
%T Repeatability of Peripheral Artery Tonometry in Female Subjects
%A Andrew J. Degnan
%A Nandini Shah
%A David M. Carty
%A John R. Petrie
%A Christian Delles
%A Markus P. Schneider
%J ISRN Vascular Medicine
%D 2013
%R 10.1155/2013/383624
%X Background. Peripheral arterial tonometry (PAT) is a novel, non-invasive and operator-independent method for simultaneous assessment of endothelial function and arterial stiffness. We examined the repeatability of PAT in females and the influence of the estrous cycle. Methods. In 14 healthy female and five healthy male control subjects, PAT was performed on three separate occasions with 10 days between visits. Reactive hyperemia index (RHI), a measure of endothelial function, and peripheral augmentation index (AIx), a measure of arterial stiffness, were determined with the EndoPAT-2000 system. Intraclass correlation coefficient (ICC) was calculated as a measure of repeatability. Results. In both female and male groups, RHI and AIx did not differ between the three measurements (all n.s. by 1-way ANOVA). In females, reanalyzing the data after taking phase of estrous cycle into account had no effect on the results. Repeatability for RHI and AIx in females (ICC for RHI = 0.43, ICC for AIx = 0.78) was similar to that in male subjects (ICC for RHI = 0.42, ICC for AIx = 0.63). Conclusions. PAT measurements were not affected by the estrous cycle in females, and repeatability was comparable to that in males. This should facilitate inclusion of female subjects into vascular function studies using PAT. 1. Background Endothelial dysfunction is an important mechanism in the initiation and progression of atherosclerotic lesions. By using forearm plethysmography with intra-arterial administration of vasoactive agents, impaired endothelium-dependent vasodilation has been demonstrated in patients with a variety of conditions such as arterial hypertension [1, 2], hypercholesterolemia [3], and diabetes mellitus [4]. Of potential interest for clinical decision making, impaired endothelial function is an independent predictor of future cardiovascular (CV) events [5¨C7]. Ultrasound-based assessment of flow-mediated vasodilation (FMD) of the brachial artery is a noninvasive alternative method, also predicting future CV events [8, 9]. However, FMD testing requires substantial training. It has been recommended that at least 100 supervised training scans should be performed prior to scanning patients independently, and 100 scans per year are required to maintain competency [10]. Although the prognostic value of endothelial function testing has been recognized, guidelines do not currently recommend testing routinely, as current methods are invasive, laborious, and/or time consuming [11]. Peripheral arterial tonometry (PAT) is a novel method that promises to overcome some of these
%U http://www.hindawi.com/journals/isrn.vascular.medicine/2013/383624/