Reproducibility of derived central arterial waveforms in patients with chronic renal failure

Abstract

Arterial stiffness potently predicts mortality in dialysis patients. Pulse-wave analysis permits the non-invasive assessment of indices of arterial stiffness and the central pressure waveform by applanation tonometry. The aim of this study was to assess the reproducibility of pulse-wave analysis in patients with chronic renal failure. A total of 188 subjects (23 healthy controls, along with 71 pre-dialysis, 67 dialysis and 27 transplant patients) took part. Duplicate measurements were recorded of brachial blood pressure using the semi-automated Omron 705 device and of the radial artery pressure waveform using applanation tonometry. The central pressure aortic waveform was then obtained by application of a transfer function incorporated into the SphygmoCor software. Central aortic mean blood pressure (MBP), indices of arterial stiffness [augmentation index (AIx) and time to reflection (TR)] and the subendocardial viability ratio (SEVR) were analysed for intra-observer, inter-observer and long-term reproducibility using Bland-Altman plots. The mean (pS.D.) intra-observer difference was 0p4 % for AIx, 0p20 ms for TR, 0p3 mmHg for aortic MBP and 0p18 % for the SEVR. Inter-observer mean differences were 0p3 % for AIx, 1p7 ms for TR, 1p4 mmHg for aortic MBP and 1p9 % for the SEVR. For the long-term study, the mean differences were k1p9 % for AIx, k2p13 mmHg for aortic MBP, k2p12 ms for TR and 1p29 % for the SEVR. Pulse-wave analysis showed excellent reproducibility in all the studies, and is therefore suitable for use in all patients with chronic renal failure. Further prospective and interventional studies are now required to assess whether AIx and TR are important prognostic indices of cardiovascular events, and therefore relevant surrogate indices of arterial stiffness in this susceptible population.

Arterial Stiffness and Wave Reflections in Patients With Sickle Cell Disease

“…19,23 The reproducibility of derived AI has been previously validated. 23,24 In our hands (D.L. ), within-session coefficient of variation for derived AI measures using SphygmocoR is 6.8Ϯ7.3% (nϭ25) and is comparable to those of Wilkinson et al 23 and Savage et al 24 …”

A comparison between central blood pressure values obtained by the Gaon system and the SphygmoCor system

“…Different results could occur according to the measuring environment. 21 However, the reproducibility of the central cardiovascular parameters 22 estimated by the SphygmoCor system has already been confirmed, 3 and thus this explanation is also likely to be insufficient for explaining the poor correlation between the parameters estimated by the two systems.…”

Does immunosuppressant medication lower blood pressure and arterial stiffness in patients with chronic kidney disease? An observational study

“…The method has been shown to be reproducible in both healthy subjects and in patients with renal impairment. [22][23][24] Given the known effects of heart rate, the results for AIx were corrected to a heart rate of 75 beats per min (AIx 75 ). 25 …”

“…[22][23][24] In brief, a high-fidelity micromanometer (SPC-301; Millar Instruments, Houston, TX, USA) was used to flatten, but not occlude the radial artery using gentle pressure. Data were collected directly into a portable computer and, after 11 s of data capture, an averaged peripheral waveform, and a corresponding central waveform, was generated.…”