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

Abstract

Central pulse pressure is correlated with carotid atherosclerosis and the incidence of cardiovascular events more significantly than brachial pulse pressure. Augmentation index (Aix) has been shown to be an independent predictor of cardiovascular morbidity and mortality. Pulse wave analysis using the Gaon system allows for the estimation of central blood pressure (CBP), corrected augmentation index (Aix@HR75), ejection duration (ED) and subendocardial viability ratio (SEVR), and is widely used in clinical research in Korea. However, the accuracy of this system is controversial. From February 2008 to March 2011, 99 patients were recruited for this study. Measurements were taken both by the Gaon system and the SphygmoCor system on the same day for all study participants. The estimated values of CBP, Aix@HR75, ED and SEVR for the two systems were compared using paired t-tests, simple correlation analyses and Bland-Altman plots. Systolic blood pressure (SBP) estimated by the two systems was significantly (Po0.001) correlated; the coefficient was 0.982. The two s.d. of the difference in SBP between these systems was quite small-o7 mm Hg. Aix@HR75, ED and SEVR as estimated by the two systems were also significantly correlated, although they, especially SEVR, showed much weaker correlations than were observed in SBP: coefficients for Aix@HR75, ED and SEVR were 0.727, 0.648 and 0.230, respectively. We assessed the CBP of Korean patients estimated by the two systems and observed that the correlations of Aix, ED and SEVR were weaker than that of CBP. Such variations may be due to the difference in measuring methods between the devices. As even a slight change in pulse waveforms may result in a large difference in estimations, parameters, including Aix@HR75, ED and SEVR, should be carefully interpreted by experienced clinicians.

Noninvasive evaluation of varying pulse pressures in vivo using brachial sphymomanometry, applanation tonometry, and Pulse Wave Ultrasound Manometry

“…This appears to contradict the notion that in older, hypertensive individuals, the reflected wave tends to arrive at the ascending aorta during early systole, resulting in an even greater increase in PP [37, 43]. However, the aforementioned studies have investigated central PP using either a generalized transfer function to derive the PP at the ascending aorta [44, 45], or cardiac catheterization at the aortic root [46]. Since this study represents the first non-invasive, direct measurements of PP in the abdominal aortas of pre-hypertensive and hypertensive subjects, it is possible that in some hypertensive cases (such as the one shown in Figure 3c), the arrival of the reflected wave at the abdominal aorta may not always cause pressure amplification.…”

A New Tonometric Device for Radial Augmentation Index and Subendocardial Viability Ratio: Potential Use in Health Screening

“…Although the SphygmoCor device can also measure both parameters with the use of a transfer function, the probe is handheld, which requires a more trained clinician for a good‐quality pulse waveform. In a recent study, the Goan was validated to derive aortic AIx and SEVR from a transformed aortic pressure . However, it has also been shown that the individual transfer function of different devices (SphygmoCor vs Goan) could have affected the absolute value of these indices.…”

“…In a recent study, the Goan was validated to derive aortic AIx and SEVR from a transformed aortic pressure. 6 However, it has also been shown that the individual transfer function of different devices (SphygmoCor vs Goan) could have affected the absolute value of these indices.…”

“…4,5 Since neither method is easy to operate, which is necessary for health screening, AIx is calculated from aortic pulse waveforms by means of a validated transfer function with the SphygmoCor device (AtCor Medical, Sydney, New South Wales, Australia). 6 Furthermore, AIx has been suggested to be obtained directly from the radial pulse waveform for simplifying the measurement procedure, 7 which could provide equivalent information as aortic AIx. 8,9 Several studies have shown that radial AIx was independently predictive of adverse cardiac events.…”

Efficacy of losartan and carvedilol on central hemodynamics in hypertensives: a prospective, randomized, open, blinded end point, multicenter study

“…The AIx was calculated from the right radial artery pulse waves using applanation tonometry (Gaon21A System; Hanbyul Meditech). 22,23 Previous studies 21,[23][24][25] showed that applanation tonometry provides a good indicator of ascending aortic pressure wave contour both in the control state and after acute therapeutic intervention, although the Gaon21A System lacks validation studies. Data that met the automatic quality controls specified by the integrated software were used to Comparison of losartan and carvedilol EJ Kim et al derive central aortic pressure waveforms by a generalized transfer function, from which aortic systolic BP and diastolic BP values were obtained.…”