Background: Recent studies emphasize the significance of vessel wall properties estimations of large arteries not only for research purposes, but even in clinical practice already. The newly launched OMRON device measures the radial augmentation index (AIx) automatically. The aim of this study was to compare intra-individually this device to the long-term established Sphygmocor device in patients with manifest coronary heart disease and in addition to do an intra-device comparison of the OMRON device.

Methods: The investigated sample was one hundred randomly selected patients with manifest coronary heart disease, a random sub-sample of the Czech EuroAspire III study series. The measurements of the radial augmentation index were done in virtually similar conditions, in 60% twice using the HEM9000AI (OMRON) device and once the Sphygmocor (ATCor Systems) device, the rest of the sample was measured once by both devices.

Results: The OMRON device measured in average a higher AIx than the Sphygmocor device and this intraindividual difference is highly statistically significant. The median intraindividual difference between both devices was 17.4%. Both estimations significantly corelate, however, the correlation coefficient is for this kind of comparison rather low (about 0.44). In the OMRON intradevice comparison the median intraindividual difference was 1.9%.

Conclusion: The OMRON and Sphygmocor device estimations were in coronary patients not biologically equivalent. In conclusion, the OMRON device showed a very low variability and is applicable for estimation of the radial augmentation index in clinical use. However, the result from one device does not seem to be transferable to the other.