LAUSR

D espite a rollercoaster-like trend caused by a series of scientific confirmations and confutations related to its clinical usefulness, the interest upon the noninvasive estimation of central blood pressure (cBP) is still on the rise. There are many convincing reasons supporting the clinical application of cBP. Pressure waveform changes between the aorta and periphery have an important relationship with the structure and the function of large arteries and may therefore be considered a marker of vascular ageing, a parameter which is increasing in prominence in daily clinical practice [1]. Another reason is the possibility to use cBP to directly relate indexes of myocardial performance, such as stroke work, left ventricular contractile reserve and myocardial energetic efficiency, to aortic, not to brachial, pressure load [2,3]. Measurement of cBP from upper-arm cuff (brachial)based oscillometric devices, instead of classical tonometry methods, is more attractive for three further reasons. First, cuff devices are familiar in clinical practice, promoting the easy-use of cBP. Second, these devices are suitable for 24-h ambulatory BP monitoring [4]. Third, these devices measure the peripheral waveform and BP for waveform calibration at the same site. This final reason should not be underestimated. Indeed, for all devices that reconstruct the central arterialwaveform, calibrationof theperipheralwaveform is a fundamental step to obtain absolute values of cBP. The most common process of peripheral waveform calibration to generate the central waveform is based on identification of its two extremes (SBP and DBP), which then allows mean arterial pressure (MAP) to be found by integrating the area under the waveform curve. MAP, obtained by waveform integration, and DBP therefore can be applied to waveforms to calculate cSBP values following the rationale that, as opposite to SBP (and pulse