Response to Validation of Devices and Methods for Noninvasive Estimation of Central Aortic Blood Pressure in Children

We would like to congratulate Milne et al,1 because they conducted this study, which covers a great gap about the validity and feasibility of devices for noninvasive estimation of central blood pressure (c-BP) in children. This will be a reference article and thus it is critical to clarify a few issues. Both ART.LAB and SphygmoCor apparatuses are used for the noninvasive estimation of c-BP. In clinical practice, the pulse waves recorded by these devices are calibrated using BP values noninvasively measured at the brachial artery. Thus, a great emphasis should be given on the fact that in this study the recorded pulses by ART.LAB were validated by mean arterial pressure and diastolic BP values which were measured by invasive intra-arterial BP recordings. Because the errors of noninvasive brachial BP measurement (ie, by cuff sphygmomanometers) are expected to be transferred to the c-BP estimation, it would be enlightening if the authors provide (if possible) the respective error in c-BP estimation by the ART.LAB system when it is calibrated using mean and diastolic brachial BP values measured noninvasively, similar to the procedure followed …