Central aortic blood pressure estimation in children and adolescents: results of the KidCoreBP study

Background: Central aortic SBP (cSBP) may have superior prognostic value compared with peripheral SBP (pSBP), but noninvasive cSBP measurement techniques have not been formally validated in children and adolescents. Method: This study assessed the accuracy of two automated devices and the radial tonometry/transfer function method (RT-TF) for estimating central pressures and pulse pressure amplification (PPA) in this population, with adherence to validation guidelines for central pressure devices. In 69 children/adolescents aged 3-18 years undergoing clinically indicated aortic catheterization, high fidelity ascending aortic cSBP was measured with a micromanometer-tipped wire and compared with values from SphygmoCor XCEL, Mobil-O-Graph (systolic/diastolic calibration, MoG-C1, or mean/diastolic calibration, MoG-C2) and RT-TF. Reference intra-arterial pSBP was derived from the tonometry pulse calibrated to central mean/diastolic pressures. Results: XCEL, MoG-C1 and MoG-C2 overestimated cSBP by 7.9±6.8mmHg (mean±SD), 5.7±10.3mmHg, and 19.1±14.9 mmHg, exceeding the validation cut-off (5±8mmHg). Brachial pSBP was also overestimated by XCEL (10.9±8.4mmHg) and Mobil-O-Graph (11.5±12.3mmHg). By contrast, central and brachial diastolic pressures were underestimated by the automated devices, albeit mostly within acceptable limits; pulse pressures were, therefore, substantially overestimated. Central-brachial PPA (4.5±4.4mmHg) was overestimated by XCEL (8.7±3.2mmHg) and MoG-C1 (11.1±6.4mmHg), but underestimated by MoG-C2 (-3.0±6.6mmHg). Given accurate pulse calibration, RT-TF achieved acceptable accuracy for cSBP (-0.2±4.6mmHg) and central-radial PPA (1.9±5.1mmHg). Conclusion: In conclusion, XCEL and Mobil-O-Graph overestimated pSBP and cSBP in children and adolescents. cSBP can be obtained via the same transfer function used in adults, but accurate pressure pulse calibration is critical. Video Abstracts: http://links.lww.com/HJH/B222.