title: Is Noninvasive Brachial Systolic Blood Pressure an Accurate Estimate of Central Aortic Systolic Blood Pressure?
abstract: Noninvasive brachial systolic blood pressure (nSBP-B) usually approaches invasive central systolic blood pressure (iSBP-C) with a high correlation. Whether nSBP-B is an accurate estimate of iSBP-C remained to be investigated. Thus, this study aimed to compare the errors of nSBP-B and noninvasive central systolic blood pressure (nSBP-C) with different techniques in estimating iSBP-C.
  
  
  
  Simultaneous invasive high-fidelity central aortic pressure waveforms and the noninvasive left brachial pulse volume recording (PVR) waveform were recorded in a Generation group ( N = 40) and a Validation group ( N = 100). The accuracy of the noninvasive estimates of iSBP-C obtained from analysis of the calibrated PVR waveform using the generalized transfer function (GTF), pulse waveform analysis (PWA), and N-point moving average (NPMA) methods was examined in the Validation group by calculating the mean absolute error (MAE).
  
  
  
  In Generation group, the MAE was 4.6±4.1mm Hg between nSBP-B and invasive brachial SBP, and 6.8±5.5mm Hg between nSBP-B and iSBP-C. In comparison, the MAE of between iSBP-C and nSBP-C with PWA, NPMA, and GTF were 5.5±4.5, 5.8±4.9, and 5.9±5.0mm Hg, respectively. In Validation group, the MAE of nSBP-B (6.9±4.6mm Hg) for estimating iSBP-C was significantly greater than that of PWA (5.0±3.4mm Hg) and NPMA (6.1±4.4mm Hg), and GTF (6.1±4.9mm Hg). The percentage of absolute band error ≤5mm Hg was 62% for nSBP-B, 69% for GTF, 83% for PWA, and 69% for NPMA.
  
  
  
  The accuracy of nSBP-B was inferior to the n SBP-C measures in estimating iSBP-C.
authors.affiliation: Molecular Imaging Center, National Taiwan University , Taipei , Taiwan.
authors.forename: Yuan-Ta
authors.initials: YT
authors.lastname: Shih
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Cheng
authors.forename: Shih-Hsien
authors.initials: SH
authors.lastname: Sung
authors.affiliation: Institute of Population Health Sciences, National Health Research Institutes , Miaoli , Taiwan.
authors.forename: Shao-Yuan
authors.initials: SY
authors.lastname: Chuang
authors.affiliation: Department of Biomedical Engineering, Chung Yuan Christian University , Chung-Li , Taiwan.
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Hu
authors.forename: Chen-Huan
authors.initials: CH
authors.lastname: Chen
mesh_terms: D001011:Aorta; D062186:Arterial Pressure; D001794:Blood Pressure; D001795:Blood Pressure Determination; D006801:Humans; D015203:Reproducibility of Results