Estimation of Central aortic pressure waveform by mathematical transformation of radial tonometry pressure: Validation of generalized transfer function

Chen Huan Chen, Erez Nevo, Barry Fetics, Peter H. Pak, Frank C.P. Yin, W. Lowell Maughan, David A. Kass

Research output: Contribution to journalArticlepeer-review

Abstract

Background: Central aortic pressures and waveform convey important information about cardiovascular status, but direct measurements are invasive. Peripheral pressures can be measured noninvasively, and although they often differ substantially from central pressures, they may be mathematically transformed to approximate the latter. We tested this approach, examining intersubject and intrasubject variability and the validity of using a single averaged transformation, which would enhance its applicability. Methods and Results: Invasive central aortic pressure by micromanometer and radial pressure by automated tonometry were measured in 20 patients at steady state anti during hemodynamic transients (Valsalva maneuver, abdominal compression, nitroglycerin, or vena caval obstruction). For each patient, transfer functions (TFs) between aortic and radial pressures were calculated by parametric model and results averaged to yield individual TFs. A generalized TF was the average of individual functions. TFs varied among patients, with coefficients of variation for peak amplitude and frequency at peak amplitude of 24.9% and 16.9%, respectively. Intrapatient TF variance with altered loading (>20% variation in peak amplitude) was observed in 28.5% of patients. Despite this, the generalized TF estimated central arterial pressures to ≤0.2±3.8 mm Hg error, arterial compliance to 6±7% accuracy, anti augmentation index to within -7% points (30±45% accuracy). Individual TFs were only marginally superior to the generalized TF for reconstructing central pressures. Conclusions: Central aortic pressures can be accurately estimated from radial tonometry with the use of a generalized TF. The reconstructed waveform can provide arterial compliance estimates but may underestimate the augmentation index because the latter requires greater fidelity reproduction of the wave contour.

Original languageEnglish (US)
Pages (from-to)1827-1836
Number of pages10
JournalCirculation
Volume95
Issue number7
DOIs
StatePublished - Apr 1 1997

Keywords

  • aorta
  • blood pressure
  • diagnosis

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Fingerprint

Dive into the research topics of 'Estimation of Central aortic pressure waveform by mathematical transformation of radial tonometry pressure: Validation of generalized transfer function'. Together they form a unique fingerprint.

Cite this