title: Central aortic blood pressure from ultrasound wall-tracking of the carotid artery in children: comparison with invasive measurements and radial tonometry.
abstract: Differences between central aortic root (c) and peripheral (p) systolic blood pressure (SBP) may be particularly marked in children, but noninvasive methods for assessing cSBP in children have not been validated. We compared estimates of cSBP obtained from radiofrequency ultrasound wall tracking of the carotid artery (ART.LAB system) with that measured directly by a catheter in the aortic root at the time of arterial cannulation. Carotid waveforms were calibrated from invasive measurements of mean and diastolic pressures. In 9 children aged 10.5 ± 5.0 years (mean ± SD), cSBP obtained from carotid wall tracking was highly correlated with invasive measures of cSBP (r=0.99) with mean (± SD) difference 3.9 ± 2.5 mm Hg. Second, we compared values of cSBP obtained from the carotid with those obtained using noninvasive applanation tonometry at the radial artery and a radial-to-aortic transfer function (SphygmoCor). Both carotid and radial tonometric measurements were calibrated from the same peripheral mean and diastolic measurements of blood pressure obtained by sphygmomanometry. In 84 children aged 13.2 ± 3.2 years, there was excellent agreement between the 2 methods (r=0.95; P<0.001) with mean difference 0.71 ± 3.7 mm Hg (95% confidence interval =-1.53 to 1.01). This invasive validation study confirms that cSBP as estimated by carotid wall tracking provides an acceptable measurement of true cSBP when calibration is from true mean and diastolic pressures. Close agreement of cSBP obtained by carotid wall tracking and radial tonometry suggests that these provide similar results when calibrated from the same peripheral blood pressure measurements.
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Laura
authors.initials: L
authors.lastname: Milne
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Louise
authors.initials: L
authors.lastname: Keehn
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Antoine
authors.initials: A
authors.lastname: Guilcher
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: John F
authors.initials: JF
authors.lastname: Reidy
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Narayan
authors.initials: N
authors.lastname: Karunanithy
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Eric
authors.initials: E
authors.lastname: Rosenthal
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Shakeel
authors.initials: S
authors.lastname: Qureshi
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Phil J
authors.initials: PJ
authors.lastname: Chowienczyk
authors.affiliation: From the Department of Clinical Pharmacology, King's College London, British Heart Foundation Centre, United Kingdom (L.M., L.K., A.G., P.J.C., M.D.S.); and Departments of Interventional Radiology (J.F.R., N.K.), Paediatric Cardiology (E.R., S.Q.), and Paediatric Nephrology (M.D.S.), Evelina London Children's Hospital, Guys and St Thomas' NHS Foundation Trust, London, United Kingdom. manish.sinha@nhs.net.
authors.forename: Manish D
authors.initials: MD
authors.lastname: Sinha
mesh_terms: D000293:Adolescent; D062186:Arterial Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D017534:Radial Artery; D015203:Reproducibility of Results; D014463:Ultrasonography
keywords: applanation tonometry; central blood pressure; hypertension; pediatrics; renal disease