title: Validation of the beat to beat measurement of blood velocity in the human ascending aorta by a new high temporal resolution Doppler ultrasound spectral analyser.
abstract: OBJECTIVE
  To develop and validate a high temporal resolution spectral analysis system for Doppler measurements of blood velocity in the ascending aorta.
  
  
  METHODS
  An observational laboratory and clinical study comparing Doppler velocity-based measurements with fluid collection, electromagnetic flow catheters and probes, and thermodilution.
  
  
  METHODS
  Tertiary referral cardiology unit and cardiac catheter laboratory.
  
  
  METHODS
  Patients undergoing routine cardiac catheterisation for ischaemic heart disease, cardiac failure, and primary pulmonary hypertension.
  
  
  RESULTS
  There was good agreement between Doppler-derived and electromagnetic cuff or catheter measurements of velocity in an experimental flow rig (SD of differences 4.75% for velocity integral) and in the patients (SD of differences 4% for velocity integral). There was also reasonably good agreement between simultaneous Doppler-derived and thermodilution-estimated cardiac output measurements in patients undergoing cardiac catheterisation (SD of differences 12.6%).
  
  
  CONCLUSIONS
  This new method of high temporal resolution spectral analysis improves the resolution of rapidly changing blood velocities and may improve the ability to describe blood velocity patterns in the ascending aorta.
authors.affiliation: Department of Cardiovascular Medicine, John Radcliffe Hospital, Oxford.
authors.forename: A J
authors.initials: AJ
authors.lastname: Coats
authors.forename: C
authors.initials: C
authors.lastname: Murphy
authors.forename: J
authors.initials: J
authors.lastname: Conway
authors.forename: P
authors.initials: P
authors.lastname: Sleight
mesh_terms: D000293:Adolescent; D000368:Aged; D001011:Aorta / Q000502:physiology; D001783:Blood Flow Velocity; D006328:Cardiac Catheterization; D002302:Cardiac Output / Q000502:physiology; D015150:Echocardiography, Doppler / Q000295:instrumentation*; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013057:Spectrum Analysis / Q000295:instrumentation*; D013815:Thermodilution