title: A new approach to determine parallel conductance for left ventricular volume measurements.
abstract: OBJECTIVE
  To determine absolute ventricular volume with the conductance catheter technique, the electrical conductance of tissues and fluids (parallel conductance) around the ventricle should be determined precisely.
  
  
  METHODS
  A new objective method to estimate parallel conductance based on analysis of the dilution curve of hypertonic saline was investigated. The parallel conductances obtained with the new method (G(a)(p)) were compared to those obtained with the conventional method (G(l)(p)). The study was performed in the left ventricle of 12 patients.
  
  
  RESULTS
  G(a)(p) was not significantly different from G(l)(p). For the G(l)(p) method the average percentage difference between duplicate values, both taken as absolute values, was 15.06% and for the G(a)(p) method it was 4. 01%. Thus the reproducibility of the method is a factor four better than that of the method. This difference appeared to be significant.
  
  
  CONCLUSIONS
  We conclude that a smaller number of injections will be required to obtain the same precision using our method.
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands. l.kornet@fys.unimaas.nl
authors.forename: L
authors.initials: L
authors.lastname: Kornet
authors.forename: J J
authors.initials: JJ
authors.lastname: Schreuder
authors.forename: E T
authors.initials: ET
authors.lastname: van der Velde
authors.forename: J
authors.initials: J
authors.lastname: Baan
authors.forename: J R
authors.initials: JR
authors.lastname: Jansen
mesh_terms: D006328:Cardiac Catheterization; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology*; D004553:Electric Conductivity; D006339:Heart Rate; D006352:Heart Ventricles / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D015203:Reproducibility of Results; D012462:Saline Solution, Hypertonic; D013318:Stroke Volume; D013815:Thermodilution
chemical_list: D012462:Saline Solution, Hypertonic