title: The Impact of Direct Cardiac Output Determination On Using A Widely Available Direct Continuous Oxygen Consumption Measuring Device On The Hemodynamic Assessment of Aortic Valve.
abstract: Accurate assessment of cardiac output (CO) is essential for the hemodynamic assessment of aortic valve area (AVA). Estimation of oxygen consumption (VO2) and Thermodilution (TD) is employed in many cardiac catheterization laboratories (CCL) given the historically cumbersome nature of direct continuous VO2 measurement, the "gold standard" for this technique. A portable facemask device simplifies the direct continuous measurement of VO2, allowing for relatively rapid and continuous assessment of CO and AVA.
  
  
  
  Seventeen consecutive patients undergoing right heart catheterization had simultaneous determination of CO by both direct continuous and assumed VO2 and TD. Assessments were only made when a plateau of VO2 had occurred. All measurements of direct continuous and assumed VO2, as well as, TD CO were obtained in triplicate.
  
  
  
  Direct continuous VO2 CO and assumed VO2 CO correlated poorly (R= 0.57; ICC =0.59). Direct continuous VO2 CO and TD CO also correlated poorly (R= 0.51; ICC=0.60). Similarly AVA derived from direct continuous VO2 correlated poorly with those of assumed VO2 (R= 0.68; ICC=0.55) and TD (R=0.66, ICC=0.60). Repeated direct continuous VO2 CO and AVA measurements were extremely correlated and reproducible [(R=0.93; ICC=0.96) and (R=0.99; ICC>0.99) respectively], suggesting that this was the most reliable measurement of CO.
  
  
  
  CO calculated from direct continuous VO2 measurement varies substantially from both assumed VO2 and TD based CO, which are widely used in most CCL. These differences may significantly impact the CO and AVA measurements. Furthermore, continuous, rather than average, measurement of VO2 appears to give highly reproducible results.
authors.affiliation: Division of Cardiology, University of Kansas School of Medicine, Kansas City, KS, USA.
authors.forename: Zaher
authors.initials: Z
authors.lastname: Fanari
authors.affiliation: Section of Cardiology, Carolina East Medical Center, New Bern, NC, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Grove
authors.affiliation: Division of Cardiology, Mount Sinai Heart, New York, NY, USA.
authors.forename: Anitha
authors.initials: A
authors.lastname: Rajamanickam
authors.affiliation: Section of Cardiology, Christiana Care Health System, Newark, DE, USA.
authors.forename: Sumaya
authors.initials: S
authors.lastname: Hammami
authors.affiliation: Section of Cardiology, Christiana Care Health System, Newark, DE, USA.
authors.forename: Cassie
authors.initials: C
authors.lastname: Walls
authors.affiliation: Value Institute, Christiana Care Health System, Newark, DE, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Kolm
authors.affiliation: Section of Cardiology, Christiana Care Health System, Newark, DE, USA.
authors.forename: Mitchell
authors.initials: M
authors.lastname: Saltzberg
authors.affiliation: Section of Cardiology, Christiana Care Health System, Newark, DE, USA; Value Institute, Christiana Care Health System, Newark, DE, USA.
authors.forename: William S
authors.initials: WS
authors.lastname: Weintraub
authors.affiliation: Section of Cardiology, Christiana Care Health System, Newark, DE, USA; Value Institute, Christiana Care Health System, Newark, DE, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Doorey
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000503:physiopathology*; D006328:Cardiac Catheterization / Q000295:instrumentation* / Q000379:methods; D002302:Cardiac Output / Q000502:physiology*; D005260:Female; D006334:Heart Function Tests / Q000295:instrumentation; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*
keywords: Aortic valve area; Assumed Oxygen Consumption; Cardiac Output; Direct continuous Oxygen Consumption; Thermodilution