title: Non-Invasive Determination of Cardiac Output in Pre-Capillary Pulmonary Hypertension.
abstract: BACKGROUND
  Cardiac output (CO) is a major diagnostic and prognostic factor in pre-capillary pulmonary hypertension (PH). Reference methods for CO determination, like thermodilution (TD), require invasive procedures and allow only steady-state measurements. The Modelflow (MF) method is an appealing technique for this purpose as it allows non-invasive and beat-by-beat determination of CO.
  
  
  METHODS
  We aimed to compare CO values obtained simultaneously from non-invasive pulse wave analysis by MF (COMF) and by TD (COTD) to determine its precision and accuracy in pre-capillary PH. The study was performed on 50 patients with pulmonary arterial hypertension (PAH) or chronic thrombo-embolic PH (CTEPH). CO was determined at rest in all patients (n = 50) and during nitric oxide vasoreactivity test, fluid challenge or exercise (n = 48).
  
  
  RESULTS
  Baseline COMF and COTD were 6.18 ± 1.95 and 5.46 ± 1.95 L·min-1, respectively. Accuracy and precision were 0.72 and 1.04 L·min-1, respectively. Limits of agreement (LoA) ranged from -1.32 to 2.76 L·min-1. Percentage error (PE) was ±35.7%. Overall sensitivity and specificity of COMF for directional change were 95.2% and 82.4%, (n = 48) and 93.3% and 100% for directional changes during exercise (n = 16), respectively. After application of a correction factor (1.17 ± 0.25), neither proportional nor fixed bias was found for subsequent CO determination (n = 48). Accuracy was -0.03 L·min-1 and precision 0.61 L·min-1. LoA ranged from -1.23 to 1.17 L·min-1 and PE was ±19.8%.
  
  
  CONCLUSIONS
  After correction against a reference method, MF is precise and accurate enough to determine absolute values and beat-by-beat relative changes of CO in pre-capillary PH.
authors.affiliation: Service de Pneumologie, Programme Hypertension Pulmonaire, Hôpitaux Universitaires de Genève, Genève, Switzerland.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lador
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Centre Chirurgical Marie-Lannelongue, Le Plessis-Robinson, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Hervé
authors.affiliation: Département des Neuroscience Fondamentales, Centre Médical Universitaire, Université de Genève, Genève, Switzerland.
authors.forename: Aurélien
authors.initials: A
authors.lastname: Bringard
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Sven
authors.initials: S
authors.lastname: Günther
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Garcia
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Savale
authors.affiliation: Département des Neuroscience Fondamentales, Centre Médical Universitaire, Université de Genève, Genève, Switzerland; Dipartimento di Scienze Cliniche e Sperimentali, Università di Brescia, Brescia, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Ferretti
authors.affiliation: Service de Pneumologie, Programme Hypertension Pulmonaire, Hôpitaux Universitaires de Genève, Genève, Switzerland.
authors.forename: Paola M
authors.initials: PM
authors.lastname: Soccal
authors.affiliation: Département de Physiologie, Université Paris-Sud, Faculté de Médecine-EA4533-APHP, Le Kremlin Bicêtre, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Chemla
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Humbert
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Gérald
authors.initials: G
authors.lastname: Simonneau
authors.affiliation: AP-HP, Centre de Référence de l'Hypertension Pulmonaire Sévère, Département Hospitalo-Universitaire (DHU) Thorax Innovation (TORINO), Service de Pneumologie, Hôpital de Bicêtre, Le Kremlin Bicêtre, France; Université Paris-Sud, Faculté de Médecine, Le Kremlin Bicêtre, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Sitbon
mesh_terms: D006328:Cardiac Catheterization / Q000379:methods; D002302:Cardiac Output / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D013815:Thermodilution