title: Milrinone versus dobutamine in heart failure subjects treated chronically with carvedilol.
abstract: OBJECTIVE
  To compare the efficacy of milrinone and dobutamine in patients chronically treated with carvedilol.
  
  
  BACKGROUND
  Milrinone and dobutamine are used to manage decompensated heart failure, but their efficacy in patients on beta-blocker therapy was unknown.
  
  
  METHODS
  Twenty patients with decompensated heart failure were prospectively enrolled. Inotropic responses to milrinone (12.5, 25 or 50 microg/kg bolus infusions) or dobutamine (5, 10, 15 or 20 microg/kg/min infusions) were evaluated by right-heart catheterization.
  
  
  RESULTS
  Milrinone increased cardiac index (2.0-2.6 l/min/m2, P=0.0001) without significantly altering heart rate (70-75 bpm, P=0.19). Milrinone decreased mean pulmonary artery pressure (36-29 mm Hg, P=0.0001), pulmonary capillary wedge pressure (24-18 mm Hg, P=0.0001) and mean arterial blood pressure (78-75 mm Hg, P=0.0002). Left ventricular stroke volume index increased in the milrinone group (31-35 ml/beat/m2, P=0.0001). Dobutamine produced an increase in cardiac index (2.4-3.3 l/min/m2, P=0.0001) only at doses that are not typically used to treat heart failure (15-20 microg/kg/min). At these doses, dobutamine increased heart rate (68-82 bpm, P=0.008), mean systemic pressure (90-117 mm Hg, P=0.0001) and mean pulmonary artery pressure (21-30 mm Hg, P=0.001). Dobutamine did not alter left ventricular stroke volume index or pulmonary capillary wedge pressure.
  
  
  CONCLUSIONS
  Dobutamine and milrinone have different hemodynamic effects in patients treated chronically with carvedilol. These differences should be considered when selecting inotropic therapy for decompensated heart failure.
authors.affiliation: University of Colorado Health Sciences Center, Denver, Colorado, CO 80262, USA. brianlowes@uchsc.edu
authors.forename: B D
authors.initials: BD
authors.lastname: Lowes
authors.forename: T
authors.initials: T
authors.lastname: Tsvetkova
authors.forename: E J
authors.initials: EJ
authors.lastname: Eichhorn
authors.forename: E M
authors.initials: EM
authors.lastname: Gilbert
authors.forename: M R
authors.initials: MR
authors.lastname: Bristow
mesh_terms: D000318:Adrenergic beta-Agonists / Q000627:therapeutic use*; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D002227:Carbazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D002302:Cardiac Output / Q000187:drug effects; D000077261:Carvedilol; D004280:Dobutamine / Q000008:administration & dosage / Q000819:agonists*; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D006333:Heart Failure / Q000188:drug therapy*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D020105:Milrinone / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D011412:Propanolamines / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D011669:Pulmonary Wedge Pressure / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000187:drug effects
chemical_list: D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D010726:Phosphodiesterase Inhibitors; D011412:Propanolamines; D000077261:Carvedilol; D004280:Dobutamine; D020105:Milrinone