title: The effect of coenzyme Q10 in patients with congestive heart failure.
abstract: BACKGROUND
  Coenzyme Q10 is commonly used to treat congestive heart failure on the basis of data from several unblinded, subjective studies. Few randomized, blinded, controlled studies have evaluated objective measures of cardiac performance.
  
  
  OBJECTIVE
  To determine the effect of coenzyme Q10 on peak oxygen consumption, exercise duration, and ejection fraction.
  
  
  METHODS
  Randomized, double-blind, controlled trial.
  
  
  METHODS
  University and Veterans Affairs hospitals.
  
  
  METHODS
  55 patients who had congestive heart failure with New York Heart Association class III and IV symptoms, ejection fraction less than 40%, and peak oxygen consumption less than 17.0 mL/kg per minute (or <50% of predicted) during standard therapy were randomly assigned. Forty-six patients completed the study.
  
  
  METHODS
  Coenzyme Q10, 200 mg/d, or placebo.
  
  
  METHODS
  Left ventricular ejection fraction (measured by radionuclide ventriculography) and peak oxygen consumption and exercise duration (measured by a graded exercise evaluation using the Naughton protocol) with continuous metabolic monitoring.
  
  
  RESULTS
  Although the mean (+/-SD) serum concentration of coenzyme Q10 increased from 0.95+/-0.62 microg/mL to 2.2+/-1.2 microg/mL in patients who received active treatment, ejection fraction, peak oxygen consumption, and exercise duration remained unchanged in both the coenzyme Q10 and placebo groups.
  
  
  CONCLUSIONS
  Coenzyme Q10 does not affect ejection fraction, peak oxygen consumption, or exercise duration in patients with congestive heart failure receiving standard medical therapy.
authors.affiliation: University of Maryland School of Medicine and Veterans Affairs Medical Center, Baltimore 21201, USA.
authors.forename: M
authors.initials: M
authors.lastname: Khatta
authors.forename: B S
authors.initials: BS
authors.lastname: Alexander
authors.forename: C M
authors.initials: CM
authors.lastname: Krichten
authors.forename: M L
authors.initials: ML
authors.lastname: Fisher
authors.forename: R
authors.initials: R
authors.lastname: Freudenberger
authors.forename: S W
authors.initials: SW
authors.lastname: Robinson
authors.forename: S S
authors.initials: SS
authors.lastname: Gottlieb
mesh_terms: D000975:Antioxidants / Q000378:metabolism / Q000627:therapeutic use*; D003067:Coenzymes; D004311:Double-Blind Method; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010919:Placebos; D015635:Radionuclide Ventriculography; D013318:Stroke Volume; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use
chemical_list: D000975:Antioxidants; D003067:Coenzymes; D010919:Placebos; D014451:Ubiquinone; C024989:coenzyme Q10