title: Correlation between CD34+ and exercise capacity, functional class, quality of life and norepinephrine in heart failure patients.
abstract: BACKGROUND
  A previous study associated CD34(+) levels with NYHA functional class in heart failure patients. The aim of this study was to correlate CD34(+) levels to exercise capacity, functional class, quality of life and norepinephrine in heart failure patients.
  
  
  METHODS
  Twenty three sedentary patients (52 +/- 7 years, 78% male) answered the Minnesota Living with Heart Failure Questionnaire and rested for 20 minutes before an investigator collect a blood sample. After this, patients performed a cardiopulmonary exercise test to determine the heart rate at anaerobic and ventilatory threshold and oxygen consumption at peak effort, at anaerobic and ventilatory threshold. One other blood sample was collected during the peak effort to investigate the norepinephrine and CD34(+) levels.
  
  
  RESULTS
  Rest percentage of CD34(+) did not show correlation with: left ventricle ejection fraction (r = 0.03, p = 0.888), peak VO(2) (r = 0.32, p = 0.13), VO(2) at anaerobic threshold (VO(2)AT) (r = 0.03, p = 0.86), VO(2) at ventilatory threshold (VO(2)VT) (r = 0.36, p = 0.08), NYHA functional class (r = -0.2, p = 0.35), quality of life (Minnesota) (r = -0.17, p = 0.42). CD34(+) did not show correlation, either, with: peak VO(2) (r = 0.38, p = 0.06), VO(2)AT (r = 0.09, p = 0.65), VO(2)VT (r = 0.43, p = 0.4), NYHA functional class (r = -0.13, p=0.54), quality of life (r = 0.00, p = 0.99).
  
  
  CONCLUSIONS
  CD34(+) levels did not correlate with exercise capacity, functional class, quality of life and norepinephrine. Percentage of CD34(+) levels did not increase during the cardiopulmonary exercise test in heart failure patients.
authors.affiliation: Laboratório de Insuficiencia Cardíaca e Transplante do Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da USP, Brazil. vitor.carvalho@usp.br
authors.forename: Vitor Oliveira
authors.initials: VO
authors.lastname: Carvalho
authors.forename: Milton Artur
authors.initials: MA
authors.lastname: Ruiz
authors.forename: Edimar Alcides
authors.initials: EA
authors.lastname: Bocchi
authors.forename: Vagner Oliveira
authors.initials: VO
authors.lastname: Carvalho
authors.forename: Guilherme Veiga
authors.initials: GV
authors.lastname: Guimarães
mesh_terms: D015308:Anaerobic Threshold; D018952:Antigens, CD34 / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D042783:Endothelial Cells / Q000276:immunology*; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000175:diagnosis / Q000276:immunology* / Q000503:physiopathology / Q000523:psychology / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood*; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D012123:Pulmonary Ventilation; D011788:Quality of Life; D020127:Recovery of Function; D012720:Severity of Illness Index; D013234:Stem Cells / Q000276:immunology*; D013318:Stroke Volume; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D016277:Ventricular Function, Left
chemical_list: D018952:Antigens, CD34; D015415:Biomarkers; D009638:Norepinephrine