title: Exercise capacity and mortality in patients with ischemic left ventricular dysfunction randomized to coronary artery bypass graft surgery or medical therapy: an analysis from the STICH trial (Surgical Treatment for Ischemic Heart Failure).
abstract: OBJECTIVE
  The objective of this study was to assess the prognostic significance of exercise capacity in patients with ischemic left ventricular (LV) dysfunction eligible for coronary artery bypass graft surgery (CABG).
  
  
  BACKGROUND
  Poor exercise capacity is associated with mortality, but it is not known how this influences the benefits and risks of CABG compared with medical therapy.
  
  
  METHODS
  In an exploratory analysis, physical activity was assessed by questionnaire and 6-min walk test in 1,212 patients before randomization to CABG (n = 610) or medical management (n = 602) in the STICH (Surgical Treatment for Ischemic Heart Failure) trial. Mortality (n = 462) was compared by treatment allocation during 56 months (interquartile range: 48 to 68 months) of follow-up for subjects able (n = 682) and unable (n = 530) to walk 300 m in 6 min and with less (Physical Ability Score [PAS] >55, n = 749) and more (PAS ≤55, n = 433) limitation by dyspnea or fatigue.
  
  
  RESULTS
  Compared with medical therapy, mortality was lower for patients randomized to CABG who walked ≥300 m (hazard ratio [HR]: 0.77; 95% confidence interval [CI]: 0.59 to 0.99; p = 0.038) and those with a PAS >55 (HR: 0.79; 95% CI: 0.62 to 1.01; p = 0.061). Patients unable to walk 300 m or with a PAS ≤55 had higher mortality during the first 60 days with CABG (HR: 3.24; 95% CI: 1.64 to 6.83; p = 0.002) and no significant benefit from CABG during total follow-up (HR: 0.95; 95% CI: 0.75 to 1.19; p = 0.626; interaction p = 0.167).
  
  
  CONCLUSIONS
  These observations suggest that patients with ischemic left ventricular dysfunction and poor exercise capacity have increased early risk and similar 5-year mortality with CABG compared with medical therapy, whereas those with better exercise capacity have improved survival with CABG. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595).
authors.affiliation: Green Lane Cardiovascular Service, Auckland City Hospital, and University of Auckland, Auckland, New Zealand. Electronic address: rstewart@adhb.govt.nz.
authors.forename: Ralph A H
authors.initials: RA
authors.lastname: Stewart
authors.affiliation: Medical University of Gdansk, Department of Rehabilitation, Gdansk, Poland.
authors.forename: Dominika
authors.initials: D
authors.lastname: Szalewska
authors.affiliation: Duke Clinical Research Institute, Clinical Trial Biostatistics, Durham, North Carolina.
authors.forename: Lilin
authors.initials: L
authors.lastname: She
authors.affiliation: Duke Clinical Research Institute, Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Kerry L
authors.initials: KL
authors.lastname: Lee
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Mark H
authors.initials: MH
authors.lastname: Drazner
authors.affiliation: National Institute of Cardiology, Warsaw, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Lubiszewska
authors.affiliation: Dedinje Cardiovascular Institute, Belgrade, Serbia.
authors.forename: Dragana
authors.initials: D
authors.lastname: Kosevic
authors.affiliation: Bangkok Heart Hospital, Bangkok Hospital Group, Bangkok, Thailand.
authors.forename: Permyos
authors.initials: P
authors.lastname: Ruengsakulrach
authors.affiliation: Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: José C
authors.initials: JC
authors.lastname: Nicolau
authors.affiliation: Hotel-Dieu du CHUM, Montreal, Canada.
authors.forename: Benoit
authors.initials: B
authors.lastname: Coutu
authors.affiliation: All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Shiv K
authors.initials: SK
authors.lastname: Choudhary
authors.affiliation: Duke Clinical Research Institute, Department of Medicine-Cardiology, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Mark
authors.affiliation: Castle Hill Hospital/Hull Royal Infirmary, Kingston-upon-Hull, United Kingdom.
authors.forename: John G F
authors.initials: JG
authors.lastname: Cleland
authors.affiliation: Albert Einstein College of Medicine, Montefiore Medical Center, New York, New York.
authors.forename: Ileana L
authors.initials: IL
authors.lastname: Piña
authors.affiliation: Duke Clinical Research Institute, Department of Medicine-Cardiology, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Velazquez
authors.affiliation: University of Waria and Mazury, Department of Cardiology and Cardiosurgery, Olsztyn, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Rynkiewicz
authors.affiliation: Green Lane Cardiovascular Service, Auckland City Hospital, and University of Auckland, Auckland, New Zealand.
authors.forename: Harvey
authors.initials: H
authors.lastname: White
mesh_terms: D001026:Coronary Artery Bypass / Q000401:mortality; D015444:Exercise / Q000502:physiology; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006333:Heart Failure / Q000188:drug therapy / Q000401:mortality / Q000601:surgery; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000401:mortality / Q000601:surgery* / Q000628:therapy; D012307:Risk Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy / Q000401:mortality / Q000601:surgery*
keywords: coronary disease; heart failure; surgery; trials