title: Cardiopulmonary exercise testing and survival after elective abdominal aortic aneurysm repair†.
abstract: BACKGROUND
  Cardiopulmonary exercise testing (CPET) is increasingly used in the preoperative assessment of patients undergoing major surgery. The objective of this study was to investigate whether CPET can identify patients at risk of reduced survival after abdominal aortic aneurysm (AAA) repair.
  
  
  METHODS
  Prospectively collected data from consecutive patients who underwent CPET before elective open or endovascular AAA repair  (EVAR) at two tertiary vascular centres between January 2007 and October 2012 were analysed. A symptom-limited maximal CPET was performed on each patient. Multivariable Cox proportional hazards regression modelling was used to identify risk factors associated with reduced survival.
  
  
  RESULTS
  The study included 506 patients with a mean age of 73.4 (range 44-90). The majority (82.6%) were men and most (64.6%) underwent EVAR. The in-hospital mortality was 2.6%. The median follow-up was 26 months. The 3-year survival for patients with zero or one sub-threshold CPET value ([Formula: see text] at AT<10.2 ml kg(-1) min(-1), peak [Formula: see text]<15 ml kg(-1) min(-1) or [Formula: see text] at AT>42) was 86.4% compared with 59.9% for patients with three sub-threshold CPET values. Risk factors independently associated with survival were female sex [hazard ratio (HR)=0.44, 95% confidence interval (CI) 0.22-0.85, P=0.015], diabetes (HR=1.95, 95% CI 1.04-3.69, P=0.039), preoperative statins (HR=0.58, 95% CI 0.38-0.90, P=0.016), haemoglobin g dl(-1) (HR=0.84, 95% CI 0.74-0.95, P=0.006), peak [Formula: see text]<15 ml kg(-1) min(-1) (HR=1.63, 95% CI 1.01-2.63, P=0.046), and [Formula: see text] at AT>42 (HR=1.68, 95% CI 1.00-2.80, P=0.049).
  
  
  CONCLUSIONS
  CPET variables are independent predictors of reduced survival after elective AAA repair and can identify a cohort of patients with reduced survival at 3 years post-procedure. CPET is a potentially useful adjunct for clinical decision-making in patients with AAA.
authors.affiliation: Academic Surgery Unit, Education and Research Centre and National Institute for Cardiovascular Outcomes Research, Institute of Cardiovascular Science, University College London, London, UK.
authors.forename: S W
authors.initials: SW
authors.lastname: Grant
authors.affiliation: National Institute for Cardiovascular Outcomes Research, Institute of Cardiovascular Science, University College London, London, UK Centre for Health Informatics, Manchester Academic Health Science Centre, University of Manchester, Oxford Road, Manchester, UK.
authors.forename: G L
authors.initials: GL
authors.lastname: Hickey
authors.affiliation: Department of Anaesthesia, University of Manchester, Manchester Academic Health Science Centre, University Hospital of South Manchester, Southmoor Road, Manchester M23 9LT, UK.
authors.forename: N A
authors.initials: NA
authors.lastname: Wisely
authors.affiliation: Academic Surgery Unit, Education and Research Centre and.
authors.forename: E D
authors.initials: ED
authors.lastname: Carlson
authors.affiliation: Department of Anaesthesia, University of Manchester, Manchester Academic Health Science Centre, University Hospital of South Manchester, Southmoor Road, Manchester M23 9LT, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Hartley
authors.affiliation: Manchester Royal Infirmary, Department of Anaesthesia, Central Manchester University Hospitals, Manchester Academic Health Science Centre, Manchester, UK.
authors.forename: A C
authors.initials: AC
authors.lastname: Pichel
authors.affiliation: Manchester Royal Infirmary, Department of Anaesthesia, Central Manchester University Hospitals, Manchester Academic Health Science Centre, Manchester, UK.
authors.forename: D
authors.initials: D
authors.lastname: Atkinson
authors.affiliation: Academic Surgery Unit, Education and Research Centre and cnmcc@manchester.ac.uk.
authors.forename: C N
authors.initials: CN
authors.lastname: McCollum
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D017558:Elective Surgical Procedures / Q000379:methods / Q000401:mortality* / Q000706:statistics & numerical data; D057510:Endovascular Procedures / Q000379:methods / Q000401:mortality / Q000706:statistics & numerical data; D005080:Exercise Test / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods* / Q000706:statistics & numerical data; D016016:Proportional Hazards Models; D011446:Prospective Studies; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D014656:Vascular Surgical Procedures / Q000379:methods / Q000401:mortality* / Q000706:statistics & numerical data
keywords: abdominal aortic aneurysm; cardiopulmonary exercise test; cardiovascular surgical procedure; endovascular procedures