title: High-intensity interval exercise training before abdominal aortic aneurysm repair (HIT-AAA): protocol for a randomised controlled feasibility trial.
abstract: BACKGROUND
  In patients with large abdominal aortic aneurysm (AAA), open surgical or endovascular aneurysm repair procedures are often used to minimise the risk of aneurysm-related rupture and death; however, aneurysm repair itself carries a high risk. Low cardiopulmonary fitness is associated with an increased risk of early post-operative complications and death following elective AAA repair. Therefore, fitness should be enhanced before aneurysm repair. High-intensity interval exercise training (HIT) is a potent, time-efficient strategy for enhancing cardiopulmonary fitness. Here, we describe a feasibility study for a definitive trial of a pre-operative HIT intervention to improve post-operative outcomes in patients undergoing elective AAA repair.
  
  
  METHODS
  A minimum of 50 patients awaiting elective repair of a 5.5-7.0 cm infrarenal AAA will be allocated by minimisation to HIT or usual care control in a 1:1 ratio. The patients allocated to HIT will complete three hospital-based exercise sessions per week, for 4 weeks. Each session will include 2 or 4 min of high-intensity stationary cycling followed by the same duration of easy cycling or passive recovery, repeated until a total of 16 min of high-intensity exercise is accumulated. Outcomes to be assessed before randomisation and 24-48 h before aneurysm repair include cardiopulmonary fitness, maximum AAA diameter and health-related quality of life. In the post-operative period, we will record destination (ward or critical care unit), organ-specific morbidity, mortality and the durations of critical care and hospital stay. Twelve weeks after the discharge, participants will be interviewed to reassess quality of life and determine post-discharge healthcare utilisation. The costs associated with the exercise intervention and healthcare utilisation will be calculated.
  
  
  BACKGROUND
  Ethics approval was secured through Sunderland Research Ethics Committee. The findings of the trial will be disseminated through peer-reviewed journals, and national and international presentations.
  
  
  BACKGROUND
  Current Controlled Trials ISRCTN09433624.
authors.affiliation: York Trials Unit, Department of Health Sciences, University of York, York, UK.
authors.forename: Garry A
authors.initials: GA
authors.lastname: Tew
authors.forename: Matthew
authors.initials: M
authors.lastname: Weston
authors.forename: Elke
authors.initials: E
authors.lastname: Kothmann
authors.forename: Alan M
authors.initials: AM
authors.lastname: Batterham
authors.forename: Joanne
authors.initials: J
authors.lastname: Gray
authors.forename: Karen
authors.initials: K
authors.lastname: Kerr
authors.forename: Denis
authors.initials: D
authors.lastname: Martin
authors.forename: Shah
authors.initials: S
authors.lastname: Nawaz
authors.forename: David
authors.initials: D
authors.lastname: Yates
authors.forename: Gerard
authors.initials: G
authors.lastname: Danjoux
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D005081:Exercise Therapy; D005240:Feasibility Studies; D006801:Humans; D010809:Physical Fitness; D011300:Preoperative Care; D012107:Research Design
keywords: Aortic Aneurysm, Abdominal; Exercise; Feasibility Studies; Physical Fitness; Rehabilitation; Vascular Diseases