title: Pacing Evaluation-Atrial SUpport Study in Cardiac Resynchronization Therapy (PEGASUS CRT): design and rationale.
abstract: BACKGROUND
  Cardiac resynchronization therapy (CRT) has been demonstrated to be an effective heart failure (HF) therapy. All pivotal trials of CRT to date have used atrial-synchronous biventricular pacing wherein there is no or minimal atrial pacing. In clinical practice, however, physicians often program CRT devices to have atrial rate support pacing, either by increasing the lower rate limit or by activating the rate sensor.
  
  
  OBJECTIVE
  The purpose of this study is to evaluate the effect of empiric atrial support pacing in patients with HF who have received a CRT defibrillator (CRT-D) device.
  
  
  METHODS
  PEGASUS CRT is a multicenter, 3-arm, randomized clinical trial of approximately 1200 patients receiving a CRT-D device. For the first 6 weeks after implant, devices are programmed to DDD with a lower rate limit of 40 beats/min. At 6 weeks, patients are randomized to DDD-40, DDD-70, or DDDR-40. All randomized patients are followed for 1 year, and at each visit, mortality, HF events, quality of life, New York Heart Association class, and atrial and ventricular arrhythmic episodes are evaluated. An exercise substudy will also be conducted, enrolling a minimum of 375 patients. Patients in this substudy will complete 2 cardiopulmonary exercise tests to evaluate the effect pacing mode has on exercise capacity. This randomized controlled trial will address whether empiric atrial support pacing is of clinical benefit to patients with HF who receive a CRT-D device.
authors.affiliation: Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA. martind3@ccf.org
authors.forename: David O
authors.initials: DO
authors.lastname: Martin
authors.forename: Kira Q
authors.initials: KQ
authors.lastname: Stolen
authors.forename: Scott
authors.initials: S
authors.lastname: Brown
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Yu
authors.forename: Christine
authors.initials: C
authors.lastname: Christie
authors.forename: Shephal K
authors.initials: SK
authors.lastname: Doshi
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Smith
authors.forename: Michael R
authors.initials: MR
authors.lastname: Gold
authors.forename: John D
authors.initials: JD
authors.lastname: Day
mesh_terms: D002304:Cardiac Pacing, Artificial; D017147:Defibrillators, Implantable; D017079:Exercise Tolerance; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D011446:Prospective Studies; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D012107:Research Design