title: Recovery of linear and nonlinear heart rate dynamics after coronary artery bypass grafting surgery.
abstract: BACKGROUND
  Conventional coronary artery bypass grafting (C-CABG) and off-pump CABG (OPCAB) surgery may produce different patients' outcomes, including the extent of cardiac autonomic (CA) imbalance. The beneficial effects of an exercise-based inpatient programme on heart rate variability (HRV) for C-CABG patients have already been demonstrated by our group. However, there are no studies about the impact of a cardiac rehabilitation (CR) on HRV behaviour after OPCAB. The aim of this study is to compare the influence of both operative techniques on HRV pattern following CR in the postoperative (PO) period.
  
  
  METHODS
  Cardiac autonomic function was evaluated by HRV indices pre- and post-CR in patients undergoing C-CABG (n = 15) and OPCAB (n = 13). All patients participated in a short-term (approximately 5 days) supervised CR programme of early mobilization, consisting of progressive exercises, from active-assistive movements at PO day 1 to climbing flights of stairs at PO day 5.
  
  
  RESULTS
  Both groups demonstrated a reduction in HRV following surgery. The CR programme promoted improvements in HRV indices at discharge for both groups. The OPCAB group presented with higher HRV values at discharge, compared to the C-CABG group, indicating a better recovery of CA function.
  
  
  CONCLUSIONS
  Our data suggest that patients submitted to OPCAB and an inpatient CR programme present with greater improvement in CA function compared to C-CABG.
authors.affiliation: Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Federal University of São Carlos, São Carlos, Brazil.
authors.forename: Camila Bianca Falasco
authors.initials: CB
authors.lastname: Pantoni
authors.forename: Renata Gonçalves
authors.initials: RG
authors.lastname: Mendes
authors.forename: Luciana
authors.initials: L
authors.lastname: Di Thommazo-Luporini
authors.forename: Rodrigo Polaquini
authors.initials: RP
authors.lastname: Simões
authors.forename: Othon
authors.initials: O
authors.lastname: Amaral-Neto
authors.forename: Ross
authors.initials: R
authors.lastname: Arena
authors.forename: Solange
authors.initials: S
authors.lastname: Guizilini
authors.forename: Walter José
authors.initials: WJ
authors.lastname: Gomes
authors.forename: Aparecida Maria
authors.initials: AM
authors.lastname: Catai
authors.forename: Audrey
authors.initials: A
authors.lastname: Borghi-Silva
mesh_terms: D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001938:Brazil; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000534:rehabilitation*; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000534:rehabilitation*; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects / Q000534:rehabilitation*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D004434:Early Ambulation; D005081:Exercise Therapy; D005260:Female; D006321:Heart / Q000294:innervation*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics; D011446:Prospective Studies; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome
keywords: autonomic nervous system; cardiopulmonary bypass; inpatient rehabilitation; myocardial revascularization surgery; physiotherapy