title: Heart rate turbulence for predicting new-onset atrial fibrillation in patients undergoing coronary artery bypass grafting.
abstract: BACKGROUND
  Cardiac autonomic dysfunction reportedly contributes to the AF triggering and maintenance. Heart rate turbulence (HRT) is a promising noninvasive measure of cardiac autonomic function. We investigated whether ambulatory ECG-based HRT measurement could predict in-hospital new-onset atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery.
  
  
  METHODS
  HRT onset (TO) and slope (TO) were prospectively measured from 24-h Holter recording in 113 consecutive patients prior to CABG. Abnormal HRT was defined as at least one abnormal value in TO (> 0%) and TS (< 2.5 ms/RR).
  
  
  RESULTS
  Patients with abnormal HRT (n = 60) showed a significantly higher AF incidence (47% versus 21%, P = 0.005) and AF burden (29 ± 9 versus 7 ± 5 h, P = 0.043) than those with normal HRT (n = 53). Abnormal HRT were identified as independent predictors for the new-onset postoperative AF. During the follow-up period (12.0 ± 10.5 months), the abnormal HRT group showed a worse prognosis versus the normal HRT group regarding the AF recurrence/postoperative stroke (P = 0.018). Additionally, the postoperative AF incidence, in-hospital AF burden, and the rate of AF recurrence/postoperative stroke gradually elevated as the number of abnormal HRT values increased from 0 to 2.
  
  
  CONCLUSIONS
  Preoperative abnormal HRT was significantly associated with worse short-term (in-hospital new-onset AF) and long-term outcomes (post-discharge AF recurrence/postoperative stroke) after CABG surgery. Additional studies incorporating preventive interventions depending on the preoperative HRT results might be worthwhile in this patient group.
authors.affiliation: Department of Internal Medicine, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Seung-Jung
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Young Keun
authors.initials: YK
authors.lastname: On
authors.affiliation: Department of Internal Medicine, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: juneskim@skku.edu.
authors.forename: June Soo
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Thoracic and Cardiovascular Surgery, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Dong Seop
authors.initials: DS
authors.lastname: Jeong
authors.affiliation: Thoracic and Cardiovascular Surgery, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Wook Sung
authors.initials: WS
authors.lastname: Kim
authors.affiliation: Thoracic and Cardiovascular Surgery, Cardiac and Vascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Young Tak
authors.initials: YT
authors.lastname: Lee
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018879:Ventricular Premature Complexes / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology
keywords: Atrial fibrillation; Cardiac autonomic function; Coronary artery bypass graft surgery; Heart rate turbulence