title: Decreased postoperative atrial fibrillation following cardiac transplantation: the significance of autonomic denervation.
abstract: BACKGROUND
  Endocardial ablation approaches targeting the retroatrial cardiac ganglia to treat atrial fibrillation (AF) have been proposed. However, the potential value using this approach is unknown. Disruption of the autonomic inputs with orthotropic heart transplant (OHT) provides a unique opportunity to study the effects of autonomic innervation on AF genesis and maintenance. We hypothesized that due to denervation, the risk of postoperative AF would be lower following OHT compared to surgical maze even though both groups get isolation of the pulmonary veins.
  
  
  RESULTS
  We reviewed 155 OHTs (mean age 52 ± 11 years, 72% males) and used 1:1 age-, sex-, and date-of-surgery-matched two control groups from patients undergoing surgical maze or only coronary artery bypass grafting (CABG). Using conditional logistic regression we compared the odds of AF within 2 weeks following OHT versus controls. Postoperative AF occurred in 10/155 (6.5%) OHT patients. The conditional odds of postoperative AF were lower for OHT as compared to controls (vs maze: odds ratio [OR] 0.27 [95% confidence interval (CI) 0.13-0.57], vs CABG: OR 0.38 [0.17-0.81], P = 0.003; and on additional adjustment for left atrial enlargement, vs maze: OR 0.28 [0.13-0.60], vs CABG: OR 0.14 [0.04-0.47], P = 0.0009).
  
  
  CONCLUSIONS
  Risk of postoperative AF is significantly lower with OHT as in comparison to surgical maze. As both surgeries entail isolation of the pulmonary veins but only OHT causes disruption of autonomic innervation, this observation supports a mechanistic role of autonomic nervous system in AF. The benefit of targeting the cardiac autonomic system to treat AF needs further investigation.
authors: Division of Cardiology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors: Amit
authors: A
authors: Noheria
authors: Sandeep M
authors: SM
authors: Patel
authors: Sultan
authors: S
authors: Mirzoyev
authors: Malini
authors: M
authors: Madhavan
authors: Paul A
authors: PA
authors: Friedman
authors: Douglas L
authors: DL
authors: Packer
authors: Richard C
authors: RC
authors: Daly
authors: Sudhir S
authors: SS
authors: Kushwaha
authors: Brooks S
authors: BS
authors: Edwards
authors: Samuel J
authors: SJ
authors: Asirvatham
mesh_terms: D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000517:prevention & control*; D017763:Autonomic Denervation / Q000706:statistics & numerical data*; D003131:Combined Modality Therapy / Q000706:statistics & numerical data; D015897:Comorbidity; D005260:Female; D016027:Heart Transplantation / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology* / Q000517:prevention & control*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome