title: Relationship between integrated backscatter and atrial fibrosis in patients with and without atrial fibrillation who are undergoing coronary bypass surgery.
abstract: OBJECTIVE
  The purpose of this study was to investigate the relationship between the integrated backscatter (IBS) and atrial fibrosis, with and without atrial fibrillation (AF), in patients who are undergoing coronary bypass grafting (CABG).
  
  
  METHODS
  A total of 74 patients (18 preoperative AF, 56 sinus rhythm [SR]) with coronary artery disease undergoing CABG were included. The IBS of the left atrium (LA) posterior wall was acquired from transthoracic echocardiographic examination before surgery. Samples from the LA appendage were collected after opening the pericardium and quantitative assessment of atrial fibrosis was performed with collagen volume fraction (CVF). Postoperative AF was monitored with electrocardiographic telemetry in-hospital.
  
  
  RESULTS
  There was a positive relationship between age, IBS of the left atrial posterior wall indexed by pericardium (IBS%), and CVF by multivariate linear regression analysis (r = 0.612, p = 0.034; r = 0.887, p < 0.001 respectively). The value of IBS%, LA dimension (LAD), and CVF values were higher in patients with preoperative AF than in patients with preoperative SR (p < 0.001, p < 0.01, p < 0.001, respectively). The value of age, IBS%, and CVF in patients with postoperative AF were higher than in patients without postoperative AF (p = 0.029, p < 0.001, p = 0.001 respectively).
  
  
  CONCLUSIONS
  IBS of the LA posterior wall indexed by pericardium provides an objective quantitative measure of atrial fibrosis and correlates with postoperative AF in patients undergoing CABG surgery.
authors: Heart and Vessel Centre, Beijing Friendship Hospital, Capital Medical University, Beijing, China. lukewang1972@sohu.com.cn
authors: Guo-Dong
authors: GD
authors: Wang
authors: Lu-Hua
authors: LH
authors: Shen
authors: Lei
authors: L
authors: Wang
authors: Hong-Wei
authors: HW
authors: Li
authors: Yu-Chen
authors: YC
authors: Zhang
authors: Hui
authors: H
authors: Chen
mesh_terms: D000367:Age Factors; D000368:Aged; D020517:Atrial Appendage / Q000473:pathology; D001281:Atrial Fibrillation / Q000150:complications / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D001706:Biopsy; D001026:Coronary Artery Bypass / Q000009:adverse effects; D003324:Coronary Artery Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D004452:Echocardiography; D015716:Electrocardiography, Ambulatory; D005260:Female; D005355:Fibrosis; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D013686:Telemetry; D016896:Treatment Outcome