title: The impact of ligation of proximal side branches on blood flow and functional status of the internal thoracic artery in coronary anastomosis.
abstract: BACKGROUND
  The effect of proximal side branches on the patency of the internal thoracic artery (ITA) is controversial. We used echocardiography and Doppler to verify the effect of ligation of branches on the flow and coronary flow reserve (CFR) of the grafted ITA in patients after coronary artery bypass grafting (CABG).
  
  
  METHODS
  We prospectively investigated 53 patients with preserved left ventricular ejection fraction (LVEF >50%) who underwent CABG of the ITA. In Group I (25 patients), major branches were ligated during ITA anastomosis to the left anterior descending (LAD) coronary artery, whereas no ligation was performed in Group II (28 patients). Systolic flow (SF), diastolic flow (DF), and total flow (TF = SF + DF) were measured by Doppler echocardiography at the proximal level of the ITA preoperatively, at early postoperative stage, and 6 months after surgery. Dobutamine stress echocardiography (DSE) was performed at 6 months to determine CFR.
  
  
  RESULTS
  The ITA flow was predominantly systolic before surgery and diastolic in the postoperative period. We found no differences between the groups in DF. On DSE, SF (19.5±9 mL/min vs 32.7±19 mL/min; P=.003) and TF (79±21 mL/min vs 101±47 mL/min; P=.037) were higher in Group II. There were no differences in CFR (1.9±0.46 vs 2.11±0.56; P=.143).
  
  
  CONCLUSIONS
  In patients with preserved LVEF, ligation of major side branches during anastomosis to the LAD does not alter ITA flow or CFR.
authors.affiliation: Public Health Department, State University of Ceará, Fortaleza, Brazil.|Prontocárdio Hospital, Fortaleza, Brazil.|Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: José Sebastião
authors.initials: JS
authors.lastname: Abreu
authors.affiliation: Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Jeane Mike
authors.initials: JM
authors.lastname: Tsutsui
authors.affiliation: Messejana's Heart and Lung Hospital, Fortaleza, Brazil.
authors.forename: Sandra Nívea R
authors.initials: SN
authors.lastname: Falcão
authors.affiliation: Prontocárdio Hospital, Fortaleza, Brazil.
authors.forename: José Acácio
authors.initials: JA
authors.lastname: Feitosa
authors.affiliation: Prontocárdio Hospital, Fortaleza, Brazil.
authors.forename: Eduardo Arraes
authors.initials: EA
authors.lastname: Rocha
authors.affiliation: Messejana's Heart and Lung Hospital, Fortaleza, Brazil.
authors.forename: Ítalo Martins
authors.initials: ÍM
authors.lastname: Oliveira
authors.affiliation: Prontocárdio Hospital, Fortaleza, Brazil.
authors.forename: Teresa Cristina
authors.initials: TC
authors.lastname: Diógenes
authors.affiliation: Prontocárdio Hospital, Fortaleza, Brazil.
authors.forename: José N
authors.initials: JN
authors.lastname: Paes
authors.affiliation: Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: João C
authors.initials: JC
authors.lastname: Sbano
authors.affiliation: Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Dallan
authors.affiliation: Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Roberto Kalil
authors.initials: RK
authors.lastname: Filho
authors.affiliation: Program in Cardiology, Faculty of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Wilson
authors.initials: W
authors.lastname: Mathias
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation / Q000502:physiology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008026:Ligation; D008297:Male; D008323:Mammary Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008875:Middle Aged; D011446:Prospective Studies; D012039:Regional Blood Flow / Q000502:physiology*; D018608:Ultrasonography, Doppler; D014654:Vascular Patency
keywords: Doppler echocardiography; coronary flow reserve; internal thoracic artery; stress echocardiography