title: Increased serum bilirubin level is related to good collateral development in patients with chronic total coronary occlusion.
abstract: OBJECTIVE
  Bilirubin is a bile pigment with potent anti-oxidant properties; in previous studies it has been reported to be negatively associated with coronary artery disease (CAD). Although elevated serum bilirubin concentrations may protect against endothelial dysfunction, it is not clear whether higher serum bilirubin levels (SBLs) in physiological ranges may work in favor of good collateral development in patients with chronic total coronary occlusion (CTO).
  
  
  METHODS
  The study population consisted of patients who underwent coronary angiography with a suspicion of CAD. Patients who had CTO in at least one major coronary artery were included. Coronary angiograms of 179 eligible patients from our database were reanalyzed and 110 of them had good collateral development and 69 had poor collateral development according to the Cohen-Rentrop method.
  
  
  RESULTS
  Patients with good collateral development had a lower fasting plasma glucose level (FPG) (p=0.024) and higher SBLs in comparison to patients with poor collateral development (p<0.001). The number of CTO vessels (p=0.013) and left ventricular ejection fraction (EF%) were higher in good collateral group than poor collateral group (p=0.017). In multivariate analysis, FPG negatively (odds ratio [OR]: 0.981, p=0.003) and SBL (OR for per 0.1-mg/dL increase: 1.832, p<0.001) and the number of CTO vessels (OR: 5.642, p=0.007) were positively related to coronary collateral development.
  
  
  CONCLUSIONS
  This study suggests that higher bilirubin levels within relatively normal ranges were related with favorable coronary collateral growth in patients with CTO. SBL may be responsible for the difference in coronary collateral vessel development among different patients with coronary artery disease. The anti-inflammatory and anti-oxidant properties of bilirubin may mediate this effect.
authors.affiliation: Department of Cardiology, Rize University Medical Faculty, Turkey.
authors.forename: Turan
authors.initials: T
authors.lastname: Erdogan
authors.forename: Yüksel
authors.initials: Y
authors.lastname: Ciçek
authors.forename: Sinan Altan
authors.initials: SA
authors.lastname: Kocaman
authors.forename: Aytun
authors.initials: A
authors.lastname: Canga
authors.forename: Mustafa
authors.initials: M
authors.lastname: Cetin
authors.forename: Emre
authors.initials: E
authors.lastname: Durakoglugil
authors.forename: Omer
authors.initials: O
authors.lastname: Satiroglu
authors.forename: Ahmet
authors.initials: A
authors.lastname: Temiz
authors.forename: Elif
authors.initials: E
authors.lastname: Ergül
authors.forename: Ismail
authors.initials: I
authors.lastname: Sahin
authors.forename: Mehmet
authors.initials: M
authors.lastname: Bostan
mesh_terms: D000368:Aged; D001663:Bilirubin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D002908:Chronic Disease; D003097:Collateral Circulation / Q000502:physiology*; D054059:Coronary Occlusion / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers; D001663:Bilirubin