title: Clinical verification of a theory for predicting side branch stenosis after main vessel stenting in coronary bifurcation lesions.
abstract: OBJECTIVE
  To verify in a clinical scenario a theory for predicting side branch (SB) stenosis after main vessel stent implantation in coronary bifurcation lesions.
  
  
  BACKGROUND
  Many unresolved issues remain regarding SB compromise when the parent vessel is stented.
  
  
  METHODS
  Bifurcation lesions (all Medina types) were subjected to angiographic analysis to determine the angle, defined as alpha, between the axes of the parent vessel and the SB. Using the prediction that the percent diameter stenosis (%DS) is equal to the cosine of angle alpha and relating it to a formula to determine the minimal lumen diameter (MLD) led to the following equation: MLD = ds x (1 -cos alpha); ds refers to the diameter of the SB. The predicted and observed SB stenosis values following angiography were compared.
  
  
  RESULTS
  Fifty-two patients with 57 lesions were included in the analysis. Patient demographics and characteristics were similar to those in previous studies. There was a high coefficient of determination between the predicted and observed values of %DS (r(2)= 0.82, P < 0.001) and MLD (r(2)= 0.86, P < 0.001). We determined a cutoff value of 70% for predicted %DS for SB closure. When using multivariate regression analysis, the only predictor of SB ostial stenosis after stenting was alpha angle, whereas the predictors of MLD included the angle alpha and the RVD of the SB.
  
  
  CONCLUSIONS
  Our analysis shows that the most powerful independent predictor of SB compromise is a new variable angle alpha.
authors.affiliation: Invasive Cardiology Department, Central Hospital of the Internal Affairs and Administration Ministry, Warsaw, Poland. dobrinv@mail.bg
authors.forename: Dobrin
authors.initials: D
authors.lastname: Vassilev
authors.forename: Robert
authors.initials: R
authors.lastname: Gil
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006328:Cardiac Catheterization; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000628:therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D015607:Stents