title: Side branch occlusion after coronary stent implantation in patients presenting with ST-elevation myocardial infarction: clinical impact and angiographic predictors.
abstract: BACKGROUND
  The aim of this study was to assess the incidence and clinical outcome of the occlusion of major (> 1 mm) side branches following coronary stenting in patients undergoing percutaneous coronary intervention for acute ST-elevation myocardial infarction (STEMI).
  
  
  METHODS
  Among 276 consecutive patients presenting with STEMI, we found 80 patients (29%) with 101 stent-covered side branches. Clinical data and quantitative angiographic analysis were evaluated. Angiographic follow-up was available in 56 (70%) patients, and clinical follow-up could be completed in all patients.
  
  
  RESULTS
  Acute side branch occlusion after stent implantation (SBO) was observed in 10 (12.5%) patients involving 11 (10.9%) side branches. Predictors for SBO were: (1) reference side branch diameter at baseline < or = 1.4 mm; (2) ostial side branch stenosis > 50%; and (3) minimal side branch diameter at baseline < or = 0.6 mm. During hospitalization, in the SBO group, 2 patients died in cardiogenic shock and 1 underwent bypass surgery; no events were causally related to SBO. During long-term follow-up, 1 patient with SBO developed repeat MI as opposed to 7 patients in the non-SBO group who developed major adverse cardiac events (1 death, 6 repeat revascularizations).
  
  
  CONCLUSIONS
  The presence of a side branch originating from the target lesion in patients undergoing coronary stenting for acute STEMI is a frequent observation (29%) and is associated with a low incidence of side branch occlusion. Major predictors for SBO are the side branch size and the presence of an ostial side branch stenosis.
authors.affiliation: First Department of Medicine, University Hospital of Mannheim, Mannheim, Germany. stefan.kralev@med.ma.uni-heidelberg.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Kralev
authors.forename: Tudor C
authors.initials: TC
authors.lastname: Poerner
authors.forename: Daniel
authors.initials: D
authors.lastname: Basorth
authors.forename: Siegfried
authors.initials: S
authors.lastname: Lang
authors.forename: Christian
authors.initials: C
authors.lastname: Wolpert
authors.forename: Dariusch
authors.initials: D
authors.lastname: Haghi
authors.forename: Martin
authors.initials: M
authors.lastname: Borggrefe
authors.forename: Karl K
authors.initials: KK
authors.lastname: Haase
authors.forename: Tim
authors.initials: T
authors.lastname: Süselbeck
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy*; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D015607:Stents