title: Early angiographic changes of side branches arising from a Palmaz-Schatz stented coronary segment: results and clinical implications.
abstract: OBJECTIVE
  The purpose of this study was to assess the effects and clinical implications of Palmaz-Schatz stent implantation on coronary blood flow in side branches arising from a stented coronary artery segment.
  
  
  BACKGROUND
  The occlusion of a side branch is a well defined risk after balloon angioplasty. However, the impact of stenting on the coronary flow in side branches arising within the stented segment is unknown.
  
  
  METHODS
  Forty-six stented coronary artery segments with 79 side branches emerging from the stented segment were analyzed. Angiographic studies were performed before angioplasty, after balloon dilation, immediately after stenting and 24 h later. Side branches were classified as follows: type A (> or = 1 mm in diameter, with ostial narrowing), type B (> or = 1 mm in diameter, without ostial narrowing), type C (< 1 mm in diameter, with ostial narrowing) and type D (< 1 mm in diameter, without ostial narrowing). Quantitative angiography was used to assess the diameter of the side branches.
  
  
  RESULTS
  Stents were implanted electively in lesions with restenosis (41 stents, 89%) or with a suboptimal result after angioplasty (5 stents, 11%). Nine side branches (11%) were type A, 25 (32%) type B, 7 (9%) type C and 38 (48%) type D. At baseline, 68 side branches had Thrombolysis in Myocardial Infarction (TIMI) trial flow grade 3; 10 had grade 2; and 1 had grade 1. Flow worsened (TIMI grade > or = 1) in six side branches (8%) after balloon dilation and in four side branches (5%) after stenting. One additional side branch (1%) was occluded at 24 h. Of the 34 side branches > or = 1 mm in diameter (mean diameter 1.5 +/- 0.3 mm), 2 (6%) had flow impairment after stenting. Three patients experienced transient angina, but no acute myocardial infarction occurred as a result of a side branch occlusion.
  
  
  CONCLUSIONS
  Coronary artery stenting does not modify anterograde flow in 90% of side branches. Coronary flow is reduced after stenting in a few branches, but this does not appear to have major clinical relevance.
authors.affiliation: Cardiopulmonary Department, Hospital Universitario San Carlos, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Iñiguez
authors.forename: C
authors.initials: C
authors.lastname: Macaya
authors.forename: F
authors.initials: F
authors.lastname: Alfonso
authors.forename: J
authors.initials: J
authors.lastname: Goicolea
authors.forename: R
authors.initials: R
authors.lastname: Hernandez
authors.forename: P
authors.initials: P
authors.lastname: Zarco
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D003251:Constriction, Pathologic / Q000209:etiology; D017023:Coronary Angiography; D003326:Coronary Circulation; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D003331:Coronary Vessels / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015607:Stents / Q000009:adverse effects*