title: Low coronary flow velocity and shear stress predict restenosis after sirolimus-eluting stent implantation.
abstract: OBJECTIVE
  This study sought to assess predictive values of coronary flow velocity and an index of shear stress throughout the vessel for angiographic restenosis after sirolimus-eluting stent implantation.
  
  
  METHODS
  The study patients underwent successful implantation of a sirolimus-eluting stent for de novo lesions located in native coronary vessels and underwent follow-up angiography 6-9 months later. The TIMI frame count method and quantitative digital angiographic analysis were performed based on the post-stenting angiogram. Coronary flow velocity and Reynolds number, an index of shear stress, were measured.
  
  
  RESULTS
  Post-stenting digital angiograms from 267 patients were analyzed. We divided the study patients into two groups: a Restenosis group with 21 patients and a Non-Restenosis group with 246 patients. The Restenosis group indicated significantly lower coronary flow velocity (137.7+/-35.6 mm/sec versus 241.1+/-72.9 mm/sec, p = 0.0001) and lower Reynolds number (107.0+/-35.8 versus 199.2+/-67.1, p = 0.0001) than did the Non-Restenosis group.
  
  
  CONCLUSIONS
  Lowered coronary flow velocity and shear stress after sirolimus-eluting stenting may predict the risk of restenosis.
authors.affiliation: Cardiovascular Center, Yokosuka Kyosai Hospital, Yokosuka, Kanagawa, Japan. hhikita-circ@umin.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hikita
authors.forename: Akira
authors.initials: A
authors.lastname: Sato
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nozato
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kawashima
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Taishi
authors.initials: T
authors.lastname: Kuwahara
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takahashi
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000295:instrumentation*; D001783:Blood Flow Velocity; D002317:Cardiovascular Agents / Q000008:administration & dosage*; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D003326:Coronary Circulation; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors; D020123:Sirolimus / Q000008:administration & dosage*; D013314:Stress, Mechanical; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D002317:Cardiovascular Agents; D020123:Sirolimus