title: Impact of stenting and oral sirolimus on endothelium-dependent and independent coronary vasomotion.
abstract: BACKGROUND
  There is no consensus regarding the impact of stenting on long-term endothelial function. There have been reports of increased endothelial dysfunction with sirolimus-eluting stents as compared to bare metal stenting (BMS).
  
  
  OBJECTIVE
  This study aims to assess the impact of BMS and the effect of oral sirolimus on endothelial function.
  
  
  METHODS
  Forty-five patients were randomized into three groups: BMS + high-dose oral sirolimus (initial dose of 15 mg, followed by 6 mg/day for four weeks); BMS + low-dose sirolimus (6 mg followed by 2 mg daily for four weeks); and BMS without sirolimus. Changes in vasoconstriction or vasodilation in a 15 mm segment starting at the distal stent end in response to acetylcholine and nitroglycerin were assessed by quantitative angiography.
  
  
  RESULTS
  The groups had similar angiographic characteristics. The percent variation in diameter in response to acetylcholine was similar in all groups at the two time points (p = 0.469). Four hours after stenting, the target segment presented an endothelial dysfunction that was maintained after eight months in all groups. In all groups, endothelium-independent vasomotion in response to nitroglycerin was similar at four hours and eight months, with increased target segment diameter after nitroglycerin infusion (p = 0.001).
  
  
  CONCLUSIONS
  The endothelial dysfunction was similarly present at the 15 mm segment distal to the treated segment, at 4 hours and 8 months after stenting. Sirolimus administered orally during 4 weeks to prevent restenosis did not affect the status of endothelium-dependent and independent vasomotion.
authors.affiliation: Hospital São Paulo - SPDM - Universidade Federal de São Paulo, São Paulo, SP, Brazil. rosley@uol.com.br
authors.forename: Rósley Weber Alvarenga
authors.initials: RW
authors.lastname: Fernandes
authors.forename: João Miguel
authors.initials: JM
authors.lastname: Dantas
authors.forename: Dinaldo Cavalcanti
authors.initials: DC
authors.lastname: Oliveira
authors.forename: Hiram Grando
authors.initials: HG
authors.lastname: Bezerra
authors.forename: Fabio Sandoli
authors.initials: FS
authors.lastname: Brito
authors.forename: Valter C
authors.initials: VC
authors.lastname: Lima
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology / Q000627:therapeutic use; D000284:Administration, Oral; D000328:Adult; D000704:Analysis of Variance; D003331:Coronary Vessels / Q000187:drug effects* / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000494:pharmacology / Q000627:therapeutic use; D020123:Sirolimus / Q000008:administration & dosage / Q000494:pharmacology*; D015607:Stents / Q000009:adverse effects*; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology; D014665:Vasodilator Agents / Q000494:pharmacology / Q000627:therapeutic use; D014666:Vasomotor System / Q000187:drug effects* / Q000503:physiopathology
chemical_list: D007166:Immunosuppressive Agents; D014665:Vasodilator Agents; D005996:Nitroglycerin; D000109:Acetylcholine; D020123:Sirolimus