title: Evaluation of the haemodynamic characteristics of drug-eluting stents at implantation and at follow-up.
abstract: OBJECTIVE
  The aim of this study was to investigate the physiologic parameters: fractional flow reserve (FFR), hyperaemic trans-stent gradient (HTG), and wall shear stress (WSS) at implantation and at 6-month follow-up in the drug-eluting sirolimus stent and in its bare metal counterpart implanted in pairs within the same patient.
  
  
  RESULTS
  Twenty patients, accepted for percutaneous coronary intervention of at least two coronary arteries with comparable vessel and stenosis characteristics, received at random one sirolimus-eluting stent and one bare metal stent (BMS). Coronary pressure, FFR, HTG, and WSS were measured just after stent implantation and at 6-month follow-up. At 6-month follow-up, FFR was significantly higher in the sirolimus group compared with the bare metal group (0.91+/-0.05 vs. 0.83+/-0.10, P=0.027) and HTG was significantly lower (1.2+/-1.2 vs. 7.5+/-8.1 mmHg, P<0.001). In-stent WSS at 6 months remained normal in the sirolimus group but was elevated in the bare metal group (1.6+/-0.7 vs 3.9+/-3.1 Pa, respectively, P=0.003).
  
  
  CONCLUSIONS
  The physiologic characteristics of the drug-eluting sirolimus stents were superior to those of the equivalent BMS. Six months after implantation, FFR was significantly higher, HTG was significantly lower in arteries treated by a sirolimus stent, and normal WSS was maintained within the drug-eluting stent.
authors.affiliation: Department of Cardiology, Catharina Hospital, PO Box 1350, 5602 ZA Eindhoven, The Netherlands.
authors.forename: Marcel
authors.initials: M
authors.lastname: van't Veer
authors.forename: Nico H J
authors.initials: NH
authors.lastname: Pijls
authors.forename: Wilbert
authors.initials: W
authors.lastname: Aarnoudse
authors.forename: Jacques J
authors.initials: JJ
authors.lastname: Koolen
authors.forename: Frans N
authors.initials: FN
authors.lastname: van de Vosse
mesh_terms: D000787:Angina Pectoris / Q000188:drug therapy / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D023921:Coronary Stenosis / Q000188:drug therapy* / Q000503:physiopathology; D004343:Drug Implants; D005260:Female; D005500:Follow-Up Studies; D053805:Fractional Flow Reserve, Myocardial / Q000187:drug effects*; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008297:Male; D020123:Sirolimus / Q000008:administration & dosage*; D015607:Stents; D013314:Stress, Mechanical; D017539:Tunica Intima
chemical_list: D004343:Drug Implants; D007166:Immunosuppressive Agents; D020123:Sirolimus