title: Modifying effect of dual antiplatelet therapy on incidence of stent thrombosis according to implanted drug-eluting stent type.
abstract: OBJECTIVE
  To investigate the putative modifying effect of dual antiplatelet therapy (DAPT) use on the incidence of stent thrombosis at 3 years in patients randomized to Endeavor zotarolimus-eluting stent (E-ZES) or Cypher sirolimus-eluting stent (C-SES).
  
  
  RESULTS
  Of 8709 patients in PROTECT, 4357 were randomized to E-ZES and 4352 to C-SES. Aspirin was to be given indefinitely, and clopidogrel/ticlopidine for ≥ 3 months or up to 12 months after implantation. Main outcome measures were definite or probable stent thrombosis at 3 years. Multivariable Cox regression analysis was applied, with stent type, DAPT, and their interaction as the main outcome determinants. Dual antiplatelet therapy adherence remained the same in the E-ZES and C-SES groups (79.6% at 1 year, 32.8% at 2 years, and 21.6% at 3 years). We observed a statistically significant (P = 0.0052) heterogeneity in treatment effect of stent type in relation to DAPT. In the absence of DAPT, stent thrombosis was lower with E-ZES vs. C-SES (adjusted hazard ratio 0.38, 95% confidence interval 0.19, 0.75; P = 0.0056). In the presence of DAPT, no difference was found (1.18; 0.79, 1.77; P = 0.43).
  
  
  CONCLUSIONS
  A strong interaction was observed between drug-eluting stent type and DAPT use, most likely prompted by the vascular healing response induced by the implanted DES system. These results suggest that the incidence of stent thrombosis in DES trials should not be evaluated independently of DAPT use, and the optimal duration of DAPT will likely depend upon stent type (Clinicaltrials.gov number NCT00476957).
authors.affiliation: University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva, Switzerland edoardo@camenzind-cardio.net.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Camenzind
authors.affiliation: Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.affiliation: Cardiovascular Center, OLV Hospital, Aalst, Belgium.
authors.forename: William
authors.initials: W
authors.lastname: Wijns
authors.affiliation: Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Mauri
authors.affiliation: Cardialysis, Rotterdam, the Netherlands.
authors.forename: Tessa
authors.initials: T
authors.lastname: Rademaker-Havinga
authors.affiliation: Manchester Royal Infirmary Hospital, Manchester, UK.
authors.forename: Farzin Fath
authors.initials: FF
authors.lastname: Ordoubadi
authors.affiliation: St Antonius Ziekehuis, Nieuwegein, the Netherlands.
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Suttorp
authors.affiliation: Prince Salman Cardiac Center, King Fahd Medical City, Riyad, Saudi Arabia.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Al Kurdi
authors.affiliation: Université Paris-Diderot, Sorbonne-Paris Cité, Paris, France INSERM U-698, Paris, France Département Hospitalo-Universitaire FIRE, Hôpital Bichat, Assistance Publique - Hôpitaux de Paris, Paris, France NHLI Imperial College, ICMS, Royal Brompton Hospital, London, UK.
authors.forename: Ph Gabriel
authors.initials: PG
authors.lastname: Steg
mesh_terms: D001241:Aspirin / Q000627:therapeutic use; D001807:Blood Vessel Prosthesis; D000077144:Clopidogrel; D023903:Coronary Restenosis / Q000517:prevention & control; D003328:Coronary Thrombosis / Q000517:prevention & control*; D054855:Drug-Eluting Stents; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006083:Graft Occlusion, Vascular / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011446:Prospective Studies; D011475:Prosthesis Failure / Q000009:adverse effects*; D020123:Sirolimus / Q000031:analogs & derivatives / Q000627:therapeutic use; D013988:Ticlopidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; C489443:zotarolimus; D013988:Ticlopidine; D001241:Aspirin; D020123:Sirolimus
keywords: Drug-eluting stent; Dual antiplatelet therapy; Endothelialization; Healing; Sirolimus; Stent thrombosis; Zotarolimus