title: Stent thrombosis after drug-eluting stent implantation: incidence, timing, and relation to discontinuation of clopidogrel therapy over a 4-year period.
abstract: OBJECTIVE
  To assess the incidence, timing, and relation of drug-eluting stent (DES) thrombosis to discontinuation of clopidogrel therapy.
  
  
  RESULTS
  This prospective observational cohort study included 6816 consecutive patients that underwent successful DES implantation. Primary endpoint was definite stent thrombosis (ST). During 4 years of follow-up, definite ST was observed in 73 patients, corresponding to a cumulative incidence of 1.2%. Cumulative incidence of ST at 30 days was 0.5 and 0.8% at 1 year, respectively. Discontinuation of clopidogrel therapy was significantly associated with ST only in the first 6 months after the procedure (P < 0.001). During that period, the median time interval from clopidogrel discontinuation to ST was 9 days [interquartile range (IQR) 5.5-22.5] while thereafter it was 104.3 days (IQR 7.4-294.8).
  
  
  CONCLUSIONS
  The 4 year incidence of ST after DES implantation is low. A relevant number of ST occur early after discontinuation of clopidogrel therapy. The dependence of ST on discontinuation of clopidogrel therapy seems to be mostly confined to the first 6 months after DES implantation. However, specifically designed randomized studies are required to establish the optimal length of clopidogrel therapy after DES implantation.
authors: Deutsches Herzzentrum, Technische Universität, Lazarettstrasse 36, Munich, Germany. schulzs@dhm.mhn.de
authors: Stefanie
authors: S
authors: Schulz
authors: Tibor
authors: T
authors: Schuster
authors: Julinda
authors: J
authors: Mehilli
authors: Robert A
authors: RA
authors: Byrne
authors: Julia
authors: J
authors: Ellert
authors: Steffen
authors: S
authors: Massberg
authors: Julia
authors: J
authors: Goedel
authors: Olga
authors: O
authors: Bruskina
authors: Kurt
authors: K
authors: Ulm
authors: Albert
authors: A
authors: Schömig
authors: Adnan
authors: A
authors: Kastrati
mesh_terms: D000368:Aged; D001807:Blood Vessel Prosthesis; D000077144:Clopidogrel; D017023:Coronary Angiography; D054855:Drug-Eluting Stents; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D011446:Prospective Studies; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine