title: Late thrombosis after double versus single drug-eluting stent in the treatment of coronary bifurcations: a meta-analysis of randomized and observational Studies.
abstract: OBJECTIVE
  This study sought to hypothesize that the higher risk of myocardial infarction (MI) documented after a routine double drug-eluting stent (DES) strategy (DDS) compared with a single DES strategy (SDS) with provisional stenting in percutaneous coronary interventions (PCI) of bifurcation lesions is driven by an increased rate of DES thrombosis.
  
  
  BACKGROUND
  The results of currently available randomized, controlled trials (RCTs) were inconclusive in the choice between SDS and DDS. Meta-analyses have shown an increased risk of MI in the DDS group, without identifying the underlying mechanism(s).
  
  
  METHODS
  We performed a meta-analysis of 12 major (>100 patients) studies of bifurcation DES PCI: 5 RCTs and 7 nonrandomized observational studies, for a total of 6,961 patients. Random-effects models were used to calculate summary risk ratios (RRs). As a primary endpoint, we assessed the RRs and 95% confidence intervals (CIs) of definite DES thrombosis; death, MI, and target vessel revascularization (TVR) were evaluated as secondary endpoints.
  
  
  RESULTS
  Compared with SDS, DDS had an increased risk of DES thrombosis (RR: 2.31; 95% CI: 1.33 to 4.03) and MI (RR: 1.86; 95% CI: 1.34 to 2.60). Mortality (RR: 1.18; 95% CI: 0.85 to 1.65) and TVR (RR: 1.02; 95% CI: 0.80 to 1.30) were similar. The RRs of MI and DES thrombosis were associated (p = 0.040).
  
  
  CONCLUSIONS
  In PCI of coronary bifurcations, SDS should be the preferred approach, as DDS is associated with an increased risk of MI, likely driven by DES thrombosis.
authors.affiliation: Institute of Cardiology and Center of Excellence on Aging, Chieti, Italy. m.zimarino@unich.it
authors.forename: Marco
authors.initials: M
authors.lastname: Zimarino
authors.forename: Alessandro
authors.initials: A
authors.lastname: Corazzini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Ricci
authors.forename: Marta
authors.initials: M
authors.lastname: Di Nicola
authors.forename: Raffaele
authors.initials: R
authors.lastname: De Caterina
mesh_terms: D016009:Chi-Square Distribution; D003324:Coronary Artery Disease / Q000401:mortality / Q000628:therapy*; D003328:Coronary Thrombosis / Q000209:etiology* / Q000401:mortality; D054855:Drug-Eluting Stents; D019317:Evidence-Based Medicine; D006801:Humans; D016014:Linear Models; D009203:Myocardial Infarction / Q000209:etiology; D064887:Observational Studies as Topic; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects* / Q000295:instrumentation* / Q000401:mortality; D011474:Prosthesis Design; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: CI; DDS; DES; MI; PCI; RCT; RR; SDS; TVR; confidence interval; coronary bifurcation; double drug-eluting stent strategy; drug-eluting stent thrombosis; drug-eluting stent(s); myocardial infarction; nROS; nonrandomized, observational study; percutaneous coronary intervention; randomized, controlled trial; relative risk; single drug-eluting stent strategy; target vessel revascularization