Randomized comparison of the efficacy and safety of zotarolimus-eluting stents vs. sirolimus-eluting stents for percutaneous coronary intervention in chronic total occlusion--CAtholic Total Occlusion Study (CATOS) trial

Circ J. 2012;76(4):868-75. doi: 10.1253/circj.cj-11-1021. Epub 2012 Jan 25.


Background: Limited data are available regarding the direct comparison of angiographic and clinical outcomes after percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) for chronic total occlusion (CTO).

Methods and results: A prospective, randomized, multicenter trial was conducted to evaluate the non-inferiority of a zotarolimus-eluting stent (ZES; Endeavor Sprint®, n=80) to a sirolimus-eluting stent (SES; Cypher®, n=80) in patients with CTO lesion with a reference vessel diameter ≥ 2.5mm. The primary endpoint was in-segment binary restenosis rate at 9-month angiographic follow-up. Key secondary endpoints included target vessel failure (TVF; including cardiac death, myocardial infarction, and target vessel revascularization) and Academic Research Consortium-defined definite/probable stent thrombosis (ST) within 12 months. The ZES was non-inferior to the SES with respect to the primary endpoint, which occurred in 14.1% (95% confidence interval [CI]: 6.0-22.2) and in 13.7% (95%CI: 5.8-21.6) of patients, respectively (non-inferiority margin, 15.0%; P for non-inferiority <0.001). There were no significant between-group differences in the rate of TVF (10.0% vs. 17.5%; P=0.168) nor in the rate of ST (0.0% vs. 1.3%; P=0.316) during the 12-month clinical follow-up.

Conclusions: The effectiveness and safety of ZES are similar to those of SES and therefore it is a good treatment option in patients undergoing PCI for CTO with DESs.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Angioplasty, Balloon, Coronary / adverse effects
  • Angioplasty, Balloon, Coronary / instrumentation*
  • Angioplasty, Balloon, Coronary / mortality
  • Cardiovascular Agents / administration & dosage*
  • Chronic Disease
  • Coronary Angiography
  • Coronary Occlusion / diagnosis
  • Coronary Occlusion / mortality
  • Coronary Occlusion / therapy*
  • Coronary Restenosis / diagnosis
  • Coronary Restenosis / etiology
  • Drug-Eluting Stents*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / etiology
  • Prospective Studies
  • Prosthesis Design
  • Republic of Korea
  • Sirolimus / administration & dosage
  • Sirolimus / analogs & derivatives*
  • Thrombosis / diagnosis
  • Thrombosis / etiology
  • Time Factors
  • Treatment Outcome
  • Ultrasonography, Interventional


  • Cardiovascular Agents
  • zotarolimus
  • Sirolimus