Optimal Strategy for Side Branch Stenting in Coronary Bifurcation Lesion

• Cardiac death [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  All deaths were considered cardiac unless a definite non-cardiac cause could be established.
• Myocardial infarction (MI) [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  MI was defined as elevated cardiac enzymes (troponin or MB fraction of creatine kinase, CK-MB) more than the upper limit of the normal value with ischemic symptoms or electrocardiography findings indicative of ischemia that was not related to the index procedure.
• Target vessel revascularization (TVR) [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  TVR was repeat revascularization of the target vessel by PCI or bypass graft surgery.
• Target lesion revascularization (TLR) [ Time Frame: 12 months ] [ Designated as safety issue: No ]
  TLR was defined as repeat PCI of the lesion within 5 mm of stent deployment or bypass graft surgery of the target vessel.
• Stent thrombosis [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  Stent thrombosis was assessed based on the definitions of the Academic Research Consortium as definite, probable, or possible stent thrombosis.
• Periprocedural enzyme elevation [ Time Frame: during the hospitalization ] [ Designated as safety issue: No ]
  Periprocedural enzyme elevation was defined as a rise in CK-MB ≥3 times the upper normal limit after the index procedure.
• the incidence of binary angiographic restenosis in the main branch and side branch [ Time Frame: 9 months ] [ Designated as safety issue: No ]
  as measured by 9-month quantitative coronary analysis

• Patients-oriented composite outcomes, including all cause death, any myocardial infarction, and any revascularization by Academic Research Consortium Proposed Standard [ Time Frame: 9 months ] [ Designated as safety issue: No ]
• 9-month angiographic restenosis rate [ Time Frame: 9 months ] [ Designated as safety issue: No ]
• 9-month stent thrombosis rate [ Time Frame: 9 months ] [ Designated as safety issue: Yes ]
• Periprocedural CK-MB elevation [ Time Frame: during the index hospitalization ] [ Designated as safety issue: Yes ]
• Procedure success rate [ Time Frame: at the end of the index procedure ] [ Designated as safety issue: No ]
• Procedure time [ Time Frame: at the end of the index procedure ] [ Designated as safety issue: No ]

The purpose of this study is to establish the optimal strategy for side branch stenting in coronary bifurcation lesion.

The purpose of this study is to evaluate the relative efficacy and safety of conservative strategy compared to aggressive strategy for side branch stenting in coronary bifurcation lesion.

• Procedure: Conservative strategy
  • Main vessel stenting was performed.
  • Side branch ballooning and kissing ballooning were done if Thrombolysis In Myocardial Infarction (TIMI) flow <3 in the side branch after main vessel stenting in non-left main bifurcation (non-LM) subgroup, and diameter stenosis (DS) >75% in LM subgroup.
  • Side branch stenting was performed if TIMI flow <3 in the Side branch after ballooning in non-LM subgroup, and DS >50% or dissection in the Side branch after ballooning in LM subgroup.
• Procedure: Aggressive strategy
  • Main vessel was performed.
  • Side branch ballooning and kissing ballooning were done if DS >75% in the side branch after main vessel stenting in non-LM subgroup, and DS >50% in LM subgroup.
  • Side branch stenting was performed if DS >50% in the side branch after ballooning in non-LM subgroup, and DS >30% or dissection in the side branch after ballooning in LM subgroup.

• Experimental: Conservative strategy
  Intervention: Procedure: Conservative strategy
• Experimental: Aggressive strategy
  Intervention: Procedure: Aggressive strategy

• Song YB, Hahn JY, Song PS, Yang JH, Choi JH, Choi SH, Lee SH, Gwon HC. Randomized comparison of conservative versus aggressive strategy for provisional side branch intervention in coronary bifurcation lesions: results from the SMART-STRATEGY (Smart Angioplasty Research Team-Optimal Strategy for Side Branch Intervention in Coronary Bifurcation Lesions) randomized trial. JACC Cardiovasc Interv. 2012 Nov;5(11):1133-40. doi: 10.1016/j.jcin.2012.07.010.
• Hahn JY, Song YB, Choi JH, Choi SH, Lee SY, Park HS, Hur SH, Lee S, Han KR, Rha SW, Cho BR, Park JS, Yoon J, Lim do S, Lee SH, Gwon HC; DATE Registry Investigators. Three-month dual antiplatelet therapy after implantation of zotarolimus-eluting stents: the DATE (Duration of Dual Antiplatelet Therapy AfterImplantation of Endeavor Stent) registry. Circ J. 2010 Oct 25;74(11):2314-21. Epub 2010 Oct 2.

Inclusion Criteria:

• Parent vessel diameter stenosis > 75%
• Parent vessel diameter stenosis 50% - 75% with angina and/or objective evidence of ischemia in the non-invasive stress test
• The reference diameter of both branches more than 2.3 mm by visual estimation

Exclusion Criteria:

• Cardiogenic shock
• ST-elevation myocardial infarction within 48 hours of symptom onset
• Left ventricular dysfunction (echocardiographic left ventricular ejection fraction < 25%)
• Graft vessels
• Patients who have to receive clopidogrel due to other conditions
• Patients who have to receive warfarin, cilostazol or other antiplatelet therapy
• Hypersensitivity to clopidogrel or aspirin
• Expectant survival less than 1 year
• Women who plan to become pregnant
• Patients with bleeding diathesis (coagulopathy, thrombocytopenia or platelet dysfunction, Gastrointestinal or genitourinary bleeding within the prior 3 months)
• Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period.