title: Differential effect of side branch intervention on long-term clinical outcomes according to side branch stenosis after main vessel stenting: Results from the COBIS (Coronary Bifurcation Stenting) Registry II.
abstract: BACKGROUND
  Indication of side branch (SB) intervention after main vessel (MV) stenting is not established for coronary bifurcation lesions.
  
  
  METHODS
  We evaluated 2017 patients who were treated with 1-stent technique or MV stenting as a first strategy. Patients undergoing SB intervention after MV stenting (SB intervention group, n=929) were compared to those treated with MV stenting only (no-SB intervention group, n=1088).
  
  
  RESULTS
  During a median follow-up of 37months, cardiac death or myocardial infarction (MI) tended to occur less frequently in the SB intervention group than in the no-SB intervention group (1.8% versus 2.9%; adjusted hazard ratio [HR] 0.53; 95% confidence interval [CI] 0.25-1.11; P=0.09). There was a significant interaction between SB intervention and SB stenosis after MV stenting (P for interaction <0.01). Among 1077 patients with diameter stenosis of SB ≥50% after MV stenting, SB intervention was associated with a lower risk of cardiac death or MI (1.2% versus 4.2%; adjusted HR 0.22; 95% CI 0.09-0.52; P<0.01). However, among 940 patients with diameter stenosis of SB <50%, there was no significant difference in cardiac death or MI between the SB intervention group and the no-SB intervention group (3.5% versus 2.2%; adjusted HR 1.36; 95% CI 0.58-3.20; P=0.48).
  
  
  CONCLUSIONS
  The effect of SB intervention differed according to SB stenosis after MV stenting. SB intervention may reduce cardiac death or MI in bifurcation lesions with diameter stenosis of SB ≥50% after MV stenting.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Jang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
authors.forename: Yong Hwan
authors.initials: YH
authors.lastname: Park
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: jyhahn@skku.edu.
authors.forename: Joo-Yong
authors.initials: JY
authors.lastname: Hahn
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Young Bin
authors.initials: YB
authors.lastname: Song
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Seung-Hyuk
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
authors.forename: Woo Jung
authors.initials: WJ
authors.lastname: Chun
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
authors.forename: Ju
authors.initials: J
authors.lastname: Hyeon Oh
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Bon-Kwon
authors.initials: BK
authors.lastname: Koo
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea.
authors.forename: Seung Woon
authors.initials: SW
authors.lastname: Rha
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yangsoo
authors.initials: Y
authors.lastname: Jang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Ajou University Hospital, Suwon, Republic of Korea.
authors.forename: Seung-Jea
authors.initials: SJ
authors.lastname: Tahk
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Hyo-Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Hyeon-Cheol
authors.initials: HC
authors.lastname: Gwon
mesh_terms: D000368:Aged; D017023:Coronary Angiography / Q000639:trends; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000401:mortality / Q000601:surgery*; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000601:surgery*; D003643:Death; D054855:Drug-Eluting Stents / Q000009:adverse effects / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000209:etiology / Q000401:mortality; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000401:mortality / Q000639:trends; D012042:Registries; D013997:Time Factors; D016896:Treatment Outcome
keywords: Coronary bifurcation lesion; Percutaneous coronary intervention; Side branch; Stenosis