title: Predictors and Outcomes of Side-Branch Occlusion in Coronary Chronic Total Occlusion Interventions.
abstract: OBJECTIVE
  We investigated whether side-branch loss during chronic total occlusion (CTO) percutaneous coronary intervention (PCI) could adversely impact clinical outcomes.
  
  
  BACKGROUND
  Side-branch occlusion during PCI has been associated with periprocedural myocardial infarction and higher incidence of major adverse cardiac event (MACE), but has received limited study in CTO-PCI.
  
  
  METHODS
  We retrospectively reviewed the medical records and coronary angiograms for 109 consecutive CTOPCI cases performed at our institution during 2012 and 2013. Post-PCI patency of ≥1 mm diameter side branches and associated clinical outcomes were assessed.
  
  
  RESULTS
  Mean age was 65 ± 8 years and 99.1% of the patients were men. The CTO target vessel was the right coronary artery (54%), circumflex (26%), and left anterior descending artery (20%). Side-branch loss occurred in 28 cases (25.7%) due to antegrade dissection/reentry (n = 9), retrograde dissection/reentry (n = 5), stenting over the branch (n = 12), and dissection during antegrade crossing attempts (n = 2). Recanalization of the occluded side branch was pursued in 8 cases (28.6%) and was successful in 4 patients. Patients with side-branch loss had higher post-PCI increase in CK-MB levels (8.4 ng/mL [interquartile range, 2.7-33.5 ng/mL] vs 1.8 ng/mL [interquartile range, 0.025-6.775 ng/mL]; P<.001) and higher 12-month incidence of all-cause death (17.3% vs 2.8%; P=.02) and cardiovascular death (7.4% vs 0.0%; P=.02).
  
  
  CONCLUSIONS
  Side-branch loss occurs in approximately 1 in 4 CTO-PCIs and is associated with higher risk for periprocedural myocardial infarction and higher mortality.
authors.forename: Phuong-Khanh J
authors.initials: PK
authors.lastname: Nguyen-Trong
authors.forename: Bavana V
authors.initials: BV
authors.lastname: Rangan
authors.forename: Aris
authors.initials: A
authors.lastname: Karatasakis
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Danek
authors.forename: Georgios E
authors.initials: GE
authors.lastname: Christakopoulos
authors.forename: Jose Roberto
authors.initials: JR
authors.lastname: Martinez-Parachini
authors.forename: Erica
authors.initials: E
authors.lastname: Resendes
authors.forename: Colby R
authors.initials: CR
authors.lastname: Ayers
authors.forename: Michael
authors.initials: M
authors.lastname: Luna
authors.forename: Shuaib
authors.initials: S
authors.lastname: Abdullah
authors.forename: Dharam J
authors.initials: DJ
authors.lastname: Kumbhani
authors.forename: Tayo
authors.initials: T
authors.lastname: Addo
authors.forename: Jerrold
authors.initials: J
authors.lastname: Grodin
authors.forename: Subhash
authors.initials: S
authors.lastname: Banerjee
authors.affiliation: VA North Texas Health Care System, The University of Texas Southwestern Medical Center at Dallas, Division of Cardiology (111A), 4500 S. Lancaster Rd, Dallas, TX 75216 USA. esbrilakis@gmail.com.
authors.forename: Emmanouil S
authors.initials: ES
authors.lastname: Brilakis
mesh_terms: D000368:Aged; D002908:Chronic Disease; D017023:Coronary Angiography / Q000379:methods; D054059:Coronary Occlusion / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000293:injuries / Q000503:physiopathology; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000175:diagnosis / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000209:etiology; D010043:Outcome and Process Assessment, Health Care; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects* / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology; D012189:Retrospective Studies; D014481:United States; D057772:Vascular System Injuries / Q000175:diagnosis / Q000209:etiology