title: Ostial left main coronary artery stenosis as an additional risk factor in off-pump coronary artery bypass grafting.
abstract: BACKGROUND
  Our aim was to determine whether general left main coronary artery stenosis (LMS) and ostial LMS pose additional risks after off-pump coronary artery bypass grafting (CABG) relative to non-left main coronary artery stenosis.
  
  
  METHODS
  From January 1, 2008, to December 31, 2009, 4366 patients underwent primary isolated off-pump CABG at Beijing Anzhen Hospital. Disease was retrospectively classified as non-left main disease (n = 3523), nonostial LMS (n = 765), and ostial LMS (n = 78). Groups were propensity score matched. Kaplan-Meier freedoms from major adverse cardiac and cerebrovascular events (MACCEs) were calculated.
  
  
  RESULTS
  During the first 30 postoperative days, mortality was significantly higher in the ostial LMS group (6.41%) than in non-left main disease (0.855%, χ(2) = 7.78, P = .005) and nonostial LMS (1.28%, χ(2) = 4.71, P = .03) groups. Incidence of MACCEs was significantly higher in the ostial LMS group (20.5%) than in non-left main disease (5.98%, P = .000) and nonostial LMS (9.62%, P = .002) groups. Odds ratio for early MACCEs of ostial LMS versus non-left main disease was 3.74 (95% confidence interval, 1.72-8.17). At mean follow-up 12.8 ± 7.5 months and cumulative follow-up 498.5 patient-years, difference among groups in freedom from MACCEs did not reach statistical significance (χ(2) = 2.39, P = .303).
  
  
  CONCLUSIONS
  Ostial LMS poses additional early risks of mortality and MACCEs in off-pump CABG. Off-pump CABG for ostial LMS should proceed with greater of intraoperative surveillance and lower threshold for converting to on-pump CABG.
authors.affiliation: Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China. ganhuili@hotmail.com
authors.forename: Hui-Li
authors.initials: HL
authors.lastname: Gan
authors.forename: Jian-Qun
authors.initials: JQ
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Xiao
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhao
authors.forename: Fang-jong
authors.initials: FJ
authors.lastname: Huang
authors.forename: Cheng-xiong
authors.initials: CX
authors.lastname: Gu
authors.forename: Chun-shang
authors.initials: CS
authors.lastname: Lu
authors.forename: Pi-Shan
authors.initials: PS
authors.lastname: Wang
mesh_terms: D000368:Aged; D047549:Coronary Artery Bypass, Off-Pump / Q000401:mortality*; D023921:Coronary Stenosis / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors