title: First report on 30-day and operative mortality in risk model of isolated coronary artery bypass grafting in Japan.
abstract: BACKGROUND
  Risk models of coronary artery bypass grafting (CABG) using a large database are useful for improving surgical quality. To obtain accurate, high-quality assessments of the surgical outcomes, each country should maintain its own database. This study was conducted to collect Japanese data and prepare a risk stratification of isolated CABG procedures using the Japan Adult Cardiovascular Surgery Database (JACVSD).
  
  
  METHODS
  We analyzed 7133 CABG-only records from 97 participating sites throughout Japan using a data entry form with 255 variables that was sent to the JACVSD office by our Web-based data collection system. The statistical model was constructed by multiple logistic regression. Model discrimination was tested using the area under the receiver operating characteristic curve (C index). Model calibration was tested by the Hosmer-Lemeshow test.
  
  
  RESULTS
  Of 7133 operations, 47.2% had diabetes mellitus, 14.0% were urgent, and 15.6% involved peripheral vascular disease. The observed 30-day and operative mortality rates were 2.02% and 2.72%, respectively. Significant variables with high odds ratios included emergency or salvage status (3.71), preoperative creatinine value exceeding 3.0 mg/dL (3.59), aortic valve stenosis (3.01), and moderate to severe chronic lung disease (2.86). Hosmer-Lemeshow test and C-index values for 30-day mortality were satisfactory at 0.96 and 0.85, respectively.
  
  
  CONCLUSIONS
  The results obtained in Japan were at least as good as those reported elsewhere. The performance of our risk model also matched those of the Society of Thoracic Surgeons National Adult Cardiac Database and the European Society Database.
authors.affiliation: Department of Cardiac Surgery, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Motomura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Miyata
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsukihara
authors.forename: Masafumi
authors.initials: M
authors.lastname: Okada
authors.forename: Shinichi
authors.initials: S
authors.lastname: Takamoto
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death; D016001:Confidence Intervals; D001026:Coronary Artery Bypass / Q000379:methods / Q000401:mortality*; D003324:Coronary Artery Disease / Q000401:mortality / Q000601:surgery*; D016208:Databases, Factual; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011183:Postoperative Complications / Q000401:mortality; D012042:Registries; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D018570:Risk Assessment; D012308:Risk Management; D017678:Sex Distribution; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors