title: Trends in coronary artery bypass surgery: impact on early outcomes.
abstract: BACKGROUND
  improvements in nonsurgical revascularization have left a group of higher-risk patients presenting for operation in a later stage of coronary artery disease. We undertook this study to analyze temporal changes in demographic and clinical profiles and outcomes of cardiac surgical patients.
  
  
  METHODS
  we identified and retrieved preoperative, intraoperative, and postoperative variables for 3064 consecutive patients who underwent myocardial revascularization at the Aga Khan University Hospital between 2006 and 2011. Mortality and morbidity outcomes were compared using univariate and multivariate analyses.
  
  
  RESULTS
  mean age, prevalence of left ventricular systolic dysfunction, unstable angina, mean number of occluded vessels, and arrhythmias at presentation increased steadily over time. The prevalence of diabetes, chronic lung disease, peripheral vascular disease, prior stroke, prior myocardial infarction, and left main disease declined. Operative mortality did not change significantly (3.5% vs. 3.8%, p = 0.512). Determinants of operative mortality included older age, female sex, renal insufficiency, left ventricular systolic dysfunction, and longer bypass and crossclamp times.
  
  
  CONCLUSIONS
  coronary operations are increasingly performed in higher-risk patients with greater comorbidities. Despite this, operative mortality has not increased.
authors.affiliation: Department of Cardiothoracic Surgery, Aga Khan University Hospital, Karachi, Pakistan.
authors.forename: Muhammad Musa
authors.initials: MM
authors.lastname: Salick
authors.forename: Irfan
authors.initials: I
authors.lastname: Qadir
authors.forename: Shazia
authors.initials: S
authors.lastname: Perveen
authors.forename: Shumaila
authors.initials: S
authors.lastname: Furnaz
authors.forename: Hasanat
authors.initials: H
authors.lastname: Sharif
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000401:mortality / Q000639:trends*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006785:Hospitals, University / Q000639:trends; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010154:Pakistan / Q000453:epidemiology; D015995:Prevalence; D058996:Quality Improvement / Q000639:trends; D019984:Quality Indicators, Health Care / Q000639:trends; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: Coronary artery bypass; Pakistan; coronary disease; myocardial revascularization; treatment outcome