Outcomes in patients undergoing coronary artery bypass graft surgery in the United States based on hospital volume, 2007 to 2011

J Thorac Cardiovasc Surg. 2016 Jun;151(6):1686-92. doi: 10.1016/j.jtcvs.2016.01.050. Epub 2016 Feb 17.

Abstract

Objective: To examine national trends in coronary artery bypass grafting (CABG) volume between 2007 and 2011, and analyze in-hospital outcomes after CABG surgery stratified according to hospital volume.

Methods: We analyzed all patients who underwent isolated CABG surgery between 2007 and 2011 in the National Inpatient Sample database. Trends in procedure volume and rates of adverse in-hospital outcomes were examined. Multivariate propensity-score adjusted analysis was performed to compare in-hospital mortality for hospitals based on quartiles of CABG volume.

Results: The frequency of isolated CABG decreased by 25.4% from 2007 to 2011 (from 326 cases per million adults to 243 cases per million adults), with the most marked decline at higher-volume centers. Patients in the highest-volume quartile were more likely to have a history of previous CABG, previous percutaneous coronary intervention, peripheral vascular disease, hypertension, or chronic renal failure. In-hospital mortality was highest in low-volume centers. In multivariate logistic regression analysis, low hospital volume was an independent predictor of in-hospital all-cause mortality (adjusted odds ratio, 1.39; 95% confidence interval, 1.24-1.56; P < .001).

Conclusions: The rate of CABG procedures has declined, mainly at high-volume centers. Low CABG volume is associated with an increase in in-hospital mortality.

Keywords: coronary artery bypass grafting; outcomes; volume.

Publication types

  • Multicenter Study

MeSH terms

  • Aged
  • Coronary Artery Bypass / mortality*
  • Coronary Artery Disease / mortality
  • Coronary Artery Disease / surgery*
  • Female
  • Hospital Mortality / trends
  • Hospitals / statistics & numerical data*
  • Humans
  • Male
  • Middle Aged
  • Odds Ratio
  • Percutaneous Coronary Intervention / mortality*
  • Propensity Score
  • Retrospective Studies
  • Risk Assessment*
  • Survival Rate / trends
  • United States / epidemiology