Mortality in Coronary Artery Bypass Grafting

Over the past 48 years, coronary artery bypass grafting (CABG) has been among the most studied procedures in all of medicine. In part, this has been because CABG is a high-volume, high-cost intervention for ischemic heart disease. But, in addition to this, CABG is associated with an easily identifiable outcome that occurs with sufficient frequency to be of substantial interest to both providers and patients, namely, procedural mortality. The initial link between CABG and mortality was from the left main coronary artery subset of the Coronary Artery Surgery Study (CASS), which interestingly only included 150 patients.1Article see p 2423The development and widespread adoption of the Society of Thoracic Surgeons National Adult Database,2 the Northern New England Consortium,3 and other regional databases such as the New York State Cardiac Surgery Reporting System (CSRS),4 Michigan Society of Thoracic Surgeons,5 and Virginia Cardiac Surgery Quality Initiative6 have provided major refinements to our understanding of the impact of coronary bypass grafting on short-term (in-hospital and/or 30-day) mortality. Over the past 20 years, the risk-adjusted (RA) mortality related to CABG has declined, through a combination of process improvement2,7,8 and regional and national system intervention.3–6 According to the Society of Thoracic Surgeons National Database 2008 risk model, the short-term RA mortality for CABG has been oscillating at ≈2% for the past 3 years.9The weight of importance of short-term RA mortality as an outcome for CABG is reflected in its use as a National Quality Forum quality metric,10 in ranking hospital performance,11 and in public reporting.12 However, closer inspection of these Society of Thoracic Surgeons data demonstrate that over the …