OBJECTIVE: Risk-adjusted operative mortality is a key quality measure for isolated coronary artery bypass grafting. Through a multicenter quality improvement initiative, we sought to improve this measure at 14 surgical programs within a large and geographically dispersed health care system.

METHODS: Observed mortality and combined mortality/morbidity rates for isolated coronary artery bypass grafting were collected from January 2014 to June 2017. Expected mortality and mortality/morbidity rates were determined using the Society of Thoracic Surgeons risk models. The observed/expected ratios during the baseline (2014) and final 12-month outcome period were compared. The quality improvement intervention was multifaceted and surgeon led, and consisted of (1) regular sharing of unblinded data, (2) standardized quality improvement processes, (3) regular system-wide quality improvement meetings, (4) annual observed/expected mortality targets, (5) identification of underperforming institutions and creation of nonpunitive quality improvement action plans, and (6) implementation of checklists to drive perioperative care standardization.

RESULTS: The observed/expected ratio of mortality was 1.19 during the baseline period and decreased to 0.59 for the outcome period (P = .004) without a change in expected mortality or case volume. The observed/expected ratio decreased for mortality/morbidity, and mortality without antecedent morbidity was almost eliminated.

CONCLUSIONS: A significant and clinically meaningful 50% reduction in the observed/expected ratio for isolated coronary artery bypass grafting mortality was observed during a multifaceted quality improvement initiative across a large multicenter health care system. Morbidity also decreased. Keys to success included surgeon leadership and engagement, frequent unblinded data sharing, development of standardized quality improvement processes, improvement and standardization of care delivery, setting of quality improvement targets, and a shared vision for improved patient outcomes.