Incidence and impact of acute kidney injury in patients with acute coronary syndromes treated with coronary artery bypass grafting: Insights from the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) and Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trials

Background Acute kidney injury (AKI) is a well-recognized predictor of morbidity and mortality after percutaneous coronary intervention. However, the impact of AKI on the outcome of patients with acute coronary syndromes (ACS) in relation to coronary artery bypass grafting (CABG) has not been established. Methods Of the 17,421 patients who presented with non ST-segment elevation ACS or ST-segment elevation myocardial infarction enrolled in the ACUITY and HORIZONS-AMI trials, 1,406 (8.0%) underwent CABG as principal treatment after coronary angiography. End points were measured at 1 month and 1 year and included death, myocardial infarction, and ischemia-driven target vessel revascularization. Acute kidney injutywas defined as a rise in creatinine of >= 0.5 mg/dL, or >25%, from baseline at initial angiography. Results Acute kidney injury occurred during hospital admission in 449 (31.9%) of the 1,406 patients treated with CABG. One-month and 1-year mortality was 6.7% vs 2.2% (P < .0001) and 10.4% vs 4.3% (P < .0001) for patients with vs without AKI, respectively. Analogously, the 1-month and 1-year incidence of composite major adverse cardiac events (MACEs; death, MI, or target vessel revascularization) was 17.6% vs 12.4% (P = .003) and 22.0% vs 15.3% (P = .002) for patients with vs without AKI, respectively. After adjustment for age, sex, race, diabetes, hypertension, and baseline creatinine clearance, AKI was an independent predictor of mortality (overall and cardiac-related) and MACE at both 1 month and 1 year in patients treated with CABG. Conclusions Acute kidney injury occurred in approximately 1 of every 3 patients with ACS treated with CABG and is a powerful independent predictor of death and MACE. These data highlight the need for AKI prevention strategies in patients undergoing CABG.