Acute Kidney Injury Following Coronary Artery Bypass Surgery and Long-term Risk of Heart Failure
Background—Acute kidney injury (AKI) after coronary artery bypass grafting (CABG) is common and increases the risk of postoperative complications and mortality. There is little information on the association between AKI after CABG and long-term risk of incident heart failure.
Methods and Results—All patients (n = 24 018) undergoing primary, isolated CABG in Sweden between 2000 and 2008 with complete information on pre- and postoperative serum creatinine values and no prior hospitalization for heart failure were included. The postoperative increase in serum creatinine was used to define different stages of AKI: stage 1, 0.3 to 0.5 mg/dL; stage 2, 0.5 to 1 mg/dL; stage 3, >1 mg/dL. Hazard ratios (HR) with 95% confidence intervals (CI) were calculated for first hospitalization for heart failure for each stage of AKI using Cox proportional hazards regression. Twelve percent of the study population developed AKI. During a mean follow-up of 4.1 years there were 1325 (5.5%) cases of incident heart failure. Hazard ratios with 95% CI for heart failure in AKI stage 1, 2 and 3 were 1.60 (1.34 to 1.92), 1.87 (1.54 to 2.27), and 1.98 (1.53 to 2.57) respectively, after multivariable adjustment for age, sex, diabetes mellitus, estimated glomerular filtration rate, left ventricular ejection fraction, and myocardial infarction before surgery or during follow-up.
Conclusions—Acute kidney injury is associated with increased long-term risk of heart failure after CABG. Patients with AKI after CABG should be followed closely in order to detect early changes in cardiac function.
- Received August 30, 2012.
- Accepted November 29, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited