GSTM1 and congestive heart failure: Congestive heart failure (CHF), diabetes mellitus (DM), use of an intra-aortic balloon pump (IABP), hemoglobin level (Hb), blood urea nitrogen (BUN), and the estimated glomerular filtration rate (GFR) were all significant predictors of CI-AKI and are all components of the Mehran risk score except blood urea nitrogen (BUN), as presented in Table 2.