GSTM1 and myocardial ischemia: The postoperative hemoglobin (Hb) level was significantly higher in patients from the IHD group than that in those from the non-IHD group (10.8 ± 1.2 vs. 10.0 ± 1.0 g/dL; p = 0.005); however, the blood transfusion volumes between the groups did not significantly differ (1330 ± 709 vs. 1324 ± 860 mL; p = 0.975).