Myocardial protection with leukocyte depletion in cardiac surgery

A role of neutrophils in ischemia-reperfusion injury has been focused on as one of the mediating factors of inflammatory reactions. Current studies have reported the efficacy of leukocyte-depletion in reperfusion by using leukocyte removal filter to attenuate reperfusion injury during open heart surgeries. For clinical application, we have introduced leukocyte-depleted terminal blood cardioplegia (LDTC) in adult patients and leukocyte-depleted blood cardioplegia in pediatric patients. The results of elective surgery in noncompromised LDTC did not significantly alter the results in terms of leakage of creatine kinase (CK)-MB, production of malondialdehyde from myocardium, and dopamine dose required at the weaning from cardiopulmonary bypass compared with the whole-blood reperfusion or with terminal cardioplegia alone. In contrast, the results in emergency coronary artery bypass graft (CABG) patients differed significantly between the LDTC group and the other two groups. Leukocyte-depleted reperfusion was also effective in a similar fashion for patients with severe left ventricular hypertrophy caused by chronic aortic valve disease. Leukocyte-depleted blood cardioplegia was useful in pediatric patients. Thus, leukocyte depletion may be beneficial as an adjunct to terminal blood cardioplegia or blood cardioplegia during cardiac surgery to attenuate leukocyte-mediated ischemia-reperfusion injury in patients with compromised hearts, such as those with preoperative ischemic insults, severe left ventricular hypertrophy, and in pediatric patients.