Role of creatine phosphate as a myoprotective agent during coronary artery bypass graft in elderly patients.

Objective: To evaluate the myocardial protective effect of exogenous creatine phosphate added to a cardioplegic solution for elderly patients undergoing a coronary artery bypass graft (CABG) in China.

Methods: Twenty-four patients (age>65 years) who underwent CABG were randomly divided into a control group (n=12) and an experimental group (n=12). The concentrations of malonyldehyde and superoxide dismutase in the blood were measured before aortic clamping and at 0, 30, 60, and 120 min after the release of aortic clamping. Creatine phosphokinase (CK), creatine phosphokinase-MB (CK-MB), lactate dehydrogenase, and cardiac troponin T were measured before aortic clamping and at 2, 24, and 48 h after the release of aortic clamping. Myocardial ultrastructures were examined under an electron microscope.

Results: The concentrations of malonyldehyde in both groups increased after the release of aortic clamping (at 0, 30, 60, and 120 min), but were higher in the control group compared with the experimental group (P<0.01). The concentrations of superoxide dismutase in both groups were decreased after the release of aortic clamping and were higher in the experimental group compared with the control group (P<0.01) at 0, 30, 60, and 120 min after the release of aortic clamping. The values of CK, CK-MB, lactate dehydrogenase, and cardiac troponin T at 2, 24, and 48 h after the release of the aortic clamping were lower in the experimental group than in the control group (P<0.01). Electron microscopy showed that the mitochondria in the experimental group were histologically better than those in the control group.

Conclusion: Exogenous creatine phosphate added to the cardioplegia solution can provide energy to myocardial cells and can relieve ischemia/reperfusion-related injury in elderly patients during CABG in China.