Does remote organ ischaemia trigger cardiac preconditioning during coronary artery surgery?

The aim of this study is to provide biochemical evidence of the occurrence of cardiac preconditioning via remote organ ischaemia on the patients under going coronary artery surgery. Eight male patients were randomly allocated into two groups. Blood samples were collected via coronary perfusion cathet er immediately before cardiopulmonary bypass (point 0), prior to declamping aorta (point 1) and 5 min after declamping the aorta (point 2) to determin e creatinine phosphokinase (CPK), CPK-MB and lactate dehydrogenase (LDH) le vels in the control group. A tourniquet wrapped around the right upper extr emity of the patient was inflated and deflated twice to perform 3 min of is chaemia separated with 2 min of reperfusion in the preconditioning group. B lood samples were withdrawn as described for the control group. Only LDH le vels at point 3 were found to be significantly higher than the control grou p's. These data implied that preconditioning appeared to protect myocardium by enhancing anaerobic glycolysis. (C) 2000 Academic Press.