Ischemic preconditioning in myocardial revascularization with intermittent aortic cross-clamping.

Abstract

This study tests the hypothesis that initial brief periods of ischemia can increase the protection obtained by intermittent aortic cross-clamping. In the control group (n = 18), the procedure was performed under intermittent aortic cross-clamping at 32 degrees C. Patients in the preconditioned gorup (n = 17) received a stimulus of two 3-minute periods of cross-clamping followed by 2 minutes of reperfusion prior to standard operation. CKMB, troponin 1, adenosine, and lactate were obtained from the great cardiac vein at the onset of cardiopulmonary bypass (CPB), at the end of the first anastomosis, and at the end of CPB. CKMB and troponin I were slightly higher at the end of CPB in the control group, while there was no difference between adenosine and lactate levels. [table: see text]. There was no difference between groups in terms of myocardial protection.