[Improved protection of hypertrophied myocardium in ischemia by histidine buffer cardioplegia].

Pressure overload hypertrophy has been known risk factor for open heart surgery, because of accelerated loss of high energy nucleotides, greater accumulation of H+ and lactate, and earlier onset of contracture. To test the efficacy of histidine containing cardioplegia (HB) on promotion of anaerobic glycolysis leads to improved preservation of hypertrophied heart, hypertrophied rabbit heart (aortic banding at 10 days) received HB or high potassium Krebs buffer solution (KCl) were subjected to 40 min of 37 degrees C ischemia followed by reperfusion in an isolated Langendorff mode. There was significantly higher phosphocreatine, intracellular pH and lactate production which was an indicator of anaerobic glycolysis and better recovery of cardiac function in HB group compared to KCl group. We concluded that histidine containing cardioplegia was able to promote anaerobic glycolysis to maintain high energy phosphates as well as contractile function in hypertrophied myocardium.