Cardioprotective conditioning with glucose and insulin prior to cardiac surgery involving ischaemic cold arrest.

The study describes cardioprotective conditioning by means of high doses of glucose together with insulin and potassium. Eighteen hours before cardiac surgery, nine patients received continuous infusion of 1000 ml of 40% glucose solution along with 112 U of insulin and 60 mmol of potassium. Before and after ischaemic cold arrest, the myocardial a--v differences of lactate, pyruvate, glucose, Na, K, Cl, Ca, P, free fatty acids and triglycerides were analysed in all patients. Blood collections were performed in parallel with ultramicroscopy of biopsy specimens from the right atrium. The results were compared with those obtained in a control group of 22 patients without cardioprotective conditioning with glucose, insulin and potassium. Neither the analysis of the myocardial a--v differences of metabolites, nor the finding on the mitochondria and myofibrils documented statistically significant differences between the control and conditioned groups. Following termination of ischaemic cold arrest, patients in the conditioned group exhibited more glycogen grains in myocardial cells than those in the control group. While 34% of patients in the control group were defibrillated after revascularization, it was not necessary in any of the conditioned patients.