Ischemic tolerance of the human heart during extracorporeal circulation: clinical experience.

Our clinical experiences with ischemic tolerance of the human heart under the condition of ECC during the last 15 years allow us to state the following points: 1. The healthy human myocardium can be exposed to ischemia without danger on the basis of 15 min and a myocardial temperature of 35 degrees C. This time can be prolonged following the described value of Q10=2. 2. The previous damaged human myocardium is usually not able to cover this range. Frequently ischemic load within these limits causes functional deterioration. So, in such cases ischemic tolerance has to be applied on a distinct lower base. 3. Occasional transgressions of the described ischemic tolerance time without a fatal result do not allow us in our clinic to leave the effective principles in daily routine.