Abstract
The recently reported technique of retrograde continuous normothermic blood cardioplegia (RCNBC) (1) challenges currently accepted concepts of myocardial protection during heart surgery which rely on hypothermia. Theoretically, the technique seeks to create a state of aerobic arrest without any period of ischemia. This requires the continuous supply of oxygen, substrates, and potassium to the myocardium during aortic clamping.