Influence of left ventricular pressures and heart rate on myocardial high-energy phosphate metabolism.

This review describes the effects of changes in left ventricular pressures and heart rate on myocardial high-energy phosphate metabolism. When cardiac workload is substantially increased, creatine kinase flux will increase markedly, phosphocreatine will show a small but detectable decrease, and ATP will not change. In this context, heart rate is a much weaker acute metabolic stimulus than left ventricular developed pressure. However, in heart failure, chronic reduction of heart rate has beneficial effects on alterations of high-energy phosphate metabolism.