Using magnetic resonance spectroscopy (MRS) for the first time to examine energy production biochemistry in a beating human heart, Johns Hopkins researchers have found substantial energy deficits in failing hearts.
The findings, published in the January 18 issue of the Proceedings of the National Academy of Sciences, confirm what many scientists have conjectured for years about heart failure, and suggest new treatments designed to reduce energy demand and/or augment energy transfer.
"The heart consumes more energy per gram than any other organ," notes Paul A. Bottomley, Ph.D., lead researcher and director of magnetic resonance research at the Johns Hopkins Department of Radiology. "While scientists have long known that nucleotide adenosine triphosphate (ATP) is the chemical that fuels heart contractions and that creatine kinase (CK) is the enzyme for one of the sources of ATP, we believe this is the first time someone has actually measured the flux of ATP produced by CK reaction in the beating human heart."
Specifically, Bottomley and a team of cardiologists and radiologists at Hopkins used MRS to provide direct molecular-level measurements of the CK supply in normal, stressed and failing human hearts. Other team members include Robert G. Weiss, M.D., and Gary Gerstenblith, M.D., both in the Cardiology Division of the Hopkins Department of Medicine.