Refaat E. Gabr1, AbdEl-Monem M. El-Sharkawy1, Michael Schr1, 2, Robert G. Weiss, 13, Paul A. Bottomley1
1Division of MR Research, Department of Radiology, Johns Hopkins University, Baltimore, MD, United States; 2Philips Healthcare, Cleveland, OH, United States; 3Cardiology, Johns Hopkins University, Baltimore, MD, United States
The energy starvation hypothesis of heart failure (HF) suggests that energy supply may be compromised. This may limit cardiac mechanical work during peak demand. We developed a comprehensive noninvasive MRI/MRS protocol that combines 31P-MRS measures of creatine-kinase (CK) ATP energy supply with temporal MRI measurements of cardiac mechanical work. Compared to healthy subjects, we find significant reductions of 30-40% in peak cardiac work, average work and mechanical efficiency consistent with a reduction of 40% seen in creatine-kinase energy supply, suggesting that compromised CK energy supply could limit cardiac work in HF.