Quantification of human cardiac inorganic phosphate content in vivo by 31P-MRSI at 7T

Synopsis: Determination of human cardiac Pi using 31P-MRS is challenging as the resonance frequency of Pi is concealed by a close resonating 2,3-DPG signal originating from blood. Long TR acquisition using adiabatic excitation at 7T can compensate for the rapid blood signal replacement in partially-saturated short TR scans. In order to quantify Pi concentration in vivo, knowledge about longitudinal relaxation of Pi is still required. We have measured the T1 of Pi in 4 healthy volunteers at 7T using dual-TR method and used this value to quantify cardiac Pi concentration in 8 healthy volunteers.We acknowledge financial support from a Sir Henry Dale Fellowship awarded by the Wellcome Trust and the Royal Society (098436/Z/12/Z), and from Slovak Grant Agencies VEGA (2/0001/17) and APVV (15-0029)