Two repetition time saturation transfer (TwiST) with spill-over correction to measure creatine kinase reaction rates in human hearts

The objective was to validate TwiST measurements of CK kinetics in healthy subjects and patients with heart failure (HF). Methods: Bloch equation simulations that included the effect of spillover irradiation on PCr were used to derive formulae for T 1 intrinsic and k f measured by both TRiST and TwiST methods. Spillover was quantified from an unsaturated PCr measurement used in the current protocol for determining PCr and ATP concentrations. Cardiac TRiST and TwiST data were acquired at 3 T from 12 healthy and 17 HF patients. Results: Simulations showed that both k f measured by TwiST and T 1 intrinsic require spill-over corrections. In human heart at 3 T, the spill-over corrected T 1 intrinsic  = 8.4 ± 1.4 s (mean ± SD) independent of study group. TwiST and TRiST k f measurements were the same, but TwiST was 9 min faster. Spill-over corrected TwiST k f was 0.33 ± 0.08 s −1...
Source: Journal of Cardiovascular Magnetic Resonance - Category: Radiology Authors: Source Type: research