Figure 1.

Pulse sequence diagram for cardioCEST. CEST contrast is generated via a train (N_sat) of spatially non-selective saturation pulses tuned to a specific offset frequency. The gradient echo readout module is used to acquire cine images with N cardiac phases (N_phases) following each electrocardiogram trigger. After N phases, the readout module is repeated at a constant repetition time but data is not acquired until the subsequent electrocardiogram trigger (dummy pulses). Following execution of the saturation module, the GRE readout module is executed N_ave times for one line of k-space and the results subsequently averaged prior to image reconstruction. The saturation and readout modules are repeated N_aq times to acquire all phase-encode steps. Both the offset frequency and the power of the saturation module can be adjusted to image specific molecular targets.