147 Automated Quantitative Perfusion CMR With Simplified Dual-Bolus Contrast Protocol Simplified dual-bolus protocol The scanning protocol with simplified dual-bolus contrast administration scheme is presented in Figure 1. Stress AIF and perfusion images were acquired after at least 3 min of constant intravenous infusion of adenosine (140 μg/kg/min) while patients held their breath for as long as possible. AIF images were obtained during intravenous administration of a non-diluted pre-bolus of GBCA (DOTAREM®, Guerbet, Villepinte, France 0.5 mmol/ml) at a dose of 0.0075 mmol/kg, infusion rate 3 ml/s, flushed with 20 ml of saline. Perfusion images were obtained using a non-diluted main bolus of GBCA (DOTAREM®, Guerbet, Villepinte, France 0.5 mmol/ml) at a dose of 0.075 mmol/kg, infusion rate 3 ml/s, flushed with 20 ml of saline. GBCA and saline were administered intravenously using an MRI-compatible power injector. Notably, the pre-bolus to bolus concentration ratio was 1:10, as required for the dual-bolus approach.7 Perfusion images were acquired using a commercially available saturation recovery turbo spoiled gradientecho sequence at every heartbeat over at least 50 beats in three parallel short-axis slices at the basal, mid-ventricular and apical levels. At the beginning of each acquisition, two proton density-weighted images were obtained at all three levels for correcting surfacecoil SI inhomogeneity. Typical in-plane resolution of the myocardial perfusion images was 2.25 × 2.25 mm2, with a slice thickness of 8 mm (repetition time 2.64 ms, echo time 1.18 ms, inversion time 125 ms, flip angle 12°, matrix size 160 × 120), and a twofold acceleration using GRAPPA/T-pat. The temporal acquisition window for the perfusion images was 158 ms. Rest AIF and rest perfusion images were acquired using identical pre-bolus and bolus dosages and slice location, at least 10 min after finishing adenosine administration. In case heart rates exceeding 90 bpm, each set of perfusion images was acquired over two heartbeats. No raw data filtering was performed. 7
RkJQdWJsaXNoZXIy MTk4NDMw